[Quality control for standard specimen processing after gastric cancer surgery]

Gastric cancer is one of the most common malignant tumors in China. Currently, the surgery-based procedure is still the most acceptable strategy for treating gastric cancer. As an important part of standardized management, appropriate specimen processing following surgery is receiving more and more attention across the world. With the release of guidelines and consensus on the specimens processing after gastric cancer surgery, several centers in China have started to follow this standard procedure. However, due to differences in understanding the consensus and the degree of surgery practice, the results are variable. This paper will focus on reviewing every aspect of the processing procedure, with the hope that the concept and skill involved can be popularized in clinical operations. Hopefully this will help promote the development of high-quality gastric cancer surgery in China.

[Clinical analysis of 11 cases multisystem inflammatory syndrome associated with SARS-CoV-2 Omicron variant infection in children]

Objective: To explore the clinical characteristics, diagnosis, treatment, and follow-up of multisystem inflammatory syndrome in children (MIS-C) related to SARS-CoV-2 Omicron variant infection. Methods: A retrospective analysis was conducted on clinical data of 11 children with MIS-C, who were admitted to the Department of Pediatrics of Peking University First Hospital from December 2022 to January 2023. Clinical characteristics, treatment, and follow-up of MIS-C were summarized in this study. Results: The 11 cases contained 7 boys and 4 girls, with an age of 4.4 (2.0, 5.5) years on admission. All the patients had fever, with a duration of 7(5, 9) days. Other clinical manifestations included rash in 7 cases, conjunctival hyperemia in 5 cases, red lips and raspberry tongue in 3 cases, lymphadenopathy in 3 cases, and swollen fingers and toes in 2 cases. There were 8 cases of digestive symptoms, 8 cases of respiratory symptoms, and 3 cases of nervous system symptoms. Eight patients had multi-system injuries, and one of them had shock presentation. All 11 patients were infected with SARS-CoV-2 Omicron BF.7 variant. The laboratory examination results showed that all cases had elevated inflammatory indicators, abnormal coagulation function and myocardial damage. Six patients had elevated white blood cell counts, 5 cases had liver function abnormalities, 3 cases had kidney function abnormalities, and 8 cases had coronary artery involvement. All 11 patients received anti-infection treatment, of which 3 cases received only 2 g/kg intravenous immunoglobulin (IVIG), while the remaining 8 cases received a combination of IVIG and 2 mg/(kg·d) methylprednisolone. Among the 8 cases with coronary artery disease, 6 cases received low molecular weight heparin anticoagulation therapy. All patients were followed up in 2 weeks after being discharged, and their inflammatory markers had returned to normal by that time. The 8 cases with coronary artery disease and 3 cases with pneumonia showed significant improvement or back to normal at the 4-week follow-up. All patients had no new complications or comorbidities during follow-up of more than 3 months. Conclusions: MIS-C may present with Kawasaki disease-like symptoms, with or without gastrointestinal, neurological, or respiratory symptoms. Elevated inflammatory markers, abnormal coagulation function, and cardiac injury contribute to the diagnosis of MIS-C. IVIG and methylprednisolone were the primary treatments for MIS-C, and a favorable short-term prognosis was observed during a follow-up period of more than 3 months.

Transcriptomic and clinical heterogeneity of metastatic disease timing within metastatic castration-sensitive prostate cancer

BACKGROUND

Metastatic castration-sensitive prostate cancer (mCSPC) is commonly classified into high- and low-volume subgroups which have demonstrated differential biology, prognosis, and response to therapy. Timing of metastasis has similarly demonstrated differences in clinical outcomes; however, less is known about any underlying biologic differences between these disease states. Herein, we aim to compare transcriptomic differences between synchronous and metachronous mCSPC and identify any differential responses to therapy.

PATIENTS AND METHODS

We performed an international multi-institutional retrospective review of men with mCSPC who completed RNA expression profiling evaluation of their primary tumor. Patients were stratified according to disease timing (synchronous versus metachronous). The primary endpoint was to identify differences in transcriptomic profiles between disease timing. The median transcriptomic scores between groups were compared with the Mann-Whitney U test. Secondary analyses included determining clinical and transcriptomic variables associated with overall survival (OS) from the time of metastasis. Survival analysis was carried out with the Kaplan-Meier method and multivariable Cox regression.

RESULTS

A total of 252 patients were included with a median follow-up of 39.6 months. Patients with synchronous disease experienced worse 5-year OS (39% versus 79%; P < 0.01) and demonstrated lower median androgen receptor (AR) activity (11.78 versus 12.64; P < 0.01) and hallmark androgen response (HAR; 3.15 versus 3.32; P < 0.01). Multivariable Cox regression identified only high-volume disease [hazard ratio (HR) = 4.97, 95% confidence interval (CI) 2.71-9.10; P < 0.01] and HAR score (HR = 0.51, 95% CI 0.28-0.88; P = 0.02) significantly associated with OS. Finally, patients with synchronous (HR = 0.47, 95% CI 0.30-0.72; P < 0.01) but not metachronous (HR = 1.37, 95% CI 0.50-3.92; P = 0.56) disease were found to have better OS with AR and non-AR combination therapy as compared with monotherapy (P value for interaction = 0.05).

CONCLUSIONS

We have demonstrated a potential biologic difference between metastatic timing of mCSPC. Specifically, for patients with low-volume disease, those with metachronous low-volume disease have a more hormone-dependent transcriptional profile and exhibit a better prognosis than synchronous low-volume disease.

[Clinical and genetic characteristics of 9 rare cases with coexistence of dual genetic diagnoses]

Objective: To analyze the clinical and genetic characteristics of pediatric patients with dual genetic diagnoses (DGD). Methods: Clinical and genetic data of pediatric patients with DGD from January 2021 to February 2022 in Peking University First Hospital were collected and analyzed retrospectively. Results: Among the 9 children, 6 were boys and 3 were girls. The age of last visit or follow-up was 5.0 (2.7,6.8) years. The main clinical manifestations included motor retardation, mental retardation, multiple malformations, and skeletal deformity. Cases 1-4 were all all boys, showed myopathic gait, poor running and jumping, and significantly increased level of serum creatine kinase. Disease-causing variations in Duchenne muscular dystrophy (DMD) gene were confirmed by genetic testing. The 4 children were diagnosed with DMD or Becker muscular dystrophy combined with a second genetic disease, including hypertrophic osteoarthropathy, spinal muscular atrophy, fragile X syndrome, and cerebral cavernous malformations type 3, respectively. Cases 5-9 were clinically and genetically diagnosed as COL9A1 gene-related multiple epiphyseal dysplasia type 6 combined with NF1 gene-related neurofibromatosis type 1, COL6A3 gene-related Bethlem myopathy with WNT1 gene-related osteogenesis imperfecta type XV, Turner syndrome (45, X0/46, XX chimera) with TH gene-related Segawa syndrome, Chromosome 22q11.2 microduplication syndrome with DYNC1H1 gene-related autosomal dominant lower extremity-predominant spinal muscular atrophy-1, and ANKRD11 gene-related KBG syndrome combined with IRF2BPL gene-related neurodevelopmental disorder with regression, abnormal movement, language loss and epilepsy. DMD was the most common, and there were 6 autosomal dominant diseases caused by de novo heterozygous pathogenic variations. Conclusions: Pediatric patients with coexistence of double genetic diagnoses show complex phenotypes. When the clinical manifestations and progression are not fully consistent with the diagnosed rare genetic disease, a second rare genetic disease should be considered, and autosomal dominant diseases caused by de novo heterozygous pathogenic variation should be paid attention to. Trio-based whole-exome sequencing combining a variety of molecular genetic tests would be helpful for precise diagnosis.

[Current status and progress in the standardized surgical management of specimens after radical gastric cancer surgery]

Standardized surgical management of postoperative specimens of gastric cancer is an important part of the standardized diagnosis and treatment of gastric cancer. It can reflect the accurate number and detailed distribution of lymph nodes in the specimen and lay the foundation for accurate and standardized pathological reports after surgery. Meanwhile, it can evaluate the scope of intraoperative lymph node dissection, the safety of cutting edge, and the standardization of surgery (principle of en-bloc dissection), which is an important means of surgical quality control. It also provides accurate research samples for further research and is an important way for young surgeons to train their clinical skills. The surgical management of postoperative specimens for gastric cancer needs to be standardized, including specimen processing personnel, processing flow, resection margin examination, lymph node sorting, measurement after specimen dissection, storage of biological specimens, documentation of recorded data, etc. The promotion of standardized surgical management of specimens after radical gastrectomy can promote the homogenization of gastric cancer surgical diagnosis and treatment in medical institutions and further promote the high-quality development of gastric cancer surgery in China.

[Establishment of Beijing National Medical School Faculty of Dentistry]

The Beijing National Medical School Faculty of Dentistry was established in 1943. This article reviewed the files preserved in Beijing Municipal Archices and presented the early background of the establishment including the approval process, formulation of teaching plans and design of the curriculums. These historical records provide us with thought-provoking insights into the evolution of the stomatological discipline and subsequent development of various sub-disciplines, as well as the educational ideals embedded.

Prevalence of SARS-CoV-2 Antibody in 2,935 Healthcare Workers at 6 Major Hospitals, Daegu, Korea

BACKGROUND

In Korea, the first community outbreak of coronavirus disease 2019 (COVID-19) occurred in Daegu on February 18, 2020. This study was performed to investigate the prevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antibodies in healthcare workers (HCWs) at 6 major hospitals in Daegu.

METHODS

Blood specimens of 2,935 HCWs at 6 major hospitals in Daegu from January 2021 to February 2021 were collected. Every specimen was tested for antibody against SARS-CoV-2 using both Elecsys Anti-SARS-CoV-2 electrochemiluminescence immunoassay (Roche Diagnostics, Rotkreuz, Switzerland) and R-FIND COVID-19 IgG/M/A enzyme-linked immunosorbent assay kit (SG medical Inc., Seoul, Korea) as screening tests. If 1 or more of these screening test results was positive, 2 additional antibody tests were performed using Abbott Anti-SARS-CoV-2 IgG assay (Abbott, Abbott Park, IL, USA) and cPass SARS-CoV-2 Neutralization Antibody Detection Kit (GenScript USA Inc., Piscataway, NJ, USA). If 2 or more of the total 4 test results were positive, it was determined as positive for the antibody against SARS-CoV-2.

RESULTS

According to the criteria of SARS-CoV-2 antibody positivity determination, 12 subjects were determined as positive. The overall positive rate of the SARS-CoV-2 antibody was 0.41% (12/2,935). Of the 12 subjects determined as positive, 7 were diagnosed with COVID-19, and the remaining 5 were nondiagnosed cases of COVID-19.

CONCLUSION

In early 2021, the overall seroprevalence of SARS-CoV-2 antibody among HCW located in Daegu was 0.41%, and 0.17% excluding COVID-19 confirmed subjects. These results were not particularly high compared with the general public and were much lower than HCWs in other countries.

[Application of modified Kamikawa anastomosis in digestive tract reconstruction after proximal gastrectomy]

Objective: Traditional Kamikawa anastomosis in digestive tract reconstruction after proximal gastrectomy can greatly decrease the anastomosis-related complications and reduce the incidence of reflux esophagitis, but its complexity limits the wide application. To decrease the complexity of Kamikawa anastomosis, the surgical team of Changzhi People's Hospital of Shanxi Changzhi Medical College improved this technique by using novel notion and reduced surgical procedures. This study aims to evaluate the efficacy and safety of modified Kamikawa anastomosis in digestive tract reconstruction after proximal gastrectomy. Methods: A descriptive cohort study was carried out. Case enrollment criteria: (1) upper gastric carcinoma or esophagogastric junction carcinoma without distant metastasis was confirmed by preoperative gastroscopic biopsy and imaging examination; (2) tumor diameter was less than 4 cm; (3) preoperative clinical staging was cT1-3N1M0. Exclusion criteria: (1) patients received preoperative neoadjuvant chemotherapy; (2) patients had severe heart or lung disease, or poor nutritional status so that they could not tolerate surgery. Clinical data of 25 patients with upper gastric carcinoma or esophagogastric junction carcinoma who underwent modified Kamikawa anastomosis in digestive tract reconstruction in Heji Hospital (8 cases) and Changzhi People's Hospital (17 cases) from April 2019 to December 2020 were retrospectively collected. Of 25 patients, 21 were male and 4 were female, with mean age of 63.0 (49 to 78) years; 3 underwent open surgery and 22 underwent laparoscopic surgery. The modified Kamikawa anastomosis was as follows: (1) the novel notion of total mesangial resection of the esophagogastric junction was applied to facilitate the thorough removal of lymph nodes and facilitate hand-sewn anastomosis and embedding; (2) the diameter of the anastomotic stoma was selected according to the diameter of the esophageal stump, between 2.5 and 3.5 cm, to reduce the occurrence of anastomotic stenosis; (3) an ultrasonic scalpel was used to incise the esophageal stump, which could not only prevent bleeding of the esophageal stump, but also closely seal the esophageal mucosa, muscle layer and serosa to prevent esophageal mucosa retraction; (4) barbed suture was used to suture the remnant stomach fundus and esophagus to fix the stomach fundus in order to reduce the cumbersome and difficult intermittent sutures in a small space; (5) two barbed sutures were used to continuously suture the front and back walls of the anastomosis and complete the suture and fixation of the muscle flap. Relevant indicators of surgical safety, postoperative complications (using the Clavien-Dindo classification), esophageal reflux symptoms and the occurrence of esophagitis (using Los Angeles classification) were analyzed. The gastroesophageal reflux disease (GERD) score, gastroscopy, multi-position digestive tract radiography during postoperative follow-up were used to evaluate the residual gastric motility and anti-reflux efficacy. Results: Modified Kamikawa anastomosis in digestive tract reconstruction after proximal gastrectomy was successfully performed in 25 patients. The surgical time was (5.8±1.8) hours, the intraoperative blood loss was (89.2±11.8) ml, and the average hospital stay was (13.8±2.9) days. Three cases (12.0%) developed postoperative anastomotic stenosis as Clavien-Dindo grade III and were healed after endoscopic dilation treatment. Postoperative upper gastrointestinal radiography showed 1 case (4.0%) with reflux symptoms as Clavien-Dindo grade I. Gastroscopy showed no signs of reflux esophagitis, and its Los Angeles classification was A grade. No anastomotic bleeding, local infection and death were found in all the patients. At postoperative 6-month of follow-up, GERD score showed no significant difference compared to pre-operation (2.7±0.6 vs. 2.4±1.0, t=-1.495, P=0.148). Conclusion: Modified Kamikawa anastomosis in digestive tract reconstruction after proximal gastrectomy is safe and feasible with good anti-reflux efficacy.

[Current status of research on standardized management of specimens after radical gastrectomy for gastric cancer]

The quality control and standardization of procedures in radical gastrectomy for gastric cancer, especially the standardized processing of specimens after radical gastrectomy for gastric cancer, is very important. It is not only the basis of accurate pathological staging, but also the evidence of surgical quality and the original data of clinical research, which plays a pivotal role. The examination and classification of lymph nodes, specimens processing records, and data uploading and archiving after radical gastrectomy for gastric cancer are indispensable. It is necessary for surgeons to participate in the processing of surgical specimens. This article will combine the current research status and progress at home and abroad to review the standardized processing of specimens after radical gastrectomy for gastric cancer.

[A preliminary study on molecular target identification of drugs in individualized treatment of malignant solid tumors in children]

Objective: To explore the role of drug-related molecular target identification in the individualized treatment of malignant solid tumors in children. Methods: The clinical data of 40 patients diagnosed with malignant solid tumors from Beijing Tongren Hospital, Capital Medical University, between June 2017 and March 2019 were retrospectively analyzed. Immunohistochemistry, polymerase chain reaction and sequencing methods were used to determine the expression levels and mutations of tumor drug molecular targets, and to compare the efficiency as well as the incidence of toxic side effects of chemotherapy using anti-tumor drugs with various molecular targets. Results: A total of 4 tumor drug-related targets were identified in 40 tumor tissue samples, namely DNA topoisomerase-ⅡA (TOPOⅡA), β(3)-tubulin (Tubulinβ(3)), DNA topoisomerase-Ⅰ(TOPOⅠ) and dihydrofolate reductase gene polymorphisms [DHFR (C829T)]. The effective rates of platinum-based agents, methotrexate, irinotecan, vinblastine and anthracycline for malignant solid tumors in children were 90.0% (36/40), 85.0% (34/40), 70.0% (28/40), 67.5% (27/40), 62.5% (25/40), respectively. The effective rates of chemotherapy with irinotecan, methotrexate, and vinblastine in mesenchymal tumors were 68.9% (20/29), 62.1% (18/29), 68.9% (20/29), respectively, which were considerably higher than 18.2% (2/11), 36.4% (4/11) and 36.4% (4/11) in non-mesenchymal tumors, with significant differences (χ(2)=5.487, 15.345, 17.278, all P<0.05). The effective rate of chemotherapy of platinum-based drugs for non-mesenchymal tumors was 72.3% (8/11), which was significantly higher than 58.6% (17/29) in mesenchymal tumors, and the difference was statistically significant (χ(2)=11.231, P<0.05). The intensity of toxic side effects in order from high to low was anthracycline > platinum > methotrexate > vinblastine > irinotecan. Conclusion: Tumor drug-related molecular targets and the sensitivity of tumors of different origins to the same anti-tumor drug as well as side effects are predicted, which provides a theoretical and clinical basis for individualized treatment of malignant tumors in children.

The impact of infection control cost reimbursement policy on central line-associated bloodstream infections

BACKGROUND

In September 2016, the Korean National Health Insurance Service began reimbursing infection control (IC) costs on the condition that a certain number of doctors and full-time nurses for IC be allocated to supported hospitals. We analyzed the impact of the IC cost reimbursement policy on central line-associated bloodstream infections (CLABSIs).

METHODS

A before-and-after study that analyzed the CLABSI rate trends between preintervention (January 2016 to February 2017) and intervention (March to December 2017) periods using autoregression time series analysis was performed in intensive care units (ICUs) at a 750-bed, secondary care hospital in Daegu, Republic of Korea. The enhanced IC team visited ICUs daily, monitored the implementation of CLABSI prevention bundles, and educated all personnel involved in catheter insertion and maintenance from March 2017.

RESULTS

Autoregressive analysis revealed that the CLABSI rates per month in the preintervention and intervention periods were -0.256 (95% confidence interval, -0.613 to 0.101; P = .15) and -0.602 (95% confidence interval, -0.972 to -0.232; P = .008), respectively. The rates of compliance with maximal barrier precautions significantly improved from the preintervention (36.2%) to the intervention (77.9%) period (χ² test, P < .001).

CONCLUSIONS

The IC cost reimbursement policy accelerated the decline in CLABSI rates significantly in monitored ICUs. A nationwide study to evaluate the effectiveness of the IC cost reimbursement policy for various health care-associated infections is warranted.

MCR1 and KPC2 Co-producing Klebsiella pneumoniae Bacteremia: First Case in Korea

Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-KP) has been disseminating nationwide due to clonal spread and is taking a serious action at the national level in Korea. The mobilized colistin resistance (MCR1) gene confers plasmid-mediated resistance to colistin and is known to be capable of horizontal transfer between different strains of a bacterial species. We have experienced a fatal case of the patient who developed MCR1-possessing, ST307/Tn4401a[blaKPC2] K. pneumonia bacteremia in the community of non-capital region after being diagnosed as pancreatic cancer with multiple liver metastases and treated in the capital region. The ST307/Tn4401a[blaKPC2] K. pneumonia was the most commonly disseminated clone in Korea. Our strain is the first MCR1 and KPC2 co-producing K. pneumonia in Korea and our case is the critical example that the multi-drug resistant clone can cause inter-regional spread and the community-onset fatal infections. Fortunately, our patient was admitted to the intensive care unit on the day of visit, and the contact precaution was well maintained throughout and KPC-KP was not spread to other patients. The high risk patients for KPC-KP need to be screened actively, detected rapidly and preemptively isolated to prevent outbreak of KPC-KP. Inter-facility communications are essential and the nationwide epidemiologic data of KPC-KP should be analyzed and reported regularly to prevent spread of KPC-KP. The prompt identification of species and antimicrobial susceptibilities for successful treatment against KPC-KP should be emphasized as well.

[Differences in small airway lesions in patients with different types of idiopathic interstitial pneumonia]

Objective: To investigate the differences in small airway lesions in patients with different types of idiopathic interstitial pneumonia (IIPs). Methods: A total of 46 patients with IIPs confirmed by video assisted thoracoscopic or open lung biopsy, hospitalized in the Respiratory and Critical Care Medicine of Beijing Chao-Yang Hospital, from Dec. 1998 through Nov. 2007 were studied, including 19 patients with idiopathic pulmonary fibrosis (IPF group), 14 with nonspecific interstitial pneumonia (NSIP group), and 13 cryptogenic organizing pneumonia (COP group). Pulmonary function and high resolution CT (HRCT) of the patients were examined before lung biopsy, and lung biopsy tissue were stained with hematoxylin-eosin. The abnormality of small airways in pathology, pulmonary function and HRCT were compared among these patients with IIPs. Results: Small airway inflammatory cell infiltration score (53.8±17.7) was significantly higher in the COP group than in the IPF group (38.8±9.7) (P<0.01). The fibrous tissue proliferation score in small airways (42.9±12.1) in the IPF group was significantly higher than that in the NSIP group (31.4±10.5) and the COP group (26.7±16.3) (both P<0.05). In the IPF group, NSIP group and COP group, the small airway function index was significantly reduced, and the maximum expiratory flow rate (V(25%), V(50%)) at 25% and 50% of the lung capacity was<80% predicted, the incidences of small airway dysfunction in the three groups were 63.2%, 69.2%, and 63.6%, respectively. There was no significant difference among the groups (P>0.05). Small airway inflammatory cell infiltration was negatively correlated with V(50%) of small airway function (r=-0.305, P=0.049). The bronchodilation rate in the HRCT of the IPF group (100%) was significantly higher than that of the NSIP group (50.0%) and the COP group (53.8%) (both P<0.01). Conclusion: The patients with IPF, NSIP and COP have abnormal pathologic, physiological and imaging changes of small airways, moreover have different characteristics.

[Analysis of edge morphology of partial veneers made by different processing techniques and materials]

OBJECTIVE

To compare the edge morphology of partial veneers made of different materials by slurry molding, heat-pressed and computer aided design/computer aided manufacturing (CAD/CAM) techniques.

METHODS

Thirty premolars with smooth surface and intact enamel were selected and randomly divided into five groups, 6 specimens for each group. Group A were made from feldspathic porcelain (Noritake®) by slurry molding, while Group B were made from lithium disilicate glass ceramic (IPS E.max® Press) by heat-pressed. Group C/D/E were respectively made from feldspar porcelain block (VITA Mark II®), zirconia-reinforced glass ceramic (VITA Suprinity®) and hybrid ceramic with a ceramic-polymer network (VITA Enamic®) by CAD/CAM techniques. All the partial veneers luted with light-cured composite resin. Then the partial veneers were trimmed and polished to achieve the smooth finishing margin, clinical polishing sets were used according to the product descriptions. Scanning electron microscope (SEM) was used to observe the edge morphology of prostheses and the exposure of resin cements.

RESULTS

The smooth surface and knife-like edge of the partial veneers could be obtained after bonding, trimming and polishing. The edges of Group A were slightly rough and the width of the exposed adhesive was (106.00±9.17) μm. In Group B, the edges were smoother than Group A, and the exposed wide adhesive strip was visible, which was (138.33±20.59) μm. In Group E, the edges were smooth too, and the width of exposed adhesive strip was (186.00±5.66) μm. The edges of Group C and Group D were rough and uneven, and the adhesive was rarely exposed, they were (50.67±7.51) μm and (65.67±17.90) μm. There were all significant differences between two groups, except Group C and Group D.

CONCLUSION

After trimming and polishing in accordance with clinical procedures, the expected knife-like edge can be obtained in all groups. The width of the exposed resin adhesive of each group is different, the order: Mark II/Suprinity < Noritake < E.max Press < Enamic. The edge morphology of partial veneers in different processing technic and materials are different.

Length of hospital stay after hip fracture surgery and 1-year mortality

There is ongoing effort to discharge patients early after hip fracture surgery to reduce the medical and economic burden. We tried to find whether there is any related side effect, and discovered that early discharge, especially before 10 days after surgery, is associated with higher mortality.

INTRODUCTION

The aim of this study was to analyze the association between the length of hospital stay after hip fracture and 1-year mortality in older adults aged ≥ 65 years old.

METHODS

We conducted a retrospective cohort study using the Korean National Health Insurance Service data to identify patients who were discharged after hip fracture surgery from 2007 to 2009 among 487,460 older adults of age ≥ 65 years. The lengths of stay involving hip fracture surgery were categorized at 10-day interval, and analyzed in relation to 1-year mortality from the date of hospital discharge.

RESULTS

A total of 4213 patients were discharged after hip fracture surgery, of whom 604 (14.3%) died within 1 year of discharge. The average length of stay was 30.7 days (standard deviation 24.5 days). The 1-year mortality was the highest for the length of stay ≤ 10 days group at 21.7%, followed by 15.2%, 14.3%, 13.3%, and 12.4% for > 40, 21-30, 31-40, and 11-20 days groups, respectively (p value 0.05). On Cox proportional hazard regression, the adjusted hazard ratio for length of stay ≤ 10 days group was 1.56 (95% confidence interval 1.14-2.12) against the reference group (11-20 days), while other groups did not show statistical significance. Higher risk of death was associated with increasing age, male gender, Charlson comorbidity index ≥3, subtrochanteric fracture, and discharge to tertiary care hospitals and long-term care hospitals.

CONCLUSION

Older adults discharged within 10 days of hospital admission for hip fracture surgery have higher 1-year mortality after discharge.

[Metformin protects against bleomycin-induced pulmonary fibrosis in mice]

Objective: To explore the effect of metformin on murine model of bleomycin (BLM)-induced lung injury and fibrosis. Methods: A total of 30 mice were divided into 3 groups: control, BLM, and BLM with metformin, in accordance with the random number table and each group had 10 mice. To induce the pulmonary fibrosis model, a concentration of 2 mg/ml bleomycin was intratracheally administered in the BLM group and BLM with metformin group with a volume of 1.75 μl/g, while the control group accepted saline with the same volume. Metformin (200 mg/kg) was given to the mice orally once a day from the day before intratracheal instillation of bleomycin to day 14. The daily survival condition of mice was recorded during 14 days. At day 14, HE-staining was used to assess the severity of fibrosis according to the method proposed by Ashcroft. Total lung collagen content was determined by hydroxyproline assay and Masson's trichrome staining. To examine the expression of fibronectin we used the method of immunohistochemistry staining. The changes of Transforming Growth Factor beta 1 (TGF-β(1)) in plasm, bronchoalveolar lavage fluid (BALF) and lung were measured by ELISA. Results: The survival rates of control group, BLM group and BLM with metformin group at day 14 were 10/10, 4/10 and 7/10 respectively. According to the method proposed by Ashcroft the score of metformin treated mice was significantly lower than that of the bleomycin model mice[(3.82±0.58) vs (7.79±0.06), (P<0.05)]. The hydroxyproline level in lung tissue were markedly attenuated in metformin treated mice compared with bleomycin model mice [(0.40±0.05) vs (0.73±0.10) μg/mg, (P<0.05)]. The level of TGF-β(1) in plasma, BALF and lung tissue were also decreased in mice treated with metformin compared with bleomycin model mice [(2.32±0.68) vs (4.59±0.45) ng/ml, (0.81±0.09) vs (1.40±0.06) ng/ml, (17.12±0.83) vs (21.25±0.69) ng/mg, all P<0.05]. Conclusion: Metformin can reduce the severity of pulmonary fibrosis in mice induced by bleomycin.

End-of-radiation PSA as a novel prognostic factor in patients undergoing definitive radiation and androgen deprivation therapy for prostate cancer

Background

In men undergoing definitive radiation for prostate cancer, it is unclear whether early biochemical response can provide additional prognostic value beyond pre-treatment risk stratification.

Methods

Prostate cancer patients consecutively treated with definitive radiation at our institution by a single provider from 1993–2006 and who had an EOR PSA (n=688, median follow-up 11.2 years). We analyzed the association of an end-of-radiation (EOR) prostate-specific antigen (PSA) level, obtained during the last week of radiation, with survival outcomes. Multivariable-adjusted cox proportional hazards models were constructed to assess associations between a detectable EOR PSA (defined as ≥0.1 ng ml⁻¹) and biochemical failure-free survival (BFFS), metastasis-free survival (MFS), prostate cancer-specific survival (PCSS), and overall survival (OS). Kaplan-Meier survival curves were constructed, with stratification by EOR PSA.

Results

At the end of radiation, the PSA level was undetectable in 30% of patients. Men with a detectable EOR PSA experienced inferior 10-year BFFS (49.7% vs. 64.4%, p<0.001), 10-year MFS (84.8% vs. 92.0%, p=0.003), 10-year PCSS (94.3% vs. 98.2%, p=0.007), and 10-year OS (75.8% vs. 82.5%, p=0.01), as compared to men with an undetectable EOR PSA. Among NCCN intermediate- and high-risk men who were treated with definitive radiation and androgen deprivation therapy (ADT), a detectable EOR PSA was more strongly associated with PCSS than initial NCCN risk level (EOR PSA: HR 5.89, 95% CI 2.37–14.65, p<0.001; NCCN risk level: HR 2.01, 95% CI 0.74–5.42, p=0.168). Main study limitations are retrospective study design and associated biases.

Conclusions

EOR PSA was significantly associated with survival endpoints in men who received treated with definitive radiation and ADT. Whether the EOR PSA can be used to modulate treatment intensity merits further investigation.

Unscreened older men diagnosed with prostate cancer are at increased risk of aggressive disease

BACKGROUND

To evaluate the relationship between PSA testing history and high-risk disease among older men diagnosed with prostate cancer.

METHODS

Records from 1993 to 2014 were reviewed for men who underwent radiotherapy for prostate cancer at age 75 years or older. Patients were classified into one of four groups based on PSA-testing history: (1) no PSA testing; (2) incomplete/ineffective PSA testing; (3) PSA testing; or (4) cannot be determined. Outcomes of interest were National Comprehensive Cancer Network (NCCN) risk group (that is, low, intermediate or high risk) and biopsy grade at diagnosis. Multivariable logistic regression was used to determine the association between PSA testing history and high-risk cancer.

RESULTS

PSA-testing history was available in 274 (94.5%) of 290 subjects meeting study criteria. In total, 148 men (54.0%) underwent PSA testing with follow-up biopsy, 72 (26.3%) underwent PSA testing without appropriate follow-up, and 54 men (19.7%) did not undergo PSA testing. Patients who underwent PSA testing were significantly less likely to be diagnosed with NCCN high-risk cancer (23.0% vs 51.6%, P<0.001). On multivariable analysis, men with no/incomplete PSA testing had more than three-fold increased odds of high-risk disease at diagnosis (odds ratio 3.39, 95% confidence interval 1.96-5.87, P<0.001) as compared to the tested population.

CONCLUSIONS

Older men who underwent no PSA testing or incomplete testing were significantly more likely to be diagnosed with high-risk prostate cancer than those who were previously screened. It is reasonable to consider screening in healthy older men likely to benefit from early detection and treatment.

Current status of cord blood banking during first two years of 'National Government-Assigned Public Cord Blood Banks Operation' in Korea

Cord blood (CB) has become a viable stem cell source for hematopoietic stem cell transplantation (HSCT), and public cord blood banks (CBBs) have been established to manage donated cord blood units (CBUs) for unrelated HSCT. As the potential uses for CB continue to grow, there is a global tendency to encourage public CBBs. The aim of this study was to investigate the current status of public CBBs that were designated and supported by the Korean national government. We analyzed 6,168 CBUs preserved at the 3 Government-Assigned Public CBBs during their first two years of operation (2012-2013) and the standard operating procedures for CB processing at each CBB. CBU inventories at ALLCORD, Catholic HSC Bank and Fatima Public CBB were 4,022, 1,207 and 939 units, respectively. Total nucleated cell (TNC) counts per unit were 11.0 × 10(8) at ALLCORD, 10.7 × 10(8) at Fatima and 9.8 × 10(8) at Catholic, and all far exceeded the requirement for cryopreservation under the law (7.0 × 10(8)). CD34(+) cell counts and % were as follows: 3.5 × 10(6) (0.31 %) in ALLCORD, 2.2 × 10(6) (0.20 %) in Fatima and 2.2 × 10(6) (0.22 %) in Catholic. All the three banks observed the 'CB Act' in dealing with CBUs, including collection, processing, laboratory tests and cryopreservation. Government supported and strictly law-abiding public CBBs in Korea have considerable CBU inventories of high quality in terms of efficacy and safety. Legislation and accompanying government-support will be helpful for establishing CB standardization, vitalizing CBT and improving clinical outcomes.

Third-generation cephalosporin resistance of community-onset Escherichia coli and Klebsiella pneumoniae bacteremia in a secondary hospital

BACKGROUND/AIMS

To enable appropriate antimicrobial treatment for community-onset infections in emergency departments (EDs), data are needed on the resistance profiles of Escherichia coli and Klebsiella pneumoniae, which are the main pathogens of community-onset bacteremia.

METHODS

Records were reviewed of 734 patients with E. coli and K. pneumoniae bacteremia who visited the Daegu Fatima Hospital ED, Daegu, Korea between 2003 and 2009. We investigated the demographic data, clinical findings, and antimicrobial susceptibility patterns of the organisms.

RESULTS

Of 1,208 cases of community-onset bacteremia, 62.8% were caused by E. coli or K. pneumoniae in an ED of a secondary care hospital. Five hundred and forty-eight cases of E. coli (75%) and 183 cases of K. pneumoniae (25%) were analyzed. Urinary tract infection (43.1%) was most common, followed by intra-abdominal infection (39%) and pneumonia (7.2%). Trimethoprim/sulfamethoxazole, fluoroquinolone, third-generation cephalosporin (3GC) and amikacin resistance rates among E. coli and K. pneumoniae were 22.8%, 19.6%, 6.2%, and 1.3%, respectively. In 2009, the rate of 3GC resistance (10.6%) was significantly higher, compared to the annual averages of 2003 to 2008 (6.1%; p = 0.03). Previous exposure to antibiotics was an independent risk factor for 3GC resistance in multivariate logistic regression analysis.

CONCLUSIONS

The rate of 3GC resistance increased in community-onset infections, and previous exposure to antibiotics was an independent risk factor. Despite the increased 3GC resistance in community-onset infections, an amikacin combination therapy could provide an option for treatment of bacteremic patients with previous antibiotic exposure in an ED.

An outbreak of Burkholderia cenocepacia associated with contaminated chlorhexidine solutions prepared in the hospital

From October to December 2007, an outbreak of Burkholderia cenocepacia occurred in a secondary care hospital. The 19 B cenocepacia isolated from the patients, the chlorhexidine solutions of each different ward, and the purified water that diluted these solutions exhibited an identical pulsed-field gel electrophoresis pattern. Inadequate preparation of chlorhexidine solutions diluted with contaminated purified water may have resulted in an outbreak of B cenocepacia. Adequate preparation of chlorhexidine solutions should be emphasized.

Impact of extended-spectrum beta-lactamase on acute pyelonephritis treated with empirical ceftriaxone

BACKGROUND

Ceftriaxone is frequently administered empirically for hospitalized patients with acute pyelonephritis (APN) due to prevalent quinolone resistance in our hospital; however, its use is inappropriate for extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli, an increasing problem.

METHODS

A retrospective, 1:2 matched cohort study was performed to evaluate the impact of ESBL on APN treated with empirical ceftriaxone. Each patient in ESBL group was matched with two patients in the non-ESBL group, using a 16-point scoring system, which included age, sex, bacteremia, simplified acute physiology score 2, Charlson comorbidity index and APN severity score.

RESULTS

From 2009 to 2011, among 1,322 community-onset cases of the E. coli bacteriuria with 212 (16%) ESBL producers, 261 patients with APN were treated empirically with ceftriaxone in a secondary care hospital. Among these 261 cases, twenty-six patients in the ESBL group and 52 matched patients in the non-ESBL group (1:2) were included. Mean time to defervescence was 4.6±2.2 days in the ESBL group and 2.6±1.3 days in the non-ESBL group (p<0.01). Rate of microbiological resolution within 5 days after antibiotic treatment was 77% (17/22) in the ESBL group and 100% (45/45) in the non-ESBL group (p=0.01). The duration of hospitalization was 13.3±8.2 days in the ESBL group and 7.3±3.5 days in the non-ESBL group (p<0.01). No patient died in either group.

CONCLUSION

Empirical ceftriaxone therapy for APN caused by ESBL-producing E. coli is inappropriate, and consequently can delay recovery and result in longer hospitalization.

Tissue biomarkers for prostate cancer radiation therapy

Prostate cancer is the most common cancer and second leading cause of cancer deaths among men in the United States. Most men have localized disease diagnosed following an elevated serum prostate specific antigen test for cancer screening purposes. Standard treatment options consist of surgery or definitive radiation therapy directed by clinical factors that are organized into risk stratification groups. Current clinical risk stratification systems are still insufficient to differentiate lethal from indolent disease. Similarly, a subset of men in poor risk groups need to be identified for more aggressive treatment and enrollment into clinical trials. Furthermore, these clinical tools are very limited in revealing information about the biologic pathways driving these different disease phenotypes and do not offer insights for novel treatments which are needed in men with poor-risk disease. We believe molecular biomarkers may serve to bridge these inadequacies of traditional clinical factors opening the door for personalized treatment approaches that would allow tailoring of treatment options to maximize therapeutic outcome. We review the current state of prognostic and predictive tissue-based molecular biomarkers which can be used to direct localized prostate cancer treatment decisions, specifically those implicated with definitive and salvage radiation therapy.

Alcohol intake and renal cell cancer risk: a meta-analysis

BACKGROUND

An inverse association between alcoholic beverage intake and risk of renal cell cancer has been suggested in recent studies.

METHODS

We examined the association between alcoholic beverages and renal cell cancer risk in a meta-analysis. We identified relevant studies by searching the database of PubMed, EMBASE, and MEDLINE published through August 2011. We combined the study-specific relative risks (RRs) using a random-effects model.

RESULTS

A total of 20 case-control studies, 3 cohort studies, and 1 pooled analysis of cohort studies were included in the meta-analysis. We observed that alcoholic beverage intake was associated with a lower risk of renal cell cancer in combined analysis of case-control and cohort studies; for total alcoholic beverage intake, combined RRs (95% confidence intervals) comparing top with bottom categories were 0.76 (0.68-0.85) in case-control studies, and 0.71 (0.63-0.78) in cohort studies (P for difference by study design=0.02). The inverse associations were observed for both men and women and for each specific type alcoholic beverage (beer, wine, and liquor). Also, we found that one drink per day of alcoholic beverage conferred the reduction in renal cell cancer risk, but further drinking above that level did not add benefit.

CONCLUSION

The findings from our meta-analysis support the hypothesis that alcoholic beverage intake is inversely associated with a lower risk of renal cell cancer, with moderate consumption conferring the protection and higher consumption conferring no additional benefits.

Technical note: unsupervised C-arm pose tracking with radiographic fiducial

PURPOSE

C-arm fluoroscopy reconstruction, such as that used in prostate brachytherapy, requires that the relative poses of the individual C-arm fluoroscopy images must be known prior to reconstruction. Radiographic fiducials can provide excellent C-arm pose tracking, but they need to be segmented in the image. The authors report an automated and unsupervised method that does not require prior segmentation of the fiducial.

METHODS

The authors compute the individual C-arm poses relative to a stationary radiographic fiducial of known geometry. The authors register a filtered 2D fluoroscopy image of the fiducial to its 3D model by using image intensity alone without prior segmentation. To enhance the C-arm images, the authors investigated a three-step cascade filter and a line enhancement filter. The authors tested the method on a composite fiducial containing beads, straight lines, and ellipses. Ground-truth C-arm pose was provided by a clinically proven method.

RESULTS

Using 111 clinical C-arm images and +/- 10 degrees and +/- 10 mm random perturbation around the ground-truth pose, a total of 2775 cases were evaluated. The average rotation and translation errors were 0.62 degrees (STD = 0.31 degrees) and 0.72 mm (STD = 0.55 mm) for the three-step filter and 0.67 degrees (STD = 0.40 degrees) and 0.87 mm (STD = 0.27 mm) using the line enhancement filter.

CONCLUSIONS

The C-arm pose tracking method was sufficiently accurate and robust on human patient data for subsequent 3D implant reconstruction.

Registration between ultrasound and fluoroscopy or CT in prostate brachytherapy

PURPOSE

In prostate brachytherapy, transrectal ultrasound (TRUS) is used to visualize the anatomy, while implanted seeds can be visualized by fluoroscopy. Intraoperative dosimetry optimization is possible using a combination of TRUS and fluoroscopy, but requires localization of the fluoroscopy-derived seed cloud, relative to the anatomy as seen on TRUS. The authors propose to develop a method of registration of TRUS images and the implants reconstructed from fluoroscopy.

METHODS

A phantom was implanted with 48 seeds then imaged with TRUS and CT. Seeds were reconstructed from CT yielding a cloud of seeds. Fiducial-based ground-truth registration was established between the TRUS and CT. TRUS images are filtered, compounded, and registered to the reconstructed implants by using an intensity-based metric. The authors evaluated a volume-to-volume and point-to-volume registration scheme. In total, seven TRUS filtering techniques and three image similarity metrics were analyzed. The method was also tested on human subject data captured from a brachytherapy procedure.

RESULTS

For volume-to-volume registration, noise reduction filter and normalized correlation metrics yielded the best result: An average of 0.54 +/- 0.11 mm seed localization error relative to ground truth. For point-to-volume registration, noise reduction combined with beam profile filter and mean squares metrics yielded the best result: An average of 0.38 +/- 0.19 mm seed localization error relative to the ground truth. In human patient data, C-arm fluoroscopy images showed 81 radioactive seeds implanted inside the prostate. A qualitative analysis showed clinically correct agreement between the seeds visible in TRUS and reconstructed from intraoperative fluoroscopy imaging. The measured registration error compared to the manually selected seed locations by the clinician was 2.86 +/- 1.26 mm.

CONCLUSIONS

Fully automated registration between TRUS and the reconstructed seeds performed well in ground-truth phantom experiments and qualitative observation showed adequate performance on early clinical patient data.

Molecular characterization of Pseudomonas aeruginosa isolates resistant to all antimicrobial agents, but susceptible to colistin, in Daegu, Korea

Multi-drug resistant Pseudomonas aeruginosa has been implicated in a variety of serious therapeutic problems in clinical environments. Among the 968 P. aeruginosa isolates obtained from two hospitals in Daegu, Korea, we acquired 17 isolates that were resistant to all available tested antimicrobial agents, with the exception of colistin (colistin-only sensitive). We characterized the antimicrobial susceptibilities, metallo-beta-lactamases, and epidemiological relatedness among the colistin-only sensitive P. aeruginosa isolates. All colistin-only sensitive isolates were positive in the modified Hodge test and imipenem-EDTA synergy test, thereby indicating the production of metallo-beta-lactamases. 11 isolates from the secondary hospital and six isolates from the tertiary teaching hospital harbored blaVIM-2 and blaIMP-1, respectively. The pulsed-field gel electrophoretic analysis of the SpeI-digested DNA from P. aeruginosa isolates indicated that two different clones of colistin-only sensitive P. aeruginosa originated from each hospital, and had spread within the hospital environment. Overall, colistin-only sensitive P. aeruginosa was detected in Korea for the first time, but no pan-drug resistant bacteria were identified. Nationwide surveillance is required in order to monitor the emergence of colistin-only sensitive or pan-drug resistant bacteria.

Differences in phenotypic and genotypic traits against antimicrobial agents between Acinetobacter baumannii and Acinetobacter genomic species 13TU

OBJECTIVES

To investigate the differences in antimicrobial susceptibility and resistance mechanisms against imipenem between Acinetobacter baumannii and Acinetobacter genomic species 13TU.

METHODS

A total of 232 non-duplicate Acinetobacter species were consecutively collected from two Korean hospitals in Daegu, Republic of Korea, between November 2004 and November 2005. Antimicrobial susceptibility was determined by agar dilution methods. Resistance to imipenem was characterized by a carbapenemase activity test and PCR amplification. PFGE was performed to determine the clonal relatedness of imipenem-resistant Acinetobacter species.

RESULTS

A. baumannii was the most prevalent species (61.2%), followed by Acinetobacter genomic species 13TU (25.9%). The resistance rates of A. baumannii to most antimicrobial agents were higher than those of other Acinetobacter species, while the resistance rate to imipenem was the highest in Acinetobacter genomic species 13TU. Imipenem-resistant Acinetobacter genomic species 13TU isolates produced VIM-2 metallo-beta-lactamase, while imipenem-resistant A. baumannii isolates produced OXA-23 and/or OXA-51 beta-lactamase. Imipenem-resistant Acinetobacter strains originated from different clones in each hospital.

CONCLUSIONS

Two prevalent Acinetobacter species, A. baumannii and Acinetobacter genomic species 13TU, possess distinct phenotypic and genotypic traits against antimicrobials.

Expression of Ku80 correlates with sensitivities to radiation in cancer cell lines of the head and neck

The Ku protein is essential for the repair of a majority of DNA double-strand breaks in mammalian cells. The purpose of this study was to investigate the relationship between the expression of Ku70/80 and sensitivity to radiation in cancer cell lines of the head and neck. The sensitivity to radiation in various head and neck cancer cell lines (AMC-HN-1 to -9) was analyzed by colony forming assay. Of the nine cell lines examined, the most radiosensitive cell line (AMC-HN-3) and the most radioresistant cell line (AMC-HN-9) were selected for this experiments. The expression of Ku70/80 was examined after irradiation using real time PCR, Western blotting and immunofluorescence in two different cell lines. Cell cycle distribution after irradiation were analysed. A differential radioresponse was demonstrated by expression of Ku70/80 in AMC-HN-3 and AMC-HN-9 cells. While the expression of Ku70 was slightly increased in the radioresistant AMC-HN-9 cell line, the expression of Ku80 was remarkably increased, suggesting a correlation between Ku80 expression and radiation resistance. Overexpression of Ku80 plays an important role in the repair of DNA damage induced by radiation. Ku80 expression may provide an effective predictive assay of radiosensitivity in head and neck cancers.

Hydrothermal Synthesis of Zn2SnO4 as Anode Materials for Li-Ion Battery

Spinel Zn2SnO4 particles with the cubic shape are prepared via a hydrothermal reaction under mild conditions. The hydrothermal conditions, such as alkaline concentration, reaction temperature, and duration time, have an important influence on the product structure and the performance of the electrode prepared with the product. The optimized product is cube-shaped Zn2SnO4 crystalline, which is prepared with 0.4 M of NaOH solution at 200 degrees C for 24 h. These cube-shaped Zn2SnO4 particles with the spinel structure exhibit a large electrochemical capacity of 988 mA h/g and a relatively good capacity retention as anode materials for Li-ion battery. The structures of the as-prepared product and specimens taken from the electrodes after charging-discharging cycles are analyzed by X-ray diffraction, scanning electron microscopy, and transition electron microscopy techniques. In particular, it is found for the first time that the spinel Zn2SnO4 structure exists to a great extent after the first cycle and contributes to the extremely high reversible capacity during the following cycles.

Praseodymium Hydroxide and Oxide Nanorods and Au/Pr6O11 Nanorod Catalysts for CO Oxidation

Praseodymium hydroxide nanorods were synthesized by a two-step approach: First, metallic praseodymium was used to form praseodymium chloride, which reacted subsequently with KOH solution to produce praseodymium hydroxide. In the second step the hydroxide was treated with a concentrated alkaline solution at 180 degrees C for 45 h, yielding nanorods as shown by the scanning and transmission electron microscopy images. The results of X-ray diffraction and energy-dispersive X-ray spectroscopy experiments indicate that these nanorods are pure praseodymium hydroxide with a hexagonal structure, which can be converted into praseodymium oxide (Pr6O11) nanorods of a face-centered cubic structure after calcination at 600 degrees C for 2 h in air. Gold was loaded on the praseodymium oxide nanorods using HAuCl4 as the gold source, and NaBH4 was used to reduce the gold species to metallic nanoparticles with sizes of 8-12 nm on the nanorod surface. These Au/Pr6O11 nanorods exhibit superior catalytic activity for CO oxidation.

CeO2 Nanorods and Gold Nanocrystals Supported on CeO2 Nanorods as Catalyst

The formation mechanism of uniform CeO2 structure at the nanometer scale via a wet-chemical reaction is of great interest in fundamental study as well as a variety of applications. In this work, large-scale well-crystallized CeO2 nanorods with uniform diameters in the range of 20-30 nm and lengths up to tens of micrometers are first synthesized through a hydrothermal synthetic route in 5 M KOH solution at 180 degrees C for 45 h without any templates and surfactants. The nanorod formation involves dehydration of CeO2 nanoparticles and orientation growth along the 110 direction in KOH solution. Subsequently, gold nanoparticles with crystallite sizes between 10 and 20 nm are loaded on the surface of CeO2 nanorods using HAuCl4 solution as the gold source and NaBH4 solution as a reducing agent. The synthesized Au/CeO2 nanorods demonstrate a higher catalytic activity in CO oxidation than the pure CeO2 nanorods.

Phase transition between nanostructures of titanate and titanium dioxides via simple wet-chemical reactions

Titanate nanofibers of various sizes and layered structure were prepared from inorganic titanium compounds by hydrothermal reactions. These fibers are different from "refractory" mineral substances because of their dimension, morphology, and significant large ratio of surface to volume, and, surprisingly, they are highly reactive. We found, for the first time, that phase transitions from the titanate nanostructures to TiO(2) polymorphs take place readily in simple wet-chemical processes at temperatures close to ambient temperature. In acidic aqueous dispersions, the fibers transform to anatase and rutile nanoparticles, respectively, but via different mechanisms. The titanate fibers prepared at lower hydrothermal temperatures transform to TiO(2) polymorphs at correspondingly lower temperatures because they are thinner, possess a larger surface area and more defects, and possess a less rigid crystal structure, resulting in lower stability. The transformations are reversible: in this case, the obtained TiO(2) nanocrystals reacted with concentrate NaOH solution, yielding hollow titanate nanotubes. Consequently, there are reversible transformation pathways for transitions between the titanates and the titanium dioxide polymorphs, via wet-chemical reactions at moderate temperatures. The significance of these findings arises because such transitions can be engineered to produce numerous delicate nanostructures under moderate conditions. To demonstrate the commercial application potential of these processes, we also report titanate and TiO(2) nanostructures synthesized directly from rutile minerals and industrial-grade rutiles by a new scheme of hydrometallurgical reactions.

Preparation and Electrochemical Hydrogen Storage of Boron Nitride Nanotubes

Boron nitride (BN) nanotubes were synthesized through chemical vapor deposition over a wafer made by a LaNi5/B mixture and nickel powder at 1473 K. Scanning electron microscopy, transmission electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were performed to characterize the microstructure and composition of BN nanotubes. It was found that the obtained BN nanotubes were straight with a diameter of 30-50 nm and a length of up to several microns. We first verify that the BN nanotubes can storage hydrogen by means of an electrochemical method, though its capacity is low at present. The hydrogen desorption of nonelectrochemical recombination in cyclic voltammograms, which is considered as the slow reaction at BN nanotubes, suggests the possible existence of strong chemisorption of hydrogen, and it may lead to the lower discharge capacity of BN nanotubes. It is tentatively concluded that the improvement of the electrocatalytic activity by surface modification with metal or alloy would enhance the electrochemical hydrogen storage capacity of BN nanotubes.

Phase transition between nanostructures of titanate and titanium dioxides via simple wet-chemical reactions

Titanate nanofibers of various sizes and layered structure were prepared from inorganic titanium compounds by hydrothermal reactions. These fibers are different from "refractory" mineral substances because of their dimension, morphology, and significant large ratio of surface to volume, and, surprisingly, they are highly reactive. We found, for the first time, that phase transitions from the titanate nanostructures to TiO(2) polymorphs take place readily in simple wet-chemical processes at temperatures close to ambient temperature. In acidic aqueous dispersions, the fibers transform to anatase and rutile nanoparticles, respectively, but via different mechanisms. The titanate fibers prepared at lower hydrothermal temperatures transform to TiO(2) polymorphs at correspondingly lower temperatures because they are thinner, possess a larger surface area and more defects, and possess a less rigid crystal structure, resulting in lower stability. The transformations are reversible: in this case, the obtained TiO(2) nanocrystals reacted with concentrate NaOH solution, yielding hollow titanate nanotubes. Consequently, there are reversible transformation pathways for transitions between the titanates and the titanium dioxide polymorphs, via wet-chemical reactions at moderate temperatures. The significance of these findings arises because such transitions can be engineered to produce numerous delicate nanostructures under moderate conditions. To demonstrate the commercial application potential of these processes, we also report titanate and TiO(2) nanostructures synthesized directly from rutile minerals and industrial-grade rutiles by a new scheme of hydrometallurgical reactions.

Rotor-like ZnO by epitaxial growth under hydrothermal conditionsElectronic supplementary information (ESI) available: TEM images of the rod-like and rotor-like ZnO in the bright field and dark field. See http://www.rsc.org/suppdata/cc/b4/b403252g/

Rotor-like ZnO was grown from a mixture of rod-like ZnO powder and a saturated Zn(OH)(4)(2-) solution under moderate hydrothermal conditions at 100 degree C, in which the precursor rod-like ZnO crystal plane acts as a matrix core, and the branched nanorods showed fast epitaxial growth on the six directions around the prism core.

Phase I study of escalating doses of low-dose-rate, locoregional irradiation preceding Cytoxan-TBI for patients with chemotherapy-resistant non-Hodgkin's or Hodgkin's lymphoma

PURPOSE

In patients in whom bone marrow transplantation (BMT) fails, recurrence often occurs at sites known to have contained disease before initiating BMT. The purpose of this study was to find the maximal tolerable dose of locoregional irradiation (LRT) between 1000 and 2000 cGy that could be integrated with our Cytoxan-total body irradiation (TBI) BMT conditioning regimen in the treatment of lymphoma.

METHODS AND MATERIALS

Patients had Hodgkin's or non-Hodgkin's lymphoma in chemotherapy-refractory relapse. All patients received LRT to a maximum of three sets of fields encompassing either all current or all previously known sites of disease. Cytoxan-TBI consisted of cyclophosphamide 50 mg/kg daily for 4 days followed by TBI of 1200 cGy given in four fractions.

RESULTS

Twenty-one patients were enrolled. Radiation Therapy Oncology Group Grade 3 in-field acute toxicity was observed in 1 patient at each dose level up to 1500 cGy and in 3 of 6 patients receiving 2000 cGy. Clinically evident late toxicities were limited to hypothyroidism and one second malignancy occurring outside the LRT fields.

CONCLUSION

Low-dose-rate, LRT with concurrent Cytoxan-TBI before BMT has acceptable rates of in-field toxicity for doses up to 1500 cGy in five fractions. This regimen safely permits the use of a total combined radiation dose of up to 2700 cGy during 2 weeks, with encouraging in-field response rates in treatment-refractory patients.

Acute and late radiotherapy toxicity in patients with inflammatory bowel disease

PURPOSE

To evaluate the incidence of gastrointestinal complications in patients with inflammatory bowel disease (IBD) receiving radiotherapy (RT) and to identify possibly avoidable factors associated with these complications.

METHODS AND MATERIALS

Twenty-four patients were identified and their records reviewed; all had a history of IBD before receiving RT to fields encompassing some portion of the gastrointestinal tract (Crohn's disease) or to the abdomen or pelvis (ulcerative colitis or IBD not otherwise specified).

RESULTS

Five of 24 patients (21%) experienced Grade > or =3 acute gastrointestinal toxicity; all 5 received concurrent chemotherapy. Two of 24 patients (8%) experienced Grade > or =3 late gastrointestinal toxicity. There were no significant correlations between complications and IBD type, prior IBD-related surgery, use of medications for IBD, or status of IBD.

CONCLUSION

Patients with IBD may have an increased risk for severe acute RT-related gastrointestinal complications that is more modest than generally perceived, because all patients who had Grade > or =3 acute complications in this study had received concurrent chemotherapy (p = 0.04). Further study is needed to assess this risk, as well as the impact of RT on these patients' future gastrointestinal morbidity.

4 x 10 Gb/s terrestrial optical free space transmission over 1.2 km using an EDFA preamplifier with 100 GHz channel spacing

We demonstrate a transmission of 4 x 10 Gb/s WDM channels over 1.2 km of free space in 1.55-microm band. The transmitted beam is coupled into a single-mode fiber through a fiber-pigtailed collimator, which enables the use of standard 100-GHz channel spacing and an optical preamplifier at the receiver. All the received channels have Q values higher than 6.

Fractionated stereotactic radiosurgery for treatment of acoustic neuromas

BACKGROUND

Microsurgery and single-fraction radiosurgery for acoustic neuromas are associated with high rates of control, but can result in facial palsy and trigeminal neuropathy. To reduce the morbidity of treatment for acoustic neuromas while maintaining efficacy, we explored fractionated stereotactic radiosurgery (FSR).

METHODS

We reviewed data for 31 acoustic neuromas in 30 patients treated with 25 Gy (linear accelerator) given in 5 consecutive daily fractions. The minimum follow-up was 6 months (6-44 months). The mean tumor volume was 1.1 cm(3) (0.1-8.74 cm(3)).

RESULTS

All tumors remain controlled (9 smaller, 22 unchanged). No patient has experienced post-radiosurgery facial motor dysfunction. Two patients developed new trigeminal neuropathy; 2 patients with preexisting trigeminal nerve symptoms had improvement after FSR. Balance improved in 3 patients, was unchanged in 20 and worsened in 7 patients. Of the 12 patients with useful hearing (PTA < or = 50 dB) prior to treatment, 9 patients retained useful hearing following FSR. Subjectively, of 25 patients with any hearing prior to treatment, 2 had improvement, 10 remained unchanged and 13 had worsening.

CONCLUSIONS

Short course FSR for acoustic neuromas results in acceptable toxicity and may provide high control of tumors. Longer follow-up is needed to assess outcomes.

Geometric phase, Hannay's angle, and an exact action variable

Canonical structure of a generalized time-periodic harmonic oscillator is studied by finding the exact action variable (invariant). Hannay's angle is defined if closed curves of constant action variables return to the same curves in phase space after a time evolution. The condition for the existence of Hannay's angle turns out to be identical to that for the existence of a complete set of (quasi)periodic wave functions. Hannay's angle is calculated, and it is shown that Berry's relation of semiclassical origin on geometric phase and Hannay's angle is exact for the cases considered.

Cardiopulmonary effects of desflurane in ponies, after induction of anaesthesia with xylazine and ketamine

Cardiopulmonary parameters were measured in 12 ponies (small horses) before anaesthesia and, following induction with xylazine and ketamine, during maintenance of anaesthesia with desflurane. In six of the ponies (group A) anaesthesia was maintained for three hours with desflurane at an end-tidal concentration of 7.4 per cent. In the other six ponies (group B), anaesthesia was maintained in the same way for one hour and then the effects of end-tidal desflurane concentrations of 7.4 per cent and 9.6 per cent with and without artificial ventilation were investigated. In group A ponies the arterial blood pressure and the systemic vascular resistance index (SVRI) decreased significantly during the first 45 minutes of anaesthesia but recovered with time. The cardiac index and heart rates were unchanged throughout the measurement period but arterial carbon dioxide tensions increased significantly. In group B ponies, with either mode of ventilation, increasing desflurane concentration resulted in decreases in arterial blood pressure, cardiac index and mixed venous oxygen tension, although the changes were not always statistically significant. There were marked individual differences in the cardiovascular responses to the high desflurane concentrations, the minimum mean arterial blood pressure ranging from 35 to 62 mm Hg, and the cardiac index from 23 to 50 ml/kg/min. The study concludes that during maintenance of anaesthesia with end tidal concentrations of desflurane of 7.4 per cent, cardiac index is well maintained and the initial fall in arterial blood pressures results from a fall in SVRI. However, increasing the concentration of desflurane causes a fall in blood pressure due to cardiac depression.