122 research outputs found
Complete Clearance of Resistant Granuloma Faciale With Pulsed Dye Laser After Pre-treatment With Mometasone and Tacrolimus
Introduction: Granuloma faciale is an uncommon inflammatory dermatosis which usually affects the face and is often resistant to treatment.Case Report: A 39-year-old English lady with Fitzpatrick skin phototype II presented with typical lesions of granuloma faciale, confirmed on biopsy, on her cheeks and nose. Treatment with ScleroPlus pulsed dye laser (Candela Corporation, Wayland, Mass) produced no visible improvement. The patient re-presented 5 years later with the same lesions, now more prominent. No improvement was noted with topical mometasone, however addition of topical tacrolimus caused significant flattening. Since the erythema and telangiectases persisted, treatment with ScleroPlus pulsed dye laser was re-attempted. Treatments were performed with a wavelength of 595 nm, pulse duration of 1.5 ms and 7 mm spot at a fluence of 8.5 J/cm2 in the first session and 9.5 J/cm2 in the subsequent 2 sessions. This resulted in complete resolution without scarring or pigmentary change. There was no recurrence at follow-up one year later.Conclusion: Our observation supports the use of combination therapy in resistant cases of granuloma faciale. One such combination would be the application of a topical corticosteroid and tacrolimus followed by pulsed dye laser
Anatomy, Biology and Concepts, Pertaining to Lung Cancer Stage Classification
AbstractThe proposed lung cancer stage classification system remains grounded in anatomic characteristics, although the large patient database contributing to this revision has dramatically expanded our body of knowledge. Predictably this has led to increased complexity due to the identification of an increasing number of subpopulations of patients. Patterns of clinical presentation characterizing these subgroups may provide clues about the propensity of tumors within a subgroup toward a particular pattern of biologic behavior. This article explores concepts regarding tumor biology that can be applied to the anatomically based new staging system
The Effect of Fe-Al Substitution on the Crystal Structure of MgSiO3 Bridgmanite
The crystal chemistry of ten well-characterized bridgmanite single-crystals with Fe and Al contents ranging from 0 to 0.40 atoms per two-cation formula units were investigated by single-crystal X-ray diffraction. Structural refinements indicate that Fe3+ and Al mainly occupy the Mg and Si sites, respectively, when present in similar proportions. Molar volumes of bridgmanite endmember components were refined using data from this and previous studies and found to decrease in the order Fe3+Fe3+O3 > MgFe3+O2.5 > Fe3+AlO3 > MgAlO2.5 > AlAlO3 > Fe2+SiO3 > MgSiO3. Fe3+AlO3 charge-coupled substitution leads to an anisotropic increase of B-O bond distances, resulting in more distorted octahedral B sites and in a more significant increase of the c-axis with respect to the a- and b-axes. Valence bond calculations indicate that the A site is more compressible than the B site for all bridgmanite samples studied, implying that octahedral tilting and distortion will dominate the bridgmanite compression mechanism. Guided by these crystal chemical observations, bulk moduli of bridgmanite endmember components were estimated using results of previous studies. The volume changes of equilibria controlling the speciation of bridgmanite components were then calculated at conditions relevant to the top of Earth's lower mantle. The proportion of oxygen vacancy components is predicted to decrease with pressure. While the stability of the bridgmanite Fe3+AlO3 component will drive charge disproportionation to produce iron metal at the top of the lower mantle, this appears to be much less favorable by 50 GPa. An increase in the proportion of the Fe3+Fe3+O3 bridgmanite component, however, may favor the formation of iron metal at higher pressures
Oxygen Vacancy Ordering in Aluminous Bridgmanite in the Earth's Lower Mantle
Oxygen vacancies (OVs), that charge-balance the replacement of octahedrally coordinated Si4+ by Al3+ in the mineral bridgmanite, will influence transport properties in the lower mantle but little is known about their stability and local structure. Using 27Al nuclear magnetic resonance (NMR) spectroscopy we have characterized OVs within six aluminous bridgmanite samples. In the resulting NMR spectra sixfold, fivefold, and fourfold coordinated Al species are resolved, in addition to near eightfold coordinated Al substituting for Mg. Fivefold coordinated Al is formed by single OV sites but fourfold coordination must result from short range ordering of OVs, producing OV clusters that may form through migration into twin domain walls. Characterizing the occurrence of such OV structures is an important prerequisite for understanding how transport properties change with depth and composition in the lower mantle
Lymphadenopathy after Initiating HAART in an HIV-positive Patient with Kaposi's Sarcoma: a Case of Multicentric Castleman's Disease
We present the case of a 33-year-old lady who was diagnosed with disseminated Kaposi’s sarcoma and HIV infection. The patient improved on highly active antiretroviral therapy (HAART), however, nine days into treatment, she became febrile and dyspnoeic and developed tender cervical and axillary lymphadenopathy. Despite treatment for suspected sepsis and immune reconstitution, she died in intensive care. Lymph node biopsies revealed coexistent Castleman’s disease and Kaposi’s sarcoma.
Initiation of HAART can be rarely associated with unmasking and rapid progression of Castleman’s disease, a phenomenon called immune reconstitution. Urgent investigation and treatment with agents such as steroids and cytotoxic drugs can be life-saving
Safety of meglumine gadoterate (Gd-DOTA)-enhanced MRI compared to unenhanced MRI in patients with chronic kidney disease (RESCUE study)
OBJECTIVE: To prospectively compare the renal safety of meglumine gadoterate (Gd-DOTA)-enhanced magnetic resonance imaging (MRI) to a control group (unenhanced MRI) in high-risk patients. METHODS: Patients with chronic kidney disease (CKD) scheduled for MRI procedures were screened. The primary endpoint was the percentage of patients with an elevation of serum creatinine levels, measured 72 ± 24 h after the MRI procedure, by at least 25 % or 44.2 μmol/l (0.5 mg/dl) from baseline. A non-inferiority margin of the between-group difference was set at −15 % for statistical analysis of the primary endpoint. Main secondary endpoints were the variation in serum creatinine and eGFR values between baseline and 72 ± 24 h after MRI and the percentage of patients with a decrease in eGFR of at least 25 % from baseline. Patients were screened for signs of nephrogenic systemic fibrosis (NSF) at 3-month follow-up. RESULTS: Among the 114 evaluable patients, one (1.4 %) in the Gd-DOTA-MRI group and none in the control group met the criteria of the primary endpoint [Δ = −1.4 %, 95%CI = (−7.9 %; 6.7 %)]. Non-inferiority was therefore demonstrated (P = 0.001). No clinically significant differences were observed between groups for the secondary endpoints. No serious safety events (including NSF) were noted. CONCLUSION: Meglumine gadoterate did not affect renal function and was a safe contrast agent in patients with CKD. KEY POINTS: • Contrast-induced nephropathy (CIN) is a potential problem following gadolinium administration for MRI. • Meglumine gadoterate (Gd-DOTA) appears safe, even in patients with chronic kidney disease. • Gd-DOTA only caused a temporary creatinine level increase in 1/70 such patients. • No case or sign of NSF was detected at 3-month follow-up
Water Defluoridation: Nanofiltration vs Membrane Distillation
Nowadays, fluoride contamination of drinking water is a major problem for various countries, because high concentrations of fluoride pose a risk of dental and skeletal fluorosis. Over past years, membrane nanofiltration (NF) has been proposed as convenient defluoridation technology. However, NF cannot be applied to water systems with high fluoride concentration, and the disposal of the membrane concentrate remains an issue. In this work, we compared a commercial polyester NF membrane and a polypropylene hollowfiber membrane distillation (MD) module for their ability to remove fluoride ions from water in the presence of hardness ions and organic fouling agents. The NF membrane can offer more than 10 times higher water productivity than MD, under realistic gradients of temperature and pressure, respectively. Despite that, after reaching a concentration factor of about 3, fouling and scaling caused the flux to drop to about 80% with respect to its initial value. Moreover, F− retention decreased from 90% to below 80%, thus providing a permeate of scarce quality. MD was operated in the direct-contact mode on a polypropylene hollowfiber membrane, which was charged with a hot feed flow (average T = 58 °C) on one side and a cooled (20 °C) permeate flow of distilled water on the other side. The concentration of fluoride ions in the permeate was always below the detection limit of our electrode (0.2 ppm), regardless of the fluoride concentration in the feed. Moreover, the MD module showed higher resistance to fouling and scaling than NF, and CaF2 crystals were recovered from the MD concentrate after cooling. These results suggest that the synergic combination of the two techniques might be beneficial for the purification of fluoridecontaminated water systems: MD can be used to further concentrate the NF retentate, thus producing high-purity water and recovering CaF2 crystals.Instituto de Investigaciones FisicoquÃmicas Teóricas y Aplicada
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Survival Among Patients With High-Risk Gastrointestinal Cancers During the COVID-19 Pandemic
Importance: Prior reports demonstrated that patients with cancer experienced worse outcomes from pandemic-related stressors and COVID-19 infection. Patients with certain malignant neoplasms, such as high-risk gastrointestinal (HRGI) cancers, may have been particularly affected. Objective: To evaluate disruptions in care and outcomes among patients with HRGI cancers during the COVID-19 pandemic, assessing for signs of long-term changes in populations and survival. Design, Setting, and Participants: This retrospective cohort study used data from the National Cancer Database to identify patients with HRGI cancer (esophageal, gastric, primary liver, or pancreatic) diagnosed between January 1, 2018, and December 31, 2020. Data were analyzed between August 23 and September 4, 2023. Main Outcome and Measures: Trends in monthly new cases and proportions by stage in 2020 were compared with the prior 2 years. Kaplan-Meier curves and Cox regression were used to assess 1-year mortality in 2020 compared with 2018 to 2019. Proportional monthly trends and multivariable logistic regression were used to evaluate 30-day and 90-day mortality in 2020 compared with prior years. Results: Of the 156 937 patients included in this study, 54 994 (35.0%) were aged 60 to 69 years and 100 050 (63.8%) were men. There was a substantial decrease in newly diagnosed HRGI cancers in March to May 2020, which returned to prepandemic levels by July 2020. For stage, there was a proportional decrease in the diagnosis of stage I (−3.9%) and stage II (−2.3%) disease, with an increase in stage IV disease (7.1%) during the early months of the pandemic. Despite a slight decrease in 1-year survival rates in 2020 (50.7% in 2018 and 2019 vs 47.4% in 2020), survival curves remained unchanged between years (all P > .05). After adjusting for confounders, diagnosis in 2020 was not associated with increased 1-year mortality compared with 2018 to 2019 (hazard ratio, 0.99; 95% CI, 0.97-1.01). The rates of 30-day (2.1% in 2018, 2.0% in 2019, and 2.1% in 2020) and 90-day (4.3% in 2018, 4.4% in 2019, and 4.6% in 2020) operative mortality also remained similar. Conclusions and Relevance: In this retrospective cohort study, a period of underdiagnosis and increase in stage IV disease was observed for HRGI cancers during the pandemic; however, there was no change in 1-year survival or operative mortality. These results demonstrate the risks associated with gaps in care and the tremendous efforts of the cancer community to ensure quality care delivery during the pandemic. Future research should investigate long-term survival changes among all cancer types as additional follow-up data are accrued.</p
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