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1.
Polymers (Basel) ; 14(19)2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36235977

RESUMEN

Polymer electrolyte membrane (PEM) fuel cells have the potential to reduce our energy consumption, pollutant emissions, and dependence on fossil fuels. To achieve a wide range of commercial PEMs, many efforts have been made to create novel polymer-based materials that can transport protons under anhydrous conditions. In this study, cross-linked poly(vinyl) alcohol (PVA)/poly(ethylene) glycol (PEG) membranes with varying alumina (Al2O3) content were synthesized using the solvent solution method. Wide-angle X-ray diffraction (XRD), water uptake, ion exchange capacity (IEC), and proton conductivity were then used to characterize the membranes. XRD results showed that the concentration of Al2O3 affected the degree of crystallinity of the membranes, with 0.7 wt.% Al2O3 providing the lowest crystallinity. Water uptake was discovered to be dependent not only on the Al2O3 group concentration (SSA content) but also on SSA, which influenced the hole volume size in the membranes. The ionic conductivity measurements provided that the samples were increased by SSA to a high value (0.13 S/m) at 0.7 wt.% Al2O3. Furthermore, the ionic conductivity of polymers devoid of SSA tended to increase as the Al2O3 concentration increased. The positron annihilation lifetimes revealed that as the Al2O3 concentration increased, the hole volume content of the polymer without SSA also increased. However, it was densified with SSA for the membrane. According to the findings of the study, PVA/PEG/SSA/0.7 wt.% Al2O3 might be employed as a PEM with high proton conductivity for fuel cell applications.

2.
J Egypt Natl Canc Inst ; 33(1): 39, 2021 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-34905125

RESUMEN

BACKGROUND: Pathological complete response (pCR) is a surrogate for the efficacy of neoadjuvant chemotherapy (NCT) in locally advanced breast cancer (LABC). We analyzed the predictive clinical factors for pathological responses and survival outcomes in a cohort of Egyptian patients. METHODS: We evaluated the medical records of patients with breast cancer who received NCT in our academic institute. Survival curves were estimated with the Kaplan-Meier method. Cox proportional models were used for multiple regression analysis. RESULTS: Our cohort included 368 patients with a median age of 48 years (range 21-70). The median follow-up time was 3 years. The clinical tumor stage (T3-4) represented 58%, with 80% having positive axillary nodes. The luminal subgroup prevailed by 68%. The objective response rate (ORR) reached 78%, and 16% of patients achieved pCR. The clinical node stage and optimal chemotherapy were associated with higher ORR (p = 0.035 and p = 0.001, respectively). Predictors of pCR were clinical T-stage (p = 0.026), high Ki-67 index > 20 (p = 0.05), and receiving optimal chemotherapy (p = 0.014). The estimated 3-year disease free-survival (DFS) was 53%. Receptor status, achieving ORR, and pCR were associated with better DFS with hazard ratios of 0.56, p = 0.008; 0.38, p = 0.04; and 0.28, p = 0.007, respectively. CONCLUSIONS: Luminal tumors still draw benefit from neoadjuvant chemotherapy in terms of clinical response and breast conservative surgery. Treatment escalation to those who did not achieve pCR requires more investigation, given a higher recurrence rate in real-world experience.


Asunto(s)
Neoplasias de la Mama , Terapia Neoadyuvante , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Supervivencia sin Enfermedad , Femenino , Humanos , Mastectomía , Persona de Mediana Edad , Adulto Joven
3.
Am J Obstet Gynecol ; 204(5): 418.e1-418.e12, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21349490

RESUMEN

OBJECTIVE: Disorders that lead to preterm delivery influence the fetal inflammatory response. STUDY DESIGN: We calculated odds ratios of elevated concentrations of 25 blood proteins on the first postnatal day in 798 infants born before the 28th week and classified by the pregnancy disorder that lead to preterm delivery. RESULTS: Concentrations of cytokines (IL-1ß, IL-6, TNFα), cytokine receptors (IL-6R, TNF-R1, TNF-R2), systemic inflammatory proteins (CRP, SAA, MPO), chemokines (IL-8, MCP-1, MCP-4, MIP-1ß, RANTES, I-TAC), adhesion molecules (ICAM-1, ICAM-3, VCAM-1, E-selectin), and metalloproteinases (MMP-1, MMP-9) were elevated in children delivered after preterm labor, membrane rupture, abruption, and cervical insufficiency, whereas such a pattern was not seen after preeclampsia or fetal indication/growth restriction. Inflammatory profiles were also associated with maternal vaginitis. CONCLUSION: The patterns of blood proteins in the newborn support the division of pregnancy disorders that lead to preterm delivery into those associated, and those not associated, with inflammation.


Asunto(s)
Moléculas de Adhesión Celular/sangre , Quimiocinas/sangre , Citocinas/sangre , Rotura Prematura de Membranas Fetales/sangre , Metaloproteinasas de la Matriz/sangre , Trabajo de Parto Prematuro/sangre , Preeclampsia/sangre , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Embarazo
4.
Obstet Gynecol ; 102(2): 229-31, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12907093

RESUMEN

BACKGROUND: West Nile virus is an emerging pathogen in the United States. Although most cases are subclinical, serious infection can occur in the form of fulminant meningoencephalitis. CASE: We present a case of West Nile virus meningoencephalitis complicating pregnancy. The patient presented in the second trimester with fever, nuchal rigidity, and mental status changes. The diagnosis was made by demonstrating the presence of immunoglobulin M antibody to West Nile virus in the cerebrospinal fluid. Gradual clinical improvement was noted after several days of supportive care. No obvious fetal consequences of infection were noted after birth. CONCLUSION: Obstetricians and health care providers need to be mindful of West Nile virus infection in pregnant women presenting with fever and neurological signs, particularly in endemic areas.


Asunto(s)
Complicaciones Infecciosas del Embarazo/diagnóstico , Fiebre del Nilo Occidental/diagnóstico , Femenino , Humanos , Embarazo
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