[Comparison of extracorporeal membrane oxygenation applicated in critical patients with COVID-19 and novel influenza A (H1N1) virus pneumonia].

Objective: To compare the clinical characteristics and prognosis of critical patients with COVID-19 and novel influenza A (H1N1) virus pneumonia (influenza pneumonia) applied with extracorporeal membrane oxygenation (ECMO). Methods: A total of 24 patients with influenza pneumonia treated with ECMO in respiratory intensive-care unit (ICU) of Beijing Chaoyang Hospital from March 2016 to December 2019 and 12 patients with COVID-19 hospitalized from February 1, 2020 to March 31, 2020 in 5 government designated infectious hospitals of Beijing and Hebei Province that applied with ECMO were enrolled. The demographic data, clinical manifestations, and ECMO related information were described and analyzed and all numerical variables are described as M (P25, P75). Results: The age of COVID-19 patients was 77 (66, 79) years old, which was older than influenza pneumonia patients [46 (32, 62) years old], P<0.05; acute lung injury score and respiratory ECMO survival prediction (RESP) score before ECMO application were 3.3 (3.0, 3.5) and 1 (0, 2), respectively, which were lower than influenza pneumonia patients [3.8 (3.5, 4.0) and 4 (2, 6), respectively], all P values<0.05. Thrombotic complications, bleeding complications, and ventilator-associated pneumonia occurred in ECMO applied COVID-19 patients were 4, 10 and 5 cases, respectively, which were more than that among influenza pneumonia patients (1, 9, and 2 cases, respectively), all P values<0.05. The length of ICU stay of COVID-19 patients was 31 (28, 75) d, which was longer than that of influenza pneumonia patients [27 (18, 39) d], P<0.05. The cases with successful decannulation of ECMO among COVID-19 and influenza pneumonia patients were 6 and 14 cases, respectively and mortality during ICU stay were 8 cases and 11 cases, respectively, and the difference were not statistically significant (all P values>0.05). Conclusion: COVID-19 patients applied with ECMO have more ECMO-related complications and a longer stay in the ICU than patients with influenza pneumonia.

Bridging classical and quantum mechanics.

Using a watt balance and a frequency comb, a mass-energy equivalence is derived. The watt balance compares mechanical power measured in terms of the meter, the second, and the kilogram to electrical power measured in terms of the volt and the ohm. A direct link between mechanical action and the Planck constant is established by the practical realization of the electrical units derived from the Josephson and the quantum Hall effects. By using frequency combs to measure velocities and acceleration of gravity, the unit of mass can be realized from a set of three defining constants: the Planck constant h, the speed of light c, and the hyperfine splitting frequency of 133Cs.

Invited Article: A precise instrument to determine the Planck constant, and the future kilogram.

A precise instrument, called a watt balance, compares mechanical power measured in terms of the meter, the second, and the kilogram to electrical power measured in terms of the volt and the ohm. A direct link between mechanical action and the Planck constant is established by the practical realization of the electrical units derived from the Josephson and the quantum Hall effects. We describe in this paper the fourth-generation watt balance at the National Institute of Standards and Technology (NIST), and report our initial determination of the Planck constant obtained from data taken in late 2015 and the beginning of 2016. A comprehensive analysis of the data and the associated uncertainties led to the SI value of the Planck constant, h = 6.626 069 83(22) × 10(-34) J s. The relative standard uncertainty associated with this result is 34 × 10(-9).

[Wild-type p53 stimulates vincristine-induced apoptosis].

Recent studies indicate that wild-type p53 can trigger cell apoptosis induced by many chemotherapeutic agents which induce DNA damage or cause disruptions of DNA metabolism, such as ADM, 5-FU, VP-16 and radiation. We introduced the wild-type p53 gene into a MDR cell line KBV200 in which the endogenous p53 was found to be rearranged. By G418 selection and Northern blot analysis, a G418-resistant clone named KBV200-p53 was obtained which continuously expressed the exogenous wild-type p53 mRNA. After treatment with Vincristine(VCR), the wild type p53-expression cells presented typical morphology characteristic of apoptosis analysed under electron and fluorescence microscopes. Flow cytometer analysis showed that the KBV200-p53 cells were more readily undergo apoptosis than their parental cells KBV200. After treatment with VCR 600 nmol.L-1 for 24 h, the apoptotic percentage of KBV200-p53 and KBV200 cells was about 42.4% and 8.4%, respectively. This result indicates that wild-type p53 stimulates VCR-induced apoptosis in KBV200 cells.

Influence of fish on the bioavailability of plant iron in the anemic rat.

The effect of fish protein and fish oil on the utilization of endogenous iron in wheat bran, spinach and soy protein isolate was investigated by using the anemic rat as an animal model. Marine products were substituted for casein and corn oil in the diets of these animals. Hemoglobin regeneration was one criteria used to measure iron uptake. Relative biological values (RBV) were computed from a regression equation obtained from control animals receiving graded levels of FeSO4 X 7H2O. The RBV of iron from plant sources provided in diets containing casein-corn oil versus fish-fish oil were: wheat bran, 123 vs. 111%; spinach, 53 vs. 49%; and soybean isolate, 84 vs. 67%; RBV FeSO4 = 100%. These changes were not significant. The decreases in iron absorption from diets containing marine products was attributed to the fish oil. Absorption of exogenous iron (59Fe) was measured in the same animals after the 14-day repletion period. Assimilation of the 59Fe was highly correlated (r2 = 0.958) with hemoglobin level at time of dosing. Diet composition did not appear to have the same effect on the percentage of 59Fe retained after 110 hours by the rat as compared to levels of hemoglobin regeneration (i.e., RBV). A "meat factor" effect was not shown by substituting fish for casein the diets containing plant iron sources fed anemic rats.

Relationship of components in wheat bran and spinach to iron bioavailability in the anemic rat.

Components found in wheat bran and spinach were evaluated as to their affect on the bioavailability of ferrous iron (i.e., FeSO4) by using the criteria of hemoglobin regeneration in anemic rats. The relative biological value (RBV) of iron in wheat bran and spinach (FeSO4 = 100%) were determined to be 124 and 53%, respectively. Control diets with graded levels of FeSO4 did not contain dietary fiber (i.e., cellulose). Adding cellulose (1.74%) or phytic acid (0.66%) at levels contained in the wheat bran diet, significantly increased (P less than 0.05) the RBV f the ferrous iron to 126 and 124%, respectively. The addition of 2.10% oxalic acid, the amount in the spinach diet, caused the highest increase in RBV to 164%. Combining these dietary components, plus lignin (0.67%) and pectin (0.63%), in various combinations, resulted in RBVs equivalent or significantly higher than 100%. The bioavailability of iron in plant foods appears to be dependent on how this nutrient is presented to the mucosa. Cellulose, phytate or oxalate added to a purified diet containing ferrous iron significantly enhanced the bioavailability of this element. Relative biological values for iron were also calculated based on food intake and growth rate. The latter parameters are believed to have greater utility in determining RBV when food intake and/or growth rate may vary among animals consuming different sources of test iron.

[Evaluation of a self-prepared enzyme immunoassay kit for detection of alpha-fetoprotein].

A "sandwich" technique of enzyme immunoassay (EIA) kit for human alpha-fetoprotein has been developed by using commercially available reagents. The assay range is 0.5-60 ng/ml. Within-run coefficients of variation (C.V.) for 20 determination at three different concentrations were 4.4-10.3%, and between-run C.V. were 4.9-10.8%. The sensitivity and specificity of the kit has been compared with those of two commercially available kits (Abbott and Roche r1 = 0.991, r2 = 0.989.) This kit has some advantages over currently available kits. The assay is incubated in room temperature, no waterbath is required. The solid phase is dry store, it have long shelf life. The kit is inexpensive to operate, and it is suitable for any laboratory.

Desmoplastic amelanotic melanoma of palate: a case report with immunohistochemistry and electron microscopic studies.

A 24 year-old male with painful swelling over the right side of his palate for about two weeks was presented. An incisional biopsy was performed. In a routine hematoxylin and eosin examination by light microscopy, spindle and epithelioid cells with a bizarre appearance were discernible in the submucosal area. A pagetoid pattern was found in areas of the epithelium. Since this is not a remarkable finding, further examinations, such as the Trichrome-Masson and silver stain, immunohistochemistry using cytokeratin, vimentin, S-100, leukocyte common antigen, factor VIII, and alpha-1-antichymotrypsin detection kits, and electron microscopy were all carried out. According to the histological pattern of cells and the positive findings from the special stains, immunohistochemistry, and electron microscopy, a diagnosis of desmoplastic amelanotic melanoma was made. This variant of melanoma is a rare disorder with unremarkable, non-specific clinical manifestations in the oral cavity, which makes the diagnosis of this disease more difficult. We, therefore, report one case of this disease. Owing to the fact that diagnosis of this variant was mainly based on the positive findings of vimentin and S-100 in the immunohistochemistry examination and intracellular premelanosome detected by electron microscopy, immunodiagnosis and electron microscopy seem to be essential for differential diagnosis.

Image display for collision avoidance of radiation therapy: treatment planning.

Patient treatment in a medical linear accelerator is characterized by many angular and translational movements of the gantry and couch. The direction and orientation of each treatment beam is specified by a set of gantry, turntable, and collimator angles. It is possible that some selected treatment field configurations will result in gantry/couch or gantry/patient collisions that remain undetected during the treatment planning process. In this work, a digital camera has been used to record all the workable gantry/ patient set-up images, and a Windows programming language is used to edit and display these images on a personal computer for the treatment planner to screen the treatment plans. These graphical displays enable the planner to be aware of any potential collision hazards by an actual visualization of each selected gantry/turntable or gantry/patient angle configuration.

Whole body radiation exposure with gamma unit radiosurgery.

BACKGROUND: Stereotactic radiosurgery is the use of external radiation in association with a stereotactic device to precisely locate and destroy inaccessible deep-seated lesions within the brain in a single treatment session. Very little attention has been paid to the extracranial sites of radiation exposure measurements. This study evaluates the extracranial absorbed dose due to leakage and scattered radiation of the Gamma Unit used in radiosurgery. METHODS: The absorbed doses were measured with thermoluminescent dosimetry (TLDs). Single and multiple Gamma Unit treatment with the 18mm collimator helmet was given and a Rando tissue equivalent phantom was in place to simulate a patient treatment. TLDs were placed on the phantom to measure the absorbed doses by the organs at risk. Two TLD chips were placed at each of the following organs: eye, thyroid, sternum and gonads. The irradiated TLDs were read with a Vinten TLD system 654D. The TLD factor was determined by irradiating TLDs with a cobalt-60 teletherapy unit of a known dose of radiation. RESULTS: The average maximum target absorbed dose was 30 Gy. The measured absorbed dose in selected organs from Gamma Unit radiosurgery with one or more isocenters was 21-53 cGy for the eye, 4-8 cGy for the thyroid, 3-4 cGy for the sternum and 2-3 cGy for the gonads. The dose to extracranial sites increased with the number of isocenters. The radiation dose to extracranial sites became much more substantial when multiple isocenters were used. CONCLUSIONS: The potential risk of radiation exposure is radiation induced tumors. No cases have been reported in patients treated with Gamma Unit radiosurgery. Given the benefit of Gamma Unit treatment, the clinical significance of these doses is minimal.