29 research outputs found
Late pulmonary metastases of renal cell carcinoma immediately after post-transplantation immunosuppressive treatment: a case report
Introduction
We report a case of pulmonary metastatic recurrence of renal adenocarcinoma soon after radical nephrectomy that was followed by renal transplant and immunosuppressive medication. Increased risk of metastatic recurrence of renal cell carcinoma should be considered in the immediate post-transplant period when immunosuppressive medication is administered, even if nephrectomy had been performed many years earlier.Case presentation
In 1986 the patient demonstrated renal insufficiency secondary to mesangial glomerulonephritis. In 1992 he underwent left side radical nephrectomy with histopathological diagnosis of clear cell adenocarcinoma. Mesangial glomerulonephritis in the remaining right kidney progressed to end-stage renal failure. In October 2000 he received a kidney transplant from a cadaver and commenced immunosuppressive medication. Two months later, several nodules were found in his lungs, which were identified as metastases from the primary renal tumor that had been removed with the diseased kidney 8 years earlier.Conclusion
Recurrence of renal cell carcinoma metastases points to tumor dormancy and reflects a misbalance between effective tumor immune surveillance and immune escape. This case demonstrates that a state of tumor dormancy can be interrupted soon after administration of immunosuppressant medication.This work was partially supported by the Fondo de Investigaciones Sanitarias (PI 02/0175), the plan Andaluz de Investigacion, and the Instituto de Salud Carlos III-Red de centros de Cancer, Spain
Morphological and hematological studies of Trypanosoma spp. infecting ornamental armored catfish from Guamá River-PA, Brazil
New way for iron introduction in LDH matrix used as catalysts for Friedel–Crafts reactions
The alkylation of toluene, reaction employing benzyl chloride as the alkylating agent over basic hydrotalcite materials: Fe–Mg–Al-LDH prepared by different synthesis methods, including the method of co-precipitation, impregnation and a new method called the method of intercalation by anion exchange in the lamellar space of the host structure LDH. Our prepared solids were characterized by chemical analysis, XRD analysis, BET method and thermogravimetric analysis (TGA) and tested in the alkylation of toluene by benzyl chloride reaction. Fe–Mg–Al-LDH clay without or with calcination (at 773 K) has been investigated. The catalyst derived from the hydrotalcite by its calcination at 773 K shows high catalytic activity for the alkylation of toluene and other aromatic compounds. The catalytically active species present in the catalyst in its most active form are the oxides of iron on the catalyst surface
Study of Methane Decomposition on Fe/MgO-Based Catalyst Modified by Ni, Co, and Mn Additives
In Situ Regeneration of Alumina-Supported Cobalt–Iron Catalysts for Hydrogen Production by Catalytic Methane Decomposition
A novel approach to the in situ regeneration of a spent alumina-supported cobalt⁻iron catalyst for catalytic methane decomposition is reported in this work. The spent catalyst was obtained after testing fresh catalyst in catalytic methane decomposition reaction during 90 min. The regeneration evaluated the effect of forced periodic cycling; the cycles of regeneration were performed in situ at 700 °C under diluted O2 gasifying agent (10% O2/N2), followed by inert treatment under N2. The obtained regenerated catalysts at different cycles were tested again in catalytic methane decomposition reaction. Fresh, spent, and spent/regenerated materials were characterized using X-ray powder diffraction (XRD), transmission electron microscopy (TEM), laser Raman spectroscopy (LRS), N2-physisorption, H2-temperature programmed reduction (H2-TPR), thermogravimetric analysis (TGA), and atomic absorption spectroscopy (AAS). The comparison of transmission electron microscope and X-ray powder diffraction characterizations of spent and spent/regenerated catalysts showed the formation of a significant amount of carbon on the surface with a densification of catalyst particles after each catalytic methane decomposition reaction preceded by regeneration. The activity results confirm that the methane decomposition after regeneration cycles leads to a permanent deactivation of catalysts certainly provoked by the coke deposition. Indeed, it is likely that some active iron sites cannot be regenerated totally despite the forced periodic cycling
Early Gastric Post-Transplant Lymphoproliferative Disorder and H pylori Detection after Kidney Transplantation: A Case Report and Review of the Literature
The incidence of post-transplantation lymphoproliferative disorder (PTLD) in the adult renal transplant population ranges from 0.7% to 4%. The majority of cases involve a single site and arise, on average, seven months after transplantation. Histopathology usually reveals B-cell proliferative disease and has been standardized into its own classification. Treatment modalities consist of decreased immunosuppression, eradication of Epstein-Barr virus, surgical resection, systemic chemotherapy and monoclonal antibody therapy; however, mortality remains high, typically with a short survival time. In patients who have undergone renal transplantation, approximately 10% of those with PTLDs present with gastrointestinal symptomatology and disease. Reported sites include the stomach, and small and large bowel. Very few cases of Helicobacter pylori or mucosal-associated lymphoid tissue have been described in association with PTLD. In the era of cyclosporine immunosuppression, the incidence of PTLD affecting the gastrointestinal tract may be increasing in comparison with the incidence seen with the use of older immunosuppression regimens. A case of antral PTLD and H pylori infection occurring three months after renal transplantation is presented, and the natural history and management of gastric PTLD are reviewed
Catalytic properties of Rh, Ni, Pd and Ce supported on Al-pillared montmorillonites in dry reforming of methane
International audienc
Термодинамічне дослідження портландцементу, що містить багатостінні вуглецеві нанотрубки
Мета даної роботи полягала в термодинамічному дослідженні властивостей потрландцементу, що
містить багатошарові вуглецеві нанотрубки. Вимірювання коефіцієнта теплового розширення двох чистих зразків і його нанокомпозиту мають однакову форму. Дилатометричні криві містять однакову кількість аномалій. Їх інтенсивність у різних зразків відрізняється. Калориметричне дослідження показує
подібний характер між кривими цифрового сигнального контролера (DSC) двох зразків, матриці та її
нанокомпозиту. Термогравіметрія двох матеріалів показує наявність кількох аномалій, ймовірно,
пов’язаних із явищем дегідратації. Впровадження багатошарових вуглецевих нанотрубок в цемент зробило нанокомпозит стабільним у широкому діапазоні температур порівняно з цементною матрицею.The objective of this work is the thermodynamic study of portland cement containing multi-walled carbon nanotubes. The measurements of the thermal expansion coefficient of the two pure samples and its
nanocomposite have the same shape. The dilatometric curves contain the same number of abnormalities.
Their intensity differs from sample to sample. The calorimetric study reveals a similar character between
the DSC curves of the two samples, the matrix and its nanocomposite. The thermogravimetry of the two
materials shows the presence of several anomalies probably linked to the phenomena of dehydration. The
insertion of the multi-walled carbon nanotubes into the cement made the nanocomposite stable over a wide
temperature range compared to the cement matrix
Sintering and dielectric properties of a technical porcelain prepared from economical natural raw materials
Abstract In this study, the production of a technical porcelain, for the ceramic dielectric applications by using economical natural raw materials, was investigated. The basic porcelain composition was selected consisting of 30 wt% kaolin, 45 wt% potash-feldspar and 25 wt% quartz. The obtained phases in the sintered samples were investigated by X-ray diffraction, Fourier transform infrared spectroscopy analysis, and scanning electron microscopy images. It has been confirmed by these techniques that the main crystalline phases were quartz and mullite. Dielectric measurements of technical porcelains have been carried out at 1 kHz from room temperature to 200 °C. The dielectric constant, loss factor, dielectric loss tangent, and resistivity of the porcelain sample sintered at 1160 °C were 22-25, 0.32-1.80, 0.006-0.07, and 0.2-9 x 1013 Ω.cm, respectively. The value of dielectric constant was significantly high when compared to that of conventional porcelains which did not exceed generally 9