Observation of Structures in the Processes e^{+}e^{-}→ωχ_{c1} and ωχ_{c2}

We present measurements of the Born cross sections for the processes e^{+}e^{-}→ωχ_{c1} and ωχ_{c2} at center-of-mass energies sqrt[s] from 4.308 to 4.951 GeV. The measurements are performed with data samples corresponding to an integrated luminosity of 11.0  fb^{-1} collected with the BESIII detector operating at the Beijing Electron Positron Collider storage ring. Assuming the e^{+}e^{-}→ωχ_{c2} signals come from a single resonance, the mass and width are determined to be M=(4413.6±9.0±0.8)  MeV/c^{2} and Γ=(110.5±15.0±2.9)  MeV, respectively, which is consistent with the parameters of the well-established resonance ψ(4415). In addition, we also use one single resonance to describe the e^{+}e^{-}→ωχ_{c1} line shape and determine the mass and width to be M=(4544.2±18.7±1.7)  MeV/c^{2} and Γ=(116.1±33.5±1.7)  MeV, respectively. The structure of this line shape, observed for the first time, requires further understanding.

Coupled-Channel Analysis of the χ_{c1}(3872) Line Shape with BESIII Data

We perform a study of the χ_{c1}(3872) line shape using the data samples of e^{+}e^{-}→γχ_{c1}(3872), χ_{c1}(3872)→D^{0}D[over ¯]^{0}π^{0}, and π^{+}π^{-}J/ψ collected with the BESIII detector. The effects of the coupled channels and the off-shell D^{*0} are included in the parametrization of the line shape. The line shape mass parameter is obtained to be M_{X}=(3871.63±0.13_{-0.05}^{+0.06})  MeV. Two poles are found on the first and second Riemann sheets corresponding to the D^{*0}D[over ¯]^{0} branch cut. The pole location on the first sheet is much closer to the D^{*0}D[over ¯]^{0} threshold than the other, and is determined to be 7.04±0.15_{-0.08}^{+0.07}  MeV above the D^{0}D[over ¯]^{0}π^{0} threshold with an imaginary part -0.19±0.08_{-0.19}^{+0.14}  MeV.

Observation of the Anomalous Shape of X(1840) in J/ψ→γ3(π^{+}π^{-}) Indicating a Second Resonance Near pp[over ¯] Threshold

Using a sample of (10087±44)×10^{6}  J/ψ events, which is about 45 times larger than that was previously analyzed, a further investigation on the J/ψ→γ3(π^{+}π^{-}) decay is performed. A significant distortion at 1.84  GeV/c^{2} in the line shape of the 3(π^{+}π^{-}) invariant mass spectrum is observed for the first time, which could be resolved by two overlapping resonant structures, X(1840) and X(1880). The new state X(1880) is observed with a statistical significance larger than 10σ. The mass and width of X(1880) are determined to be 1882.1±1.7±0.7  MeV/c^{2} and 30.7±5.5±2.4  MeV, respectively, which indicates the existence of a pp[over ¯] bound state.

Observation of D^{+}→K_{S}^{0}a_{0}(980)^{+} in the Amplitude Analysis of D^{+}→K_{S}^{0}π^{+}η

We perform for the first time an amplitude analysis of the decay D^{+}→K_{S}^{0}π^{+}η and report the observation of the decay D^{+}→K_{S}^{0}a_{0}(980)^{+} using 2.93  fb^{-1} of e^{+}e^{-} collision data taken at a center-of-mass energy of 3.773 GeV with the BESIII detector. As the only W-annihilation-free decay among D to a_{0}(980) pseudoscalar, D^{+}→K_{S}^{0}a_{0}(980)^{+} is the ideal decay in extracting the contributions of the W-emission amplitudes involving a_{0}(980) and to study the final-state interactions. The absolute branching fraction of D^{+}→K_{S}^{0}π^{+}η is measured to be (1.27±0.04_{stat}±0.03_{syst})%. The branching fractions of intermediate processes D^{+}→K_{S}^{0}a_{0}(980)^{+} with a_{0}(980)^{+}→π^{+}η and D^{+}→π^{+}K[over ¯]_{0}^{*}(1430)^{0} with K[over ¯]_{0}^{*}(1430)^{0}→K_{S}^{0}η are measured to be (1.33±0.05_{stat}±0.04_{syst})% and (0.14±0.03_{stat}±0.01_{syst})%, respectively.

Observation of Significant Flavor-SU(3) Breaking in the Kaon Wave Function at 12<Q^{2}<25 GeV^{2} and Discovery of the Charmless Decay ψ(3770)→K_{S}^{0}K_{L}^{0}

We present cross sections for the reaction e^{+}e^{-}→K_{S}^{0}K_{L}^{0} at center-of-mass energies ranging from 3.51 to 4.95 GeV using data samples collected in the BESIII experiment, corresponding to a total integrated luminosity of 26.5  fb^{-1}. The ratio of neutral-to-charged kaon form factors at large momentum transfers (12 Collapse

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Investigation of the ΔI=1/2 Rule and Test of CP Symmetry through the Measurement of Decay Asymmetry Parameters in Ξ^{-} Decays

Using (10087±44)×10^{6}  J/ψ events collected with the BESIII detector, numerous Ξ^{-} and Λ decay asymmetry parameters are simultaneously determined from the process J/ψ→Ξ^{-}Ξ[over ¯]^{+}→Λ(pπ^{-})π^{-}Λ[over ¯](n[over ¯]π^{0})π^{+} and its charge-conjugate channel. The precisions of α_{Λ0} for Λ→nπ^{0} and α[over ¯]_{Λ0} for Λ[over ¯]→n[over ¯]π^{0} compared to world averages are improved by factors of 4 and 1.7, respectively. The ratio of decay asymmetry parameters of Λ→nπ^{0} to that of Λ→pπ^{-}, ⟨α_{Λ0}⟩/⟨α_{Λ-}⟩, is determined to be 0.873±0.012_{-0.010}^{+0.011}, where the first and the second uncertainties are statistical and systematic, respectively. The ratio is smaller than unity more than 5σ, which signifies the existence of the ΔI=3/2 transition in Λ for the first time. Besides, we test for CP symmetry in Ξ^{-}→Λπ^{-} and in Λ→nπ^{0} with the best precision to date.

Determination of the Σ^{+} Timelike Electromagnetic Form Factors

Based on data samples collected with the BESIII detector at the BEPCII collider, the process e^{+}e^{-}→Σ^{+}Σ[over ¯]^{-} is studied at center-of-mass energies sqrt[s]=2.3960, 2.6454, and 2.9000 GeV. Using a fully differential angular description of the final state particles, both the relative magnitude and phase information of the Σ^{+} electromagnetic form factors in the timelike region are extracted. The relative phase between the electric and magnetic form factors is determined to be sinΔΦ=-0.67±0.29(stat)±0.18(syst) at sqrt[s]=2.3960  GeV, ΔΦ=55°±19°(stat)±14°(syst) at sqrt[s]=2.6454  GeV, and 78°±22°(stat)±9°(syst) at sqrt[s]=2.9000  GeV. For the first time, the phase of the hyperon electromagnetic form factors is explored in a wide range of four-momentum transfer. The evolution of the phase along with four-momentum transfer is an important input for understanding its asymptotic behavior and the dynamics of baryons.

Oncology nurses' experiences of providing emotional support for cancer patients: a qualitative study

BACKGROUND

A high percentage of cancer patients may experience emotional distress. Oncology nurses are expected to play an important role in recognizing emotional distress and planning and delivering care that meets the individual needs of each patient. However, few studies have focused on the experiences of clinical nurses in such cases. This study adopted a qualitative research method to gain an in-depth understanding of the experience of nursing staff in caring for cancer patients with emotional distress.

METHODS

A qualitative descriptive design and semi-structured interviews were used in this study. Twenty-one oncology nurses were interviewed, and the qualitative content analysis suggested by Graneheim & Lundman (2004) was used to interpret the data.

RESULTS

Six themes were identified, as follows: (1) dictating the abnormality of emotion, (2) soothing and comforting patients, (3) a lack of psychology knowledge and communication skills, (4) negative impacts of a lack of time, (5) managing emotional labor, and (6) reflecting on the experiences.

CONCLUSION

Hospital administrators should arrange pre-employment education and training as well as on-the-job education to help nurses in caring for cancer patients with emotional distress. They should also focus attention on the personal emotional states of nursing staff in a timely manner and provide psychological support and emotional counseling as necessary.

First Measurement of the Decay Asymmetry in the Pure W-Boson-Exchange Decay Λ_{c}^{+}→Ξ^{0}K^{+}

Based on 4.4  fb^{-1} of e^{+}e^{-} annihilation data collected at the center-of-mass energies between 4.60 and 4.70 GeV with the BESIII detector at the BEPCII collider, the pure W-boson-exchange decay Λ_{c}^{+}→Ξ^{0}K^{+} is studied with a full angular analysis. The corresponding decay asymmetry is measured for the first time to be α_{Ξ^{0}K^{+}}=0.01±0.16(stat)±0.03(syst). This result reflects the noninterference effect between the S- and P-wave amplitudes. The phase shift between S- and P-wave amplitudes has two solutions, which are δ_{p}-δ_{s}=-1.55±0.25(stat)±0.05(syst)  rad or 1.59±0.25(stat)±0.05(syst)  rad.

Measurement of Energy-Dependent Pair-Production Cross Section and Electromagnetic Form Factors of a Charmed Baryon

We study the process e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} at twelve center-of-mass energies from 4.6119 to 4.9509 GeV using data samples collected by the BESIII detector at the BEPCII collider. The Born cross sections and effective form factors (|G_{eff}|) are determined with unprecedented precision after combining the single and double-tag methods based on the decay process Λ_{c}^{+}→pK^{-}π^{+}. Flat cross sections around 4.63 GeV are obtained and no indication of the resonant structure Y(4630), as reported by Belle, is found. In addition, no oscillatory behavior is discerned in the |G_{eff}| energy dependence of Λ_{c}^{+}, in contrast to what is seen for the proton and neutron cases. Analyzing the cross section together with the polar-angle distribution of the Λ_{c}^{+} baryon at each energy point, the moduli of electric and magnetic form factors (|G_{E}| and |G_{M}|) are extracted and separated. For the first time, the energy dependence of the form factor ratio |G_{E}/G_{M}| is observed, which can be well described by an oscillatory function.

Neoadjuvant chemoradiotherapy versus neoadjuvant chemotherapy followed by minimally invasive esophagectomy for locally advanced esophageal squamous cell carcinoma: a prospective multicenter randomized clinical trial

BACKGROUND

Neoadjuvant therapy is recommended for locally advanced esophageal cancer, but the optimal strategy remains unclear. We aimed to evaluate the safety and efficacy of neoadjuvant chemoradiotherapy (nCRT) versus neoadjuvant chemotherapy (nCT) followed by minimally invasive esophagectomy (MIE) for locally advanced esophageal squamous cell carcinoma (ESCC).

PATIENTS AND METHODS

Eligible patients staged as cT3-4aN0-1M0 ESCC were randomly assigned (1 : 1) to the nCRT or nCT group stratified by age, cN stage, and centers. The chemotherapy, based on paclitaxel and cisplatin, was administered to both groups, while concurrent radiotherapy was added for the nCRT group; then MIE was carried out. The primary endpoint was 3-year overall survival. This study is registered with ClinicalTrials.gov (NCT03001596).

RESULTS

A total of 264 patients were eligible for the intention-to-treat analysis. By 30 November 2021, 121 deaths had occurred. The median follow-up was 43.9 months (interquartile range 36.6-49.3 months). The overall survival in the intention-to-treat population was comparable between the nCRT and nCT strategies [hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.58-1.18; P = 0.28], with a 3-year survival rate of 64.1% (95% CI 56.4% to 72.9%) versus 54.9% (95% CI 47.0% to 64.2%), respectively. There were also no differences in progression-free survival (HR 0.83, 95% CI 0.59-1.16; P = 0.27) and recurrence-free survival (HR 1.07, 95% CI 0.71-1.60; P = 0.75), although the pathological complete response in the nCRT group (31/112, 27.7%) was significantly higher than that in the nCT group (3/104, 2.9%; P < 0.001). Besides, a trend of lower risk of recurrence was observed in the nCRT group (P = 0.063), while the recurrence pattern was similar (P = 0.802).

CONCLUSIONS

NCRT followed by MIE was not associated with significantly better overall survival than nCT among patients with cT3-4aN0-1M0 ESCC. The results underscore the pending issue of the best strategy of neoadjuvant therapy for locally advanced bulky ESCC.

[Clinical value of routine contrast esophagram in the diagnosis of anastomotic leakage for three-incision esophagectomy with cervical anastomosis]

Objective: To examine the clinical value of routine contrast esophagram (RCE) for the diagnosis of anastomotic leakage (AL) after three-incision esophagectomy with cervical anastomosis. Methods: Clinical data of 1 022 patients with esophageal cancer who underwent McKeown three-incision esophagectomy with cervical anastomosis from January 2015 to December 2019 at Department of Minimally Invasive Esophageal Surgery, Tianjin Medical University Cancer Hospital and Institute were analyzed retrospectively. There were 876 males and 146 females, aging(M(IQR)) 48(16) years (range: 36 to 84 years). There were 253 patients (24.8%) with neoadjuvant therapy, and 817 patients (79.9%) with minimally invasive esophagectomy. According to the diagnosis and treatment habits of the attending surgeons, 333 patients were included in the RCE group, and RCE was performed on the 7^th day postoperative, while 689 patients were included in the non-RCE group, and RCE was performed when the patients had suspicious symptoms. Taking clinical symptoms, RCE, CT, endoscopy and other methods as reference to the diagnosis of AL, the sensitivity and specificity were used to analyze and evaluate the efficacy of RCE for the diagnosis of AL. The data were compared by U test or χ² test between groups. Results: The incidence rate of AL after three-incision esophagectomy was 7.34% (75/1 022), including 30 cases in the RCE group and 45 cases in the non-RCE group (9.0%(30/333) vs. 6.5%(45/689), χ²=2.027, P=0.155). The diagnostic time of AL was 9(5) days postoperative (range: 4 to 30 days). Among them, 23 cases showed cervical leakages, 50 cases showed intro-thoracic leakages, and 2 cases both cervical and intro-thoracic leakages. The diagnostic time of patients with intro-thoracic leakages was longer than that of cervical leakages (10(4) days vs. 6(3) days, Z=-2.517, P=0.012). Among the 333 patients in the RCE group, 16 cases of RCE indicated leakages including 11 cases of true positive and 5 cases determined to be false positive, while 317 cases indicated no abnormalities including 19 cases developed leakages. The sensitivity and specificity of RCE to detect AL were 36.7%(11/30) and 98.3%(298/333), respectively. The Youden-index was 0.35, and the diagnostic accuracy was 92.8%(309/333). The positive and negative predictive value were 11/16 and 94.0%(298/317), respectively. Conclusions: Routine contrast esophagram after three-incision esophagectomy with cervical anastomosis has low sensitivity and high specificity in the diagnosis of AL. The diagnostic time of AL is the 9^th day after surgery. It is necessary to prolong the observation time clinically, and combine RCE with CT, endoscopy and other inspection methods for diagnosis.

Prevention of underfeeding during enteral nutrition after gastrectomy in adult patients with gastric cancer: an evidence utilization project

BACKGROUND

Enteral nutrition is commonly used in patients with gastric cancer after a partial or full gastrectomy since it is safe to use and nutrient delivery is in line with human physiological characteristics. However, enteral feeding often leads to deficiency, when the actual intake of the patient is lower than the target demand, which seriously affects the recovery of patients.

OBJECTIVE

To implement the best practice for preventing and managing underfeeding during enteral nutrition, and to improve the nutritional status of patients with gastric cancer.

METHODS

The current study was conducted following the Joanna Briggs Institute Practical Application of Clinical Evidence System program. Phase one referred to the development of the project, consisting of the generation of the best evidence, mainly based on literature review and discussions within a panel of experts. Phase two was the implementation of the project, including baseline audit, training of enteral nutrition and change of clinical practice. Phase three was a postimplementation reaudit. The intake of enteral nutrition was observed in the first 3 days, and feeding intolerance of enteral nutrition was observed within the first week of enteral nutrition. Data were collected using self-designed questionnaires. The nutritional status of patients was measured using Patient-Generated Subjective Global Assessment (PG-SGA) at admission, and 1 week after surgery.

RESULTS

A total of 60 patients with gastric cancer and 10 registered nurses were enrolled in this study. The compliance rate for all audit criteria increased postimplementation. The feeding rate of enteral nutrition postimplementation was higher than the baseline audit on the third day, 54.29% (±12.01) vs. 42.89% (±10.63), and the incidence of underfeeding was lower (30%, n = 30) than the baseline audit (76.67%, n = 30). Furthermore, the feeding intolerance postimplementation (26.67%, n = 30) was lower than the baseline audit (76.67%, n = 30) within 1 week of enteral nutrition. The PG-SGA scores were not significantly different between the baseline audit and postimplementation on the day of admission, while the scores were lower postimplementation (12.90 ± 1.47) compared with the baseline audit (14.00 ± 1.82).

CONCLUSION

In this study, we performed an audit of the clinical nursing quality, which can guide nurses to accurately identify obstacles to the implementation of enteral nutrition, and standardize the implementation and management process, thereby improving the quality of nursing and the nutritional status of patients.

RELEVANCE TO CLINICAL PRACTICE

The evidence-based practice might optimize the enteral nutrition process, enhance the efficacy of enteral nutrition, and improve the nutritional status of patients. Medical staff should develop an individualized nutritional support protocol for patients based on the results of nutritional status assessments.

[Lymphocyte activation gene 3 expression on T lymphocyte cell subsets in patients with myelodysplastic syndrome]

Objective: To investigate the expression of Lymphocyte activation gene 3 (LAG3) in myelodysplastic syndromes (MDS) patients. Methods: A total of 16 MDS patients newly diagnosed in Hematology Department of Tianjin Medical University were enrolled from January to November 2019. The healthy control (HC) group includes 16 cases of healthy adults. The expression levels of LAG3 on CD8(+)T cells, CD4(+)T cells and regulatory T cells (Treg) in MDS patients and healthy controls were detected by flow cytometry. Results: A total of 16 patients with MDS were included, including 5 males and 11 females, with a median age of 56 (18-80) years old. HC group includes 16 healthy adults, 8 men and 8 women, with a median age of 40 (17-69) years. There was no statistically significant difference in gender and age composition between the two groups (both P>0.05). The expression of LAG3 on CD8(+)T cells in MDS patients (74.45%±22.31%) was significantly higher than that in HC group (58.78%±14.82%, P<0.05). The LAG3 expression on Treg in MDS patients (64.91%±10.32%) were significantly higher than that of HC group (49.09%±13.58%, P<0.05). There was no statistical difference in LAG3 expression on CD4(+)T cells between the two groups. Conclusion: The expression of LAG3 on CD8(+)T cells and Treg increases in MDS patients than that of healthy people.

[Characteristic and function of peripheral blood mononuclear cells-induced macrophages in patients with myelodysplastic syndrome]

目的

观察骨髓增生异常综合征（MDS）患者单个核细胞诱导的巨噬细胞的功能，分析其与MDS疾病发展的关系。

方法

以2014年9月至2015年12月天津医科大学总医院血液科24例MDS患者为病例组，以15名健康志愿者为正常对照组。收集外周血标本并分离单个核细胞，体外以GM-CSF诱导分化形成巨噬细胞。在光学显微镜下观察巨噬细胞的形态；使用流式细胞术检测巨噬细胞的数量及其表面受体CD206、SIRPα的表达水平；分别采用流式细胞术和免疫荧光显微镜检测巨噬细胞的吞噬功能。

结果

①MDS来源的巨噬细胞形态较正常对照差（形态不规则、细胞体积小、异形明显、无足突、数量减少），MDS外周血单个核细胞转化为巨噬细胞的转化率为（5.17±3.47）%，显著低于正常对照组的（66.18±13.43）%（t=3.529，P=0.001）；②MDS来源的巨噬细胞表面识别受体CD206的表达水平[（9.73±2.59）%]显著低于正常对照组[（51.15±10.82）%]（t=4.551，P<0.001），SIRPα的表达水平[（0.51±0.09）%]显著低于正常对照组[（0.77±0.06）%]（t=2.102，P=0.043）；③MDS来源的巨噬细胞吞噬免疫微球的吞噬指数、吞噬百分率分别为0.45±0.08、（23.69±3.22）%，显著低于正常对照组的0.92±0.07、（42.75±2.13）%（P值均<0.05），MDS来源的巨噬细胞吞噬单个核细胞的吞噬指数（0.24±0.04）显著低于正常对照组（0.48±0.96，t=3.464，P=0.001）。

结论

MDS患者外周血单个核细胞诱导形成巨噬细胞能力下降，吞噬识别受体减少，吞噬能力减弱。

[Application of adaptie statistical iterative reconstruction technology combined with low tube voltage in three phase enhanced low dose liver scanning]

Objective: To explore the application value of adaptive statistical iterative reconstruction (ASIR) combined with low tube voltage in three-stage enhanced low-dose scan of liver. Methods: From March 2017 to November 2017, two groups which each group included 50 patients were randomly selected at the Second Affiliated Hospital of Harbin Medical University with different stages of arterial phase, delayed phase and portal vein scanning. GE Discovery CT 750 HD Liver CT Ⅲ was used during enhanced scanning. A total of 100 patients included 56 males and 44 females, aged 27-73 years old and 42 patients with hepatocellular carcinoma, 44 patients with hepatic hemangioma, and 14 patients with other diseases. The arterial and delayed period of group A patients were scanned with a low dose of 100 kV+ASIR, and the portal vein phase was conventional. Dosage scanning was 120 kV+FPP; the arterial and delayed period of group B was normal dose scanning, 120 kV+FPP, and the portal vein phase was low dose scanning, 100 kV+ASIR. At the same time, FBP reconstruction was used for all low-dose scanning phases to obtain low-dose images under normal reconstruction mode. The objective evaluation index of image quality was analyzed by completely randomized design analysis of variance, and Dunnett-t test was used to compare the two groups. For the subjective evaluation part, the rank sum test of multiple groups was used. Results: ASIR combined with low tube voltage enhanced low dose scanning in the third phase of the liver, and the radiation dose decreased by 37% in the low dose group compared with the normal dose group. There was no statistically significant difference between the low dose group (100 kV+ASIR) and the normal dose group (120 kV+FPP) in subjective image quality evaluation (P>0.05); objective evaluation of image quality except for low dose(100 kV+ASIR) portal stage noise slightly worse than conventional dose group (120 kV+FBP) (low dose 10.86±1.98, conventional dose 9.40±2.12, P<0.05), the other indexes in each period were superior or indifferent to the normal dose group. Conclusion: ASIR technique combined with low tube voltage can be used in the third phase of liver enhanced low-dose scanning and the image quality is improved.

[Study on the transfer mechanism and destructive law of the bacterial antibiotic resistance genes disinfected by chlorination]

Objective: To study the response of Escherichia coli (E. coli) HB101 (plasmid pUC19) and its carried antibiotic resistance genes to the process of cholorination under different environmental conditions. Methods: The E. coli strain was reacted with sodium hypochlorite at the concentration of 0.5, 0.75, 1.00, and 0.55 mg/L, then the residual chlorine and the colonies were detected at the 0.25, 1, 2, 5, 10, 20, and 30 min of the reaction, respectively. The first order disinfection kinetic model and EFH model were used to evaluate the inactivation effect of E. coli (plasmid pUC19) treated by sodium hypochlorite, while the plasmid pUC19 and antibiotic resistance gene amp(r) were detected by PCR method. Besides, the logarithm of Ct (residual chlorine in t) under different concentration were calculated. Results: The temperature and pH value played important roles on the inactivation of E. coli and elimination of plasmid pUC19 and amp(r) under the function of sodium hypochlorite. The Ct value needed for 5-log of E.coli HB101(pUC19) inactivation at 4, 20, 36 ℃ was 11.92, 10.28, 7.67, respectively, and when the pH was in 6.0, 7.0, 8.0, with chloride concentration were 0.75, 0.70, 0.55 mg/L, the Ct value needed for reached to 6.68, 10.28, 15.73 min·mg/L. At pH 7.2 condition, when the temperature was 4, 20, 36 ℃, and chloride concentration were 9, 5, 3 mg/L.The required Ct values to completely destroy the transformation function of free antibiotic resistant plasmids were 36.11, 34.17,16.09 min·mg/L. Sodium hypochlorite disinfection can release free ampr gene and even the transformed plasmid pUC19, and pollute the water body. Only when the Ct value reached 903.03 min·mg/L, the complete ampr gene can be destroyed which was far more exceed the bacterial lethal Ct value. Conclusion: Even if all the antibiotic resistant bacteria were inactivated, the antibiotic resistant plasmids or genes might still maintain complete with the transformable function, which may result in new potential risks of waterborne diseases.

[Comparison of the prognostic value of the seventh and eighth edition of The AJCC Esophageal Cancer Staging System for the patients with stage Ⅱ and Ⅲesophageal squamous cell carcinoma]

Objective: To compare and evaluate the prognostic value of the 7(th) and 8(th) edition of The AJCC Esophageal Cancer Staging System for patients with stage Ⅱ and Ⅲ esophageal squamous cell carcinoma. Methods: The clinical data of 328 esophageal cancer patients who received operation at Department of Esophageal Cancer, Tianjin Tumour Hospital from January 2006 to December 2010 were restrospectively analyzed. There were 63 female and 265 male patients. The mean age was 65 (range: 33 to 87) years. Univariate and multivariate analysis were performed to identify the prognosis factors. Results: The five years overall survival rates among patients with stage Ⅱ and Ⅲ were both significantly different (χ(2)=87.035, 84.730, all P=0.000) according to the 7(th) and 8(th) editions of the TNM staging systems. The five years overall survival rate among patients with stage ⅡB and ⅢA were significantly different (39.6% vs 23.4%, P=0.001) according to the 7(th) edition of the esophageal cancer staging systems.According to the 8(th) edition of the esophageal cancer staging system, the 5 years survival rate of patients with stage ⅡA and ⅡB, ⅢB and Ⅳ was statistically significant (58.5% vs. 35.5%, P=0.040; 18.9% vs. 0, P=0.000). In multivariate analysis, tumor size, T staging, N staging and tumor differentiation (HR=1.592, 95%CI: 1.185 to 2.139, P=0.002; HR=1.519, 95% CI: 1.236 to 1.867, P=0.000; HR=1.647, 95% CI: 1.448 to 1.874, P=0.000; HR=1.404, 95% CI: 1.059 to 1.861, P=0.018) were the main independent prognosis factors affecting the prognosis of esophageal squamous cell carcinoma patients. Conclusions: Both the 7(th) and the 8(th) editions of TNM staging systems are able to reflect the clinical prognosis of patients receiving radical resection of esophageal cancer, and the factors of tumor size, differentiaton, invasion depth and lymph node metastases are the independent predictors of prognosis. The 8(th) edition provides a more detailed and more reasonable for the staging of stage Ⅱ and Ⅲ for esophageal cancer patients than the 7(th) edition, and it is more accurate for the prognosis of patients with esophageal cancer after surgery.

Design of a multiband near-infrared sky brightness monitor using an InSb detector

Infrared sky background level is an important parameter of infrared astronomy observations from the ground, particularly for a candidate site of an infrared capable observatory since low background level is required for such a site. The Chinese astronomical community is looking for a suitable site for a future 12 m telescope, which is designed for working in both optical and infrared wavelengths. However, none of the proposed sites has been tested for infrared observations. Nevertheless, infrared sky background measurements are also important during the design of infrared observing instruments. Based on the requirement, in order to supplement the current site survey data and guide the design of future infrared instruments, a multiband near-infrared sky brightness monitor (MNISBM) based on an InSb sensor is designed in this paper. The MNISBM consists of an optical system, mechanical structure and control system, detector and cooler, high gain readout electronics, and operational software. It is completed and tested in the laboratory. The results show that the sensitivity of the MNISBM meets the requirements of the measurement of near-infrared sky background level of several well-known astronomical infrared observing sites.

[An investigation for standardized diagnosis and treatment of idiopathic normal-pressure hydrocephalus]

OBJECTIVE

To investigate some important issues for diagnosis and treatment of idiopathic normal-pressure hydrocephalus (iNPH), such as standardized pre-operative assessment, initial pressure value of diverter pump, and pressure regulation during follow-up.

METHODS

Twenty six iNPH patients (21 males) who treated in Department of Neurosurgery of 2nd Affiliated Hospital of Zhejiang University School of Medicine from 2011 to 2015 were analyzed retrospectively. The average age was 60.5 year. The analysis focused on the treatment process of iNPH, initial pressure value of diverter pump, choice of diverter pump, and pressure regulation during follow-up.

RESULTS

As a result, 24 cases (92.3%) had a good prognosis based on their imaging and clinical manifestations. Based on the literature and their clinical experiences, this department established a diagnosis and treatment procedure of iNPH and a pressure regulation procedure for the follow-up of iNPH. Moreover, it is proposed that choosing an anti-gravity diverter pump and making an initial pressure value 20 mmH2O less than pre-surgical cerebrospinal pressure may be beneficial for the prognosis.

CONCLUSION

This standardized diagnosis and treatment procedure for iNPH is practical and effective.

Search for a light sterile neutrino at Daya Bay

A search for light sterile neutrino mixing was performed with the first 217 days of data from the Daya Bay Reactor Antineutrino Experiment. The experiment's unique configuration of multiple baselines from six 2.9 GW(th) nuclear reactors to six antineutrino detectors deployed in two near (effective baselines 512 m and 561 m) and one far (1579 m) underground experimental halls makes it possible to test for oscillations to a fourth (sterile) neutrino in the 10(-3) eV(2)<|Δm(41)(2) |< 0.3 eV(2) range. The relative spectral distortion due to the disappearance of electron antineutrinos was found to be consistent with that of the three-flavor oscillation model. The derived limits on sin(2) 2θ(14) cover the 10(-3) eV(2) ≲ |Δm(41)(2)| ≲ 0.1 eV(2) region, which was largely unexplored.

Spectral measurement of electron antineutrino oscillation amplitude and frequency at Daya Bay

A measurement of the energy dependence of antineutrino disappearance at the Daya Bay reactor neutrino experiment is reported. Electron antineutrinos (ν¯(e)) from six 2.9  GW(th) reactors were detected with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls. Using 217 days of data, 41 589 (203 809 and 92 912) antineutrino candidates were detected in the far hall (near halls). An improved measurement of the oscillation amplitude sin(2)2θ(13)=0.090(-0.009)(+0.008) and the first direct measurement of the ν¯(e) mass-squared difference |Δm(ee)2|=(2.59(-0.20)(+0.19))×10(-3)  eV2 is obtained using the observed ν¯(e) rates and energy spectra in a three-neutrino framework. This value of |Δm(ee)2| is consistent with |Δm(μμ)2| measured by muon neutrino disappearance, supporting the three-flavor oscillation model.

Observation of electron-antineutrino disappearance at Daya Bay

The Daya Bay Reactor Neutrino Experiment has measured a nonzero value for the neutrino mixing angle θ(13) with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43,000 ton-GWth-day live-time exposure in 55 days, 10,416 (80,376) electron-antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R=0.940±0.011(stat.)±0.004(syst.). A rate-only analysis finds sin(2)2θ(13)=0.092±0.016(stat.)±0.005(syst.) in a three-neutrino framework.

Experimental Study on Angiogenesis in a Rabbit VX2 Early Liver Tumour by Perfusion Computed Tomography

Ten rabbits implanted with VX2 liver tumours were investigated by perfusion computed tomography (PCT) imaging 1 week (early) and 2 weeks (late) after tumour induction; 10 other rabbits were non-implanted controls. Time–density curves, perfusion parametric maps and perfusion parameters were obtained for tumour rim and normal tissue surrounding the tumour, and for liver tissue from the controls. In addition, microvessel density (MVD) and vascular endothelial growth factor (VEGF) were studied by immunohistochemistry 2 weeks after tumour implantation. A deconvolution mathematical model was used to calculate hepatic blood flow (HBF), hepatic blood volume (HBV), mean transit time (MTT), capillary vessel surface permeability (PS) and hepatic arterial index (HAI). At the tumour rim on the early PCT scan, MTT was significantly lower whereas HBF, HBV, HAI and PS were significantly higher than in surrounding normal tissue. There were no significant changes in perfusion parameters on the late PCT scan compared with the early scan. Significant linear correlations of MVD and VEGF were found with HBF, PS and HAI, but not with HBV or MTT. It is concluded that PCT imaging is useful for the evaluation of tumour angiogenesis and for the early detection of liver tumours.

Complex refractive index measurement of biological tissues by attenuated total reflection ellipsometry

To apply reflection ellipsometry to determine the real and imaginary parts of the refractive index of biological tissues simultaneously, we combine reflection ellipsometry with total internal reflection to warrant minimal influences by the strong scattering and absorption of biological tissues. A K9 glass prism with refractive index 1.51468 at wavelength 632.8 nm and a Glan prism polarizer with an angular sampling interval of 0.1 degrees were used in our experimental setup. Using the setup, the complex refractive indices of some typical mammalian tissues were measured under the wavelength of 632.8 nm. The results show that the indices of porcine muscle, liver, pancreas, and dermis tissues were 1.3713+0.062i, 1.3791+0.0087i, 1.3517+0.0113i, and 1.3818+0.0049i, respectively.

Optimal treatment for distal ureteral calculi: extracorporeal shockwave lithotripsy versus ureteroscopy

BACKGROUND

The optimal treatment for distal ureteral calculi remains controversial. We present data from our institution to compare the efficacy of extracorporeal shockwave lithotripsy (SWL) and ureteroscopy with different lithotripsy modalities (URSL).

METHODS

From January 1994 to September 1997, 954 distal ureteral calculi were treated at our institution using in situ SWL (Siemens Lithostar) in 524 patients and ureteroscopy (Wolf 8.0F instrument and Swiss Lithoclast) in 430 patients. Stone sizes and patient ages were similar in these two groups.

RESULTS

In the SWL group, the 3-month stone-free rate was 87%, and the effectiveness quotient (EQ) was 68.7%. In the URSL group, there was a 96% stone-free rate with an EQ of 92.1%. The SWL treatment was more expensive than URSL.

CONCLUSION

At our institution, ureteroscopy is more efficacious than SWL for the treatment of distal ureteral calculi. In selected patients who had stones >10 mm with evidence of impaction and severe colic pain, we strongly suggest that URSL is the best choice.

Factors influencing hospital implementation of acute pain management practice guidelines

STUDY OBJECTIVE

To identify factors that may influence the implementation of acute pain management guidelines in hospital settings.

DESIGN

Two questionnaire surveys.

SETTING

Healthcare Association of New York State, Albany, NY.

MEASUREMENT

The surveys were administered to 220 hospitals in New York State regarding their acute pain management practices and resources available. One survey was addressed to each hospital's chief executive officer (CEO) and the second survey was addressed to the clinical director of the Department of Anesthesiology or Acute Pain Service. The barriers and incentives to guideline implementation identified by CEOs were analyzed using factor analysis. Logistic regression was employed to determine predictors of guideline implementation by linking the CEOs' survey data with the clinical directors' report of guideline usage.

MAIN RESULTS

According to clinical directors, only 27% of the responding hospitals were using a published pain management practice guideline. Factors predictive of guideline implementation include resource availability and belief in the benefits of using guidelines to improve quality of care or to achieve economic/legal advantages. Guideline implementation, however, does not necessarily include applying all key elements recommended by the federal Agency for Healthcare Research and Quality (formerly Agency for Health Care Policy and Research) guideline. For example, a collaborative, interdisciplinary approach to pain control was used in only 42% of the hospitals, and underutilization of nonpharmacologic therapies to control pain was widespread. Resource availability, particularly staff with expertise in pain management and existence of a formal quality assurance program to monitor pain management, was significantly predictive of compliance with key guideline elements.

CONCLUSIONS

Resource availability significantly influences the implementation of pain management practice guidelines in hospital settings. Implementation is often incomplete because various factors affect the feasibility of individual guideline elements and may explain the varying results that guidelines have had on clinical practices.

Adapting the HCUP QIs for hospital use: the experience in New York State

BACKGROUND

The Agency for Healthcare Research and Quality developed the Healthcare Cost and Utilization Project (HCUP) quality indicators (QIs) in 1994. The Healthcare Association of New York State (HANYS; Albany), which represents more than 500 nonprofit and public hospitals, long-term care facilities, and home health care agencies, has adapted the HCUP QIs since 1997 to produce annual comparative reports for its member hospitals. Specifically designed for internal use, the reports have been well received and have drawn interest from other hospital associations and state health departments.

METHODS

The HCUP QIs were applied to the New York State hospital discharge abstract. A risk adjustment model was constructed for each complication measure. Measures of utilization and access to care were adjusted for differences in patient demographics and payer status by indirect standardization. Data are presented in graphic format. Each hospital receives its own report (in both paper copy and CD-ROM) with comparisons to statewide norms, regional averages, and peer group averages. Report prepared for hospital systems include data for each affiliated hospital.

CONCLUSIONS

When used appropriately, the HCUP QIs provide valuable information for individual hospitals to assess quality of care and target potential areas for improvement. The HCUP QIs also give hospitals a broad perspective to look beyond their own institutions and develop community-based quality improvement initiatives. Nevertheless, given the limitations that commonly exist with administrative databases and the lack of standard risk adjustment systems, the HCUP QIs are best used for internal purposes and not for public reporting.

Do primary care physicians or specialists provide more efficient care?

Sinusitis is a common health complaint and expenditures for its treatment are high; thus, it is necessary to promote efficient practice behaviours in managing patient care. This study compares resource utilization between primary care physicians and specialists in the treatment of Medicaid sinusitis patients in Virginia. Physician-level data from Virginia Medicaid claim files for 1993 were analysed. The efficiency frontier, representing the best achievable performance in the use of resources for treating sinusitis, is identified using Data Envelopment Analysis. Resource utilization (primary care physician visits, specialist visits, emergency room usage, prescriptions and laboratory tests) and corresponding costs are compared between generalists and otolaryngologists. It was concluded from this study that there are no discernible differences in technical efficiency between generalists and specialists in the treatment of sinusitis. Nevertheless, otolaryngologists are found to be more costly than generalists in treating sinusitis. Variation in both caseload and patient mix might explain variation in use of resources.

Synthesis and antimalarial activity of artemisinin derivatives containing an amino group

In search of water-soluble artemisinin derivatives that are more stable than sodium artesunate, over 30 derivatives containing an amino group (compounds 3-5) were synthesized and tested in mice. All products tested (except 5a and 5b) are the beta isomers. These basic compounds combined with organic acids (oxalic acid, maleic acid, etc. ) to yield the corresponding salts. Generally, the maleates have better solubility in water than the corresponding oxalates. The aqueous solutions of these salts can be kept at room temperature for several weeks without any discernible decomposition. Compounds 3f, 3h, and 3r are much more active against P. berghei than artesunic acid by oral administration and therefore were further tested in monkeys. However, their oral efficacies are poorer than that of artesunic acid against P. knowlesi in rhesus monkeys. It is interesting to note that 3f, 3h, and 3r showed much lower efficacies against P. berghei when they were administered subcutaneously than orally.

Regional variation in physician practice pattern: an examination of technical and cost efficiency for treating sinusitis

OBJECTIVE

An examination of the physician efficiency and resulting cost patterns by region.

DATA SOURCES

Virginia Medicaid sinusitis related claims for 1993 were aggregated to physician level (n = 178), and Area Resources File for 1993 was used to identify regions for evaluation.

STUDY DESIGN

The best practice performance in the usage of five resources (i.e., primary care physician visits, referral services, emergency room visits, prescriptions, laboratory tests) was identified using Data Envelopment Analysis (DEA). Five regions in Virginia were identified according to regional planning to evaluate the variation in efficiency across these regions.

PRINCIPAL FINDINGS

Inefficient physicians consumed significantly more resources and were 48% more costly than efficient physicians. Substantial regional variation was found and mainly attributed to the differences in use of prescriptions and laboratory procedures. Urban-rural discrepancy may explain part of the variation.

CONCLUSIONS

As this study reveals the existence of substantial variation in physician efficiency, actions should be taken to minimize the variation that is more affected by personal and structural factors. For example, information on efficient use of resources and corresponding patient outcomes can be disseminated to the attending physicians. Educational workshops can be conducted to allow sharing of experience between efficient and inefficient physicians. Efforts should also be directed to help inefficient physicians to adhere to practice guidelines.

Multinuclear solid-state three-dimensional MRI of bone and synthetic calcium phosphates

Multinuclear three-dimensional solid-state MRI of bone, tooth, and synthetic calcium phosphates is demonstrated in vitro and in vivo with a projection reconstruction technique based on acquisition of free induction decays in the presence of fixed amplitude magnetic field gradients. Phosphorus-31 solid-state MRI provides direct images of the calcium phosphate constituents of bone substance and is a quantitative measurement of the true volumetric bone mineral density of the bone. Proton solid-state MRI shows the density of bone matrix including its organic constituents, which consist principally of collagen. These solid-state MRI methods promise to yield a biological picture of bone richer in information concerning the bone composition and short range-crystalline order than the fluid-state images provided by conventional proton MRI or the density images produced by radiologic imaging techniques. Three-dimensional solid-state projection reconstruction MRI should be readily adaptable to both human clinical use and nonmedical applications for a variety of solids in materials science.

Stereotactic transcranial magnetic stimulation: correlation with direct electrical cortical stimulation

OBJECTIVE

To evaluate stereotactic transcranial magnetic stimulation (TMS) as a tool for presurgical functional mapping of human motor cortex.

METHODS

Transcranial magnetic stimulation using a frameless stereotactic system was performed in two patients with tumors near the central sulcus. TMS motor function maps were plotted on the patients' three-dimensional volumetric magnetic resonance imaging data and compared with direct electrical cortical stimulation at surgery with the patient under local anesthesia.

RESULTS

Stereotactic TMS was well tolerated by both patients and was consistent with known somatotopic representation of human motor cortex. The results demonstrated a good correlation between the TMS and electrical cortical stimulation maps, with all TMS responses eliciting more than 75% of the maximum motor evoked potential falling within 1 cm of the electrical cortical stimulation site.

CONCLUSIONS

Our findings indicate that stereotactic TMS is feasible and can provide accurate noninvasive localization of cortical motor function. It may prove to be a useful method for presurgical planning.

Assessing the impact of patient characteristics and process performance on rural intensive care unit hospital mortality rates

OBJECTIVE

To examine the relationship between patient characteristics, processes of care, and risk of hospital mortality in rural intensive care units (ICU).

DESIGN

Retrospective data analysis of ICU patients admitted to 19 rural Iowa hospitals between 1992 and 1994.

SETTING

ICUs in rural Iowa hospitals.

PATIENTS

ICU patients treated on mechanical ventilators meeting eligibility criteria.

MEASUREMENTS AND MAIN RESULTS

Patient age (odds ratio = 1.03, p < .01), a higher Acute Physiology and Chronic Health Evaluation II score (odds ratio = 1.06, p < .01), and a longer pre-ICU length of stay (odds ratio = 1.14, p < .05) were associated with a higher risk of death. Seven processes of care were examined (i.e., laboratory work, nursing assessment, stress ulcer protection, immobilization protection, nutritional management, ventilator management, and weaning). Considerable variation was observed between hospitals in performance of processes of care. Controlling for patient characteristics, better performance in ulcer protection (odds ratio = 0.1, p < .05) and ventilator management (odds ratio = 0.03, p < .05) were related to lower risk of mortality. A model incorporating both patient characteristics and processes of care achieved higher predictive accuracy than a model containing only patient characteristics (area under the receiver operating characteristic curve: 0.80 vs. 0.70, p < .01).

CONCLUSIONS

Most of the variation in mortality was explained by differences in patient physiologic and demographic characteristics at ICU admission. After adjusting for patient characteristics, better performance in some processes of care would have significant impact on reducing risk of mortality.

Functional magnetic resonance imaging and transcranial magnetic stimulation: complementary approaches in the evaluation of cortical motor function

Functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS) represent different approaches to mapping the motor cortex. fMRI identifies areas of hemodynamic changes during task performance while TMS provides electrophysiologic data concerning the localization and density of cortical motoneurons. Here we define the spatial correlation between fMRI and TMS maps and compared them with direct electrical cortical stimulation (ECS). We performed fMRI at 1.5 T on 3 normal subjects and 2 patients with mass lesions near the central sulcus using a multislice, asymmetric, spin-echo, echo-planar pulse sequence during the performance of a motor task. We also performed focal TMS with surface EMG recordings from the muscles primarily involved in the fMRI task. We coregistered the stimulation sites in real time with the fMRI maps using a frameless stereotactic system. In both patients we also performed ECS of the cortex during surgery under local anesthesia. fMRI maps were validated by the electrophysiologic data both pre- and intraoperatively. Our results suggest that regions of fMRI activation correspond spatially to areas of highest motoneuron density as demonstrated by electrophysiologic techniques.

Monoclonal antibody LR-1 recognizes murine heat-stable antigen, a marker of antigen-presenting cells and developing hematopoietic cells

The rat monoclonal antibody LR-1 was initially described to be reactive with an antigen present on murine splenic B lymphocytes. However, flow-cytometric analyses of cells obtained from thymus, bone marrow, spleen, and lymph nodes showed that LR-1 stained approximately 95, 95, 60-70 and 20% of cells present within these tissues in normal DBA/2 mice. The marker recognized by LR-1 was present on peripheral erythrocytes and splenic dendritic cells, and activation with lipopolysaccharide A further increased expression of this antigen by splenic B cells. This particular tissue and cellular distribution was similar to that delineated with monoclonal antibodies reactive with heat-stable antigen (HSA). Duallabelling studies were conducted to compare the reactivity patterns of LR-1 and the HSA-reactive monoclonal antibody J11d and indicated that both antibodies recognized splenocytes bearing B cell (IgM) or erythroid (TER-119, CD71) but not T cell (CD4, CD8) markers. Splenocytes exposed to phosphoinostol-specific phospholipase C showed marked reduction in LR-1 binding, indicating that this antibody recognized a glycosylphosphatidylinositol-anchored cell surface protein, consistent with the known structure of HSA. Mixing of LR-1 with the HSA-specific antibodies J11d or M1/69 provided flow-cytometric profiles indistinguishable from those obtained with either antibody alone. However, LR-1 inhibited M1/69 binding to splenocytes by 83%, while J11d reduced M1/69 binding to these cells by only 18%. This finding suggested that LR-1 and M1/69 recognize identical splenic HSA epitopes, while LR-1 and J11d bind distinct antigenic determinants of spleen HSA. Western blot analysis of splenocyte, thymocyte, bone marrow cell and erythrocyte detergent extracts revealed that LR-1 reacted with glycoforms of HSA of known molecular weights (30-55 kD). Thus, LR-1 recognizes HSA, the murine analogue of human CD24, and will be a useful reagent with which to investigate the role of HSA in the immune response and hematopoiesis.

B cell mitogenic activity of Toxocara canis adult worm antigen

The effect of Toxocara (T.) canis antigen (TcAg) on lymphocytes was studied in vitro using normal murine spleen cells and human peripheral blood lymphocytes. TcAg prepared from adult worms stimulated murine spleen cells to proliferate at concentrations of 1-125 micrograms/ml. The responder cells TcAg are B cells, because the response was depleted by the treatment of spleen cells with anti-immunoglobulin (Ig) antibody and complement and after separation on a nylon wool column. This response was not due to the contamination of lipopolysaccharide (LPS), because TcAg could stimulate C3H/HeJ spleen cells which are low responders to LPS. Not only the proliferative response but also polyclonal IgG and IgE production were stimulated with TcAg. TcAg also stimulated macrophages to produce interleukin-1 and could stimulate human B cells. These results suggest that TcAg is a potent B cell mitogen and this activity may be relevant to the alteration of immunological functions in hosts infected with T. canis.

Sensitivity of activated murine peritoneal macrophages to photodynamic killing with benzoporphyrin derivative

This study compared the ability of highly purified resting and activated DBA/2 mouse peritoneal macrophages to survive treatment with the photosensitizer benzoporphyrin derivative (BPD, verteporfin) and light. Culture of macrophages with recombinant murine interferon-gamma (rIFN-gamma, 100 U/mL) for 72 h imparted a phenotypic and functional activation by dramatically increasing cell surface expression of major histocompatibility complex Class II (Ia) molecules and the formation of nitric oxide. The rIFN-gamma-activated macrophages were significantly (P < 0.05) more sensitive (lethal dose to cause a 50% reduction in cell survival, LD50 = 14.4 +/- 1.1 ng/mL) to photodynamic killing with BPD and light (10 J/cm2) than cells (LD50 = 18.2 +/- 2.0 ng/mL) cultured in medium alone. In contrast, macrophages treated with different concentrations of bacterial lipopolysaccharide (LPS) were as resistant or more resistant to photodynamic killing than cells cultured in medium alone. No cytotoxic effect of BPD was detected in cultures containing the drug but protected from light. Comparable amounts of BPD were taken up in vitro by unactivated and rIFN-gamma-activated macrophages, as detected by flow cytometric analysis. However, cells cultured with LPS (10 micrograms/mL) took up more BPD than macrophages cultured in medium alone or with rIFN-gamma. The DBA/2 P815 mastocytoma cells took up greater amounts of the drug and were subsequently more vulnerable to treatment with BPD and light (LD50 = 6.9 ng/mL) than macrophages cultured under any condition. The explanation for the increased vulnerability of rIFN-gamma-activated macrophages and the greater resistance of LPS-activated macrophages, relative to medium-cultured macrophages, to photodynamic killing with BPD is uncertain.(ABSTRACT TRUNCATED AT 250 WORDS)

Functional magnetic resonance imaging for cortical mapping in pediatric neurosurgery

Currently there is considerable interest in applying functional imaging modalities to the problem of cortical localization. We present the case of a 15-year-old boy with a seizure disorder related to a tumor in the dominant supplementary motor area. This case illustrates the usefulness of functional magnetic resonance imaging as a new imaging tool for localization of cortical function in younger patients. The functional magnetic resonance imaging provided an anatomically accurate topographic map of operative site and subcortical structures along with relevant functional cortex. This information was useful for both presurgical planning and intraoperative localization. Validation of the technique in this instance was confirmed with intraoperative cortical motor mapping and the postoperative result.

Studies of human cord blood dendritic cells: evidence for functional immaturity

We have isolated low-density, nonadherent, nonphagocytic, HLA-DR+ve cells with the morphology of dendritic cells (DCs) from the cord blood of full-term newborn infants. Relative to adult DCs, cord blood DCs were poor stimulators of the mixed leukocyte reaction when either adult or cord blood mononuclear cells (MNCs) or T lymphocytes were used as responder cells. In contrast, cord blood T cells and MNCs responded normally to allogeneic adult DCs. Cord blood DCs performed poorly as accessory cells for T-lymphocyte mitogenic responses at suboptimal concentrations of concanavalin A (Con A) and phytohemagglutinin A or at optimal concentrations of mitogen and low numbers of DCs. Addition of recombinant interleukin-2 (rIL-2) or recombinant interferon-gamma (rIFN-gamma) to cord blood DC-T-cell cultures containing a suboptimal concentration of Con A potentiated the proliferative response. In contrast, rIL-2 and rIFN-gamma exerted little effect on the proliferative response of adult T cells cultured with Con A and DCs. Flow cytometric studies showed that levels of intercellular adhesion molecule-1 (ICAM-1; CD54) and major histocompatibility complex (MHC) class I HLA-ABC and class II HLA-DR antigens on cord blood DCs were significantly lower than those on adult blood DCs. These findings suggest that the relative inefficiency of cord blood DCs in the activation of T cells may be related to their low cell surface expression of MHC and cell adhesion molecules. The demonstrated impairment of cord blood DC function could be of importance in understanding the immunologic relationship between the fetus and mother and could contribute to the susceptibility of newborns to infection.