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1.
Int J Surg Pathol ; 23(5): 359-63, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25838331

RESUMEN

Pseudocapsule in renal cell carcinoma (RCC) has been described but little is known about its prevalence and extent. Pseudocapsule was analyzed in 105 RCCs (44 clear cell, 44 chromophobe, 17 papillary). Pseudocapsule was graded as follows: grade 1, thickness comparable to adjacent muscular arteries; grade 2, thickness more than twice the diameter of adjacent muscular arteries; grade 3, grade 2 findings with vasculopathy. Tumor size, tumor regression, and International Society of Urologic Pathology (ISUP) nucleolar grade were recorded. Cases with grade 3 pseudocapsule were stained with elastic silver stain, Alcian blue, smooth muscle actin, and CD31. More clear cell RCCs had pseudocapsule (89%, 39/44) than chromophobe (30%, 13/44) and papillary (35%, 6/17). Average tumor size with pseudocapsule was 3.9 cm; average tumor size without pseudocapsule was 3.8 cm (P = .77). Grade 2 pseudocapsule was common in clear cell RCC (56%, 22/39). Chromophobe and papillary RCC had grade 1 pseudocapsule in 77% (10/13) and 83% (5/6) of cases. Grade 3 pseudocapsule was only seen in clear cell RCC (10%, 4/39). No correlation was noted between degenerative tumor changes, tumor size, ISUP nucleolar grade, and presence and grade of pseudocapsule. Smooth muscle actin and CD31 showed abundant smooth muscle component and rich vasculature within the pseudocapsule. Arterial elastic membrane disruption and/or fibrointimal mucin deposits were present in grade 3 pseudocapsule. Thus, pseudocapsule is rather characteristic and more prominent in clear cell, less frequent in chromophobe, and rare in papillary RCC. Its presence may be evaluated radiologically or in biopsy specimens with scant tumor fragments.


Asunto(s)
Carcinoma de Células Renales/patología , Neoplasias Renales/patología , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Renales/metabolismo , Humanos , Neoplasias Renales/metabolismo , Clasificación del Tumor , Estudios Retrospectivos
2.
Arch Pathol Lab Med ; 137(7): 955-60, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23808467

RESUMEN

CONTEXT: Breast cancer treatment has greatly evolved from radical mastectomy to more cosmetically acceptable and less-debilitating surgeries. Nipple-sparing mastectomy is increasingly done for both cancer treatment and risk reduction. The frequency of terminal duct lobular units (TDLUs) and occult neoplastic epithelial proliferation in grossly/clinically unremarkable nipples (GUNs) is not well investigated. OBJECTIVE: To describe frequency of TDLUs and occult and overt neoplastic nipple involvement. DESIGN: Nipples from 105 consecutive specimens (90 therapeutic, 15 prophylactic) were studied. Sixty-five nipples were entirely submitted to evaluate frequency of TDLUs; the rest had 1 vertical section submitted. RESULTS: Terminal duct lobular unit was seen in 17 GUNs (26%). Six had TDLU in the base, 6 had it in the papilla, and 5 in both. Four GUNs showed lobular carcinoma in situ (1), Paget disease (1), and pagetoid extension of underlying malignancy (2). Grossly/clinically abnormal nipples had Paget disease (2), lymphovascular invasion (2), invasive carcinoma (4), and pagetoid extension (5). Involved nipples were closer to tumor (mean, 1.1 versus 3.2 cm, P < .001), had larger underlying tumors (mean, 4.3 versus 2.6 cm, P = .03) and of higher grade (P = .04), and more often had lymph node metastases (91% versus 44%, P = .007). No pathologic abnormalities were found in prophylactic mastectomy nipples. CONCLUSIONS: Terminal duct lobular units were seen in 26% of nipples. They were frequently seen in the nipple papilla. Occult neoplastic epithelial proliferation was seen in 5% of grossly/clinically unremarkable therapeutic mastectomy nipples. Pagetoid extension was the dominant spread of underlying malignancy. Overall, the nipple was more often involved by larger and higher-grade tumors located closer to the nipple. All prophylactic mastectomies had unremarkable nipples. These findings should be considered while selecting patients for nipple-sparing mastectomy.


Asunto(s)
Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/patología , Carcinoma Lobular/secundario , Glándulas Mamarias Humanas/patología , Pezones/patología , Enfermedad de Paget Mamaria/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/cirugía , Carcinoma Intraductal no Infiltrante/cirugía , Carcinoma Lobular/cirugía , Femenino , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática , Glándulas Mamarias Humanas/cirugía , Mastectomía , Persona de Mediana Edad , Clasificación del Tumor , Pezones/cirugía , Enfermedad de Paget Mamaria/cirugía , Estudios Prospectivos
3.
Am J Surg Pathol ; 37(7): 1076-84, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23759933

RESUMEN

Mucinous mammary carcinoma (MC) is a tumor type with relatively favorable prognosis. Unlike the circumstances surrounding conventional invasive duct carcinoma, data are limited regarding precursor lesions for MC. This study characterizes patterns of mucinous ductal carcinoma in situ (DCIS) as a precursor lesion for MC. All slides from 130 cases of MC encountered between 2000 and 2011 at Henry Ford Hospital, Detroit, MI were reviewed to subclassify MC, identify DCIS, and explore transition patterns from DCIS to MC. Calponin, p63, chromogranin, synaptophysin, CD56, and MIB-1 immunostaining analyses were performed in 65 cases. Among 106 cases of pure (71 type A, 35 type B) and 24 cases of mixed MC, DCIS appeared in 88 (68%) specimens, with all but 4 showing luminal mucin accumulation. Dominant patterns of mucinous DCIS were cribriform/solid (66), cribriform and papillary (7), papillary (5), micropapillary (3), and flat (3). Fifty-seven (68%) cases of mucinous DCIS demonstrated transitions from DCIS to MC. Luminal mucinous distention, focal flattening and attenuation of the epithelium, and disruption of the duct wall resulting in a mucocele-like extravasation of malignant epithelia with escaping mucin was a transition pattern seen with all architectures of DCIS and in all types of MC. This was the only pattern of transition to type A MC. The epithelial outpouching, formation of a cleft with accumulation of mucin around the epithelium, and transition into mucin pools with floating tumor cell clusters was the second transition pattern that went from cribriform/solid DCIS to type B and mixed MC. DCIS preceding aggressive phenotypes of MC (type B and mixed) more often had a cribriform/solid architecture, higher nuclear grade, and higher Ki-67-labeling index (all P<0.05). In summary, mucinous DCIS is a precursor to MC with distinctive features that link patterns of DCIS with aggressive MC phenotypes. The 2 observed transitions between mucinous DCIS and MC suggest that pathogenesis of different types of MC is different correlating with less or more aggressive behavior of the latter.


Asunto(s)
Adenocarcinoma Mucinoso/patología , Neoplasias de la Mama Masculina/patología , Carcinoma Intraductal no Infiltrante/patología , Transformación Celular Neoplásica , Lesiones Precancerosas/patología , Adenocarcinoma Mucinoso/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama Masculina/metabolismo , Carcinoma Intraductal no Infiltrante/metabolismo , Femenino , Humanos , Antígeno Ki-67/metabolismo , Masculino , Persona de Mediana Edad , Mucinas/metabolismo , Lesiones Precancerosas/metabolismo
4.
Arch Pathol Lab Med ; 137(2): 251-4, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23368867

RESUMEN

CONTEXT: Clear cell renal cell carcinoma (CCRCC) has a rich, sinusoid-like vascularity frequently used as a diagnostic criterion. CCRCC with predominantly vascular architecture has not been described. OBJECTIVE: To describe 4 unusual CCRCC cases, primarily presenting with hemangioma-like morphologic pattern. DESIGN: Clinicopathologic and selected immunohistochemical analysis of 4 cases of CCRCC mimicking hemangioma. RESULTS: Cases were seen in 1 woman and 3 men (average age, 48.8 years; range, 40-66 years). Grossly, tumors were red-brown (3 of 4) with scant bright-yellow foci in 1. The average tumor size was 4 cm (range, 2.5-5.5 cm). Microscopically, all were composed of varying proportions of a rich, arborizing, sinusoid-like vasculature with focal hobnail appearance of endothelial cells. Entrapment of renal tubules between blood vessels was seen at the periphery of the tumors. This morphology was reminiscent of anastomosing hemangioma. Isolated tumor cells resembling lymphocytes with clear halos were sparsely interspersed between vessels. Cytokeratin immunostain confirmed the diagnosis of CCRCC. CONCLUSION: Extensive sampling and immunohistochemical workup of what is deemed to be a benign vascular neoplasm of the kidney is needed to rule out the presence of individual carcinoma cells or small viable carcinoma cell clusters.


Asunto(s)
Carcinoma de Células Renales/diagnóstico , Hemangioma/diagnóstico , Neoplasias Renales/diagnóstico , Adulto , Anciano , Carcinoma de Células Renales/irrigación sanguínea , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Diagnóstico Diferencial , Femenino , Hemangioma/irrigación sanguínea , Hemangioma/metabolismo , Hemangioma/patología , Humanos , Inmunohistoquímica , Queratinas/metabolismo , Neoplasias Renales/irrigación sanguínea , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Mucina-1/metabolismo
5.
Appl Opt ; 50(35): 6543-7, 2011 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-22193134

RESUMEN

High-frequency guided acoustic Brillouin modes have recently been observed in small-core silica photonic crystal fibers. In this paper, we investigate the temperature dependence of the optical sideband frequency generated by one of these guided acoustic waves. The experimental results show a temperature coefficient of 100 kHz/°C at an acoustic resonance frequency of 1.15 GHz and are in very good agreement with the theoretical predictions. This coefficient demonstrates a temperature sensitivity 10 times larger than that previously reported in conventional single-mode fibers, which is promising in view of potential applications to optical fiber sensors.

6.
Am J Clin Pathol ; 136(3): 450-7, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21846922

RESUMEN

We describe 3 ovarian and 5 renal anastomosing hemangiomas. One manifested with polycythemia, others were incidental; none recurred. The mean patient age was 58 years. Three hemangiomas developed in end-stage renal disease. Tumors were well-demarcated, mahogany brown, spongy lesions measuring 0.1 to 5 cm. Tortuous large vessels fed and drained tightly packed anastomosing sinusoidal capillary channels. Four hemangiomas exhibited lobular architecture, central edema/hyalinization, and intravascular growth. Five cases had thrombosis, hemorrhage, and hemosiderin. One ovarian tumor induced stromal luteinization. Three tumors had foci of extramedullary hematopoiesis (one associated with polycythemia). Six cases demonstrated eosinophilic intracytoplasmic globules. Three cases included hobnail endothelial cells. Atypia was minimal and mitoses were absent in all cases. We find this vascular neoplasm unique for the genitourinary system. Despite selected features mimicking angiosarcoma, our data support its benign nature. The current study expands the gross and radiographic appearance, clinical aspects, and ultrastructure, with the first report of the lesion occurring in the ovary.


Asunto(s)
Hemangioma/diagnóstico , Neoplasias Renales/diagnóstico , Neoplasias Ováricas/diagnóstico , Adulto , Anciano , Biomarcadores de Tumor/metabolismo , Femenino , Hemangioma/diagnóstico por imagen , Hemangioma/metabolismo , Humanos , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/metabolismo , Masculino , Persona de Mediana Edad , Neoplasias Ováricas/diagnóstico por imagen , Neoplasias Ováricas/metabolismo , Ultrasonografía
7.
Appl Immunohistochem Mol Morphol ; 19(1): 48-53, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20881840

RESUMEN

Primary sinonasal melanoma is an aggressive tumor that often presents a diagnostic challenge owing to its rarity and variable morphology. Unusual immunophenotypic expression of sinonasal melanoma compounds the problem particularly in a limited tissue sample. We studied immunohistochemical patterns of 5 primary sinonasal melanoma using antibodies against pan-cytokeratin, S-100, HMB-45, Melan-A, chromogranin, synaptophysin, neurofilament protein, and calponin and correlated these patterns with histologic appearance. Sinus/nasal mucosa from non-neoplastic cases were stained for Melan-A to evaluate prevalence of melanocytes in the benign mucosa in comparison to the staining pattern of the mucosa adjacent to the tumor. Similar to previous report, small cell pattern appeared to be over represented in the sinonasal melanoma. Small cell population in 4 cases was almost devoid of pigment, and also was either completely negative or only focally positive for S-100. Three cases stained positive for neuroendocrine markers and neurofilament protein bringing olfactory neuroblastoma and small cell neuroendocrine carcinoma in as differential diagnosis. Three cases were focally positive for calponin without spindle cell morphology or desmoplastic reaction. Immunophenotypic heterogeneity along with the unconventional histomorphology of sinonasal melanoma compounds diagnostic problem and warrants a precautionary approach to avoid misinterpretation. It is necessary to apply a broad panel of immunohistochemistry for the purpose of screening when sinonasal melanoma is considered as a differential diagnosis.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Proteínas de Unión al Calcio/metabolismo , Regulación Neoplásica de la Expresión Génica , Melanocitos/metabolismo , Proteínas de Microfilamentos/metabolismo , Neoplasias Nasales/metabolismo , Neoplasias Nasales/patología , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Inmunohistoquímica , Masculino , Melanocitos/patología , Persona de Mediana Edad , Estudios Retrospectivos , Tioridazina , Calponinas
8.
J Drug Target ; 19(7): 497-505, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20738150

RESUMEN

In order to facilitate the intracellular delivery of macromolecules, Pep-1 peptide-modified liposomal (Pep1-Lipo) nanocarriers were designed and examined for their in vitro cell translocation capability. Pep-1 peptides were coupled via thiol-maleimide linkage to small unilamellar vesicles composed of phosphatidylcholine, Tween 80, and N-[4-(p-maleimidophenyl)butyryl]-phosphatidylethanolamine (MPB-PE). The amount of Pep-1 peptide conjugated to the vesicle was effectively controlled by the amounts of maleimide groups on the vesicular surface, ranging from 70 to 700 molecules per vesicle. Systems were evaluated for cell uptake capacity by monitoring entrapped fluorescence-labeled bevacizumab, a model protein for poorly permeable macromolecule, using confocal microscopy. The novel carriers rapidly bound to the cell membrane and migrated into the cells within 1 h, exhibiting better translocation of macromolecules compared to that of conventional liposomes. Cellular uptake of Pep1-Lipo was proportional to the amount of Pep-1 peptide on the liposomal surface. In conclusion, we found that the Pep1-Lipo formulation was a promising nanocarrier system for intracellular delivery of macromolecules.


Asunto(s)
Cisteamina/análogos & derivados , Portadores de Fármacos , Liposomas , Nanopartículas , Péptidos/química , Secuencia de Aminoácidos , Línea Celular , Cisteamina/química , Fluorescencia , Datos de Secuencia Molecular , Conformación Proteica
9.
Int J Surg Pathol ; 19(1): 35-43, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21087987

RESUMEN

The authors analyzed 52 cases of female breast angiolipoma (AL). Age distribution was 25 to 80 years of age (56.81 ± 12.78). Most cases showed vascularity below 50%, and 14 cases had vascularity >50%. Cellular and low-vascularity ALs had different clinical and radiological presentations. The mean size was 7.00 ± 3.62 mm for cellular ALs and 19.61 ± 7.58 mm for low-vascularity ALs. In any paucicellular area, the authors could identify a cluster of at least 3 interconnected vessels. The endothelium was mostly flat with uniform, hyperchromatic nuclei, and mitoses and nucleoli were absent. Fibrin thrombi in proliferating capillaries were noted in 96% of cases. Low-vascularity AL can be reliably distinguished on needle core biopsy from other lipomatous and vascular tumors of the breast. Tortuosity and proliferation of capillaries with at least 3 interconnected capillary channels in 1 focus with associated fibrin thrombi constitute a very strong clue for the diagnosis of AL on a breast needle core biopsy. Definite diagnosis of cellular AL is not always feasible because of rare cases with mitotic activity and cellular atypia. Excision is often recommended for cellular AL.


Asunto(s)
Angiolipoma/patología , Neoplasias de la Mama/patología , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad
10.
Bioresour Technol ; 101(12): 4315-21, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20185302

RESUMEN

Surfactants in their impregnated forms in chitosan beads (CBs) were used for sorption of naphthalene (NAP) from aqueous solutions. Three different surfactants, Triton X-100 (TX100), cetyltrimethyl ammonium bromide (CTAB) and sodium dodecyl sulfate (SDS), were selected for this study. The results showed that surfactant-impregnated CS beads (SICBs) in the form of a separate phase surfactant were very effective for NAP sorption. The calculated molar sorption ratio (MSR(B) mol NAP/mol surfactant) of the surfactant impregnated into SICBs was much greater than the intrinsic molar solubilization ratio (MSR) in liquid phase. The high MSR(B) value could be explained by favorable configurations of surfactants in beads, such as micelles in sorbed form. The equilibrium isotherm did not follow Langmuir or Freundlich models, but followed Chapman sigmoidal equation, indicating co-operative sorption of solutes. Using SICBs as a separate phase surfactant may be a valuable tool for remediation of groundwater contaminated with hydrophobic organic compounds.


Asunto(s)
Quitosano/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Microesferas , Naftalenos/química , Tensoactivos/química , Adsorción , Modelos Químicos , Temperatura
11.
Bioresour Technol ; 101(6): 1800-6, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19962883

RESUMEN

The adsorption performance of chitosan (CS) hydrogel beads was investigated after multiwalled carbon nanotubes (MWCNTs) impregnation for the removal of congo red (CR) as an anionic dye. The study of the adsorption capacity of CS/CNT beads as a function of the CNT concentration indicated that 0.01% CNT impregnation was the most useful for enhancing the adsorption capacity. The sulfur (%) in the CS/CNT beads measured by energy dispersive X-ray (EDX) was 2.5 times higher than that of normal CS beads after CR adsorption. Equilibrium adsorption isotherm data of the CS/CNT beads exhibited better fit to the Langmuir isotherm model than to the Freundlich isotherm model, and the heterogeneity factor (n) value of the CS/CNT beads calculated from the Sips isotherm model was close to unity (0.98). The maximum adsorption capacity of CS/CNT beads obtained from the Langmuir model was 450.4 mg g(-1).


Asunto(s)
Quitosano/química , Rojo Congo/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanotubos de Carbono/química , Adsorción , Hidrogeles/química , Concentración de Iones de Hidrógeno , Residuos Industriales , Cinética , Nanotecnología/métodos , Reproducibilidad de los Resultados , Textiles , Factores de Tiempo , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Difracción de Rayos X
12.
Obes Surg ; 19(8): 1176-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19506985

RESUMEN

A 58-year-old woman with a surgical history of jejunoileal bypass in 1980 for weight reduction sought medical attention with multiple complaints. The patient had not been taking any nutritional supplements since her bypass surgery, 26 years previously. She was found to have osteomalacia, chronic diarrhea, secondary hyperparathyroidism, and hyperoxaluria with a frequent history of nephrolithiasis. Because of her severe osteodystrophy and metabolic complications, reversal of her jejunoileal bypass was recommended. Reversal of the jejunoileal bypass with a sleeve gastrectomy was performed. Laparotomy revealed brown discoloration of the entire alimentary limb with atrophy of the bypassed intestinal limb. Histologic examination of the resected small bowel demonstrated brown pigment deposits within smooth muscle cells of the bowel wall. The pigment stained positive with Fontana-Masson most likely representing lipofuscin. We report a case of brown bowel syndrome complicating jejunoileal bypass, the first case reported in the literature to the best of our knowledge.


Asunto(s)
Enfermedades Intestinales/etiología , Derivación Yeyunoileal/efectos adversos , Síndromes de Malabsorción/etiología , Trastornos de la Pigmentación/etiología , Femenino , Gastrectomía/métodos , Humanos , Enfermedades Intestinales/patología , Enfermedades Intestinales/cirugía , Lipofuscina/análisis , Síndromes de Malabsorción/patología , Síndromes de Malabsorción/cirugía , Persona de Mediana Edad , Músculo Liso/química , Músculo Liso/patología , Osteoporosis/etiología , Trastornos de la Pigmentación/patología , Trastornos de la Pigmentación/cirugía , Síndrome , Deficiencia de Vitamina D/etiología
13.
Chemosphere ; 75(10): 1307-14, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19345394

RESUMEN

Effective coagulation and separation of particles in a soil-washed solution is required for a successful soil washing process. The effectiveness of chitosan (CS), a polycationic biodegradable polymer, as a coagulant was compared to polyacrylamide (PAA) and polyaluminium chloride (PAC) for the coagulation of a soil suspension (5 gL(-1)). The effect of surfactants in the coagulation process was investigated using Triton X-100 (TX-100), a nonionic surfactant, and sodium dodecyl sulfate (SDS), an anionic surfactant. CS (5 mgL(-1)) removed 86% and 63% of the suspended soil in the presence of TX-100 (5 gL(-1)) and SDS (5 gL(-1)), respectively, after 30 min at a pH of 6. The results prove that coagulation in the presence of TX-100 is more effective than with SDS. CS was found to be more efficient compared to PAA and PAC under all coagulation conditions. The optimum concentration of CS required for maximum coagulation of soil suspension was 5 mgL(-1). PAA and PAC could not achieve the same degree soil removal as CS even after increasing their concentrations up to 50 mgL(-1). Maximum levels of 50% and 60% soil removal were achieved using PAA (50 mgL(-1)) and PAC (50 mgL(-1)), respectively, after 30 min from a 5 gL(-1) suspension containing TX-100 (5 gL(-1)). The soil coagulation process was found to decrease with an increase in the pH of the suspension, and maximum coagulation was achieved with an acidic pH.


Asunto(s)
Resinas Acrílicas/química , Hidróxido de Aluminio/química , Quitosano/química , Restauración y Remediación Ambiental/métodos , Contaminantes del Suelo/química , Suelo , Tensoactivos/química , Precipitación Química , Concentración de Iones de Hidrógeno , Octoxinol/química , Dodecil Sulfato de Sodio/química , Factores de Tiempo
14.
Bioresour Technol ; 100(17): 3862-8, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19359163

RESUMEN

The adsorption performance of CS beads impregnated with triton X-100 (TX-100) as a nonionic surfactant and sodium dodecyl sulfate (SDS) as an anionic surfactant was investigated for the removal of anionic dye (congo red) from aqueous solution. While the adsorption capacity of CS/TX-100 beads was enhanced at all concentrations of TX-100 (0.005-0.1%), the increase in the concentration of SDS above 0.01% in the CS/SDS beads gradually reduced the adsorption capacity of the beads. Equilibrium adsorption isotherm data indicated a good fit to the Sips isotherm model and a heterogeneous adsorption process. The Sips maximum adsorption capacity in dry weight of the CS/TX-100 beads was 378.79 mg/g and 318.47 mg/g for the CS/SDS beads, higher than the 223.25mg/g of the CS beads. Modification of CS beads by impregnation with nonionic surfactant, or even anionic surfactant, at low concentrations is a possible way to enhance adsorption of anionic dye.


Asunto(s)
Quitosano/química , Rojo Congo/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Microesferas , Tensoactivos/química , Agua/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Soluciones , Temperatura
16.
Bioresour Technol ; 100(11): 2803-9, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19208471

RESUMEN

The adsorption of congo red (CR) onto chitosan (CS) beads impregnated by a cationic surfactant (CTAB, cetyl trimethyl ammonium bromide) was investigated. Chitosan beads impregnated at a ratio of 1/20 of CTAB to CS (0.05% of CTAB and 1% of CS) increased the CR adsorption capacity by 2.2 times from 162.3 mg/g (0% CTAB) to 352.5 mg/g (0.05% CTAB). The CR adsorption decreased with an increase in pH of the CR solution from 4.0 to 9.0. The Sips isotherm model showed a good fit with the equilibrium experimental data and the values of the heterogeneity factor (n) indicated heterogeneous adsorption of CR onto CS/CTAB beads, as well as CS beads. The kinetic data showed better fit to the pseudo second-order rate model than to the pseudo first-order rate model. The impregnation of CS beads by cationic surfactants showed the highest adsorption capacities of CR compared to any other adsorbents and would be a good method to increase adsorption efficiency for the removal of anionic dyes in a wastewater treatment process.


Asunto(s)
Quitosano/química , Rojo Congo/aislamiento & purificación , Modelos Químicos , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Agua/química , Adsorción , Simulación por Computador , Rojo Congo/química , Filtración/métodos , Hidrogeles/química , Microesferas , Soluciones
17.
J Hazard Mater ; 166(1): 508-13, 2009 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-19111975

RESUMEN

The investigation of adsorption of nitrate onto chitosan beads modified by cross-linking with epichlorohydrin (ECH) and surface conditioning with sodium bisulfate was performed. The results indicated that both cross-linking and conditioning increased adsorption capacity compared to normal chitosan beads. The maximum adsorption capacity was found at a cross-linking ratio of 0.4 and conditioning concentration of 0.1mM NaHSO(4). The maximum adsorption capacity was 104.0 mg g(-1) for the conditioned cross-linked chitosan beads at pH 5, while it was 90.7 mg g(-1) for normal chitosan beads. The Langmuir isotherm model fit the equilibrium data better than the Freundlich model. The mean adsorption energies obtained from the Dubinin-Radushkevich isotherm model for all adsorption systems were in the range of 9.55-9.71 kJ mol(-1), indicating that physical electrostatic force was potentially involved in the adsorption process.


Asunto(s)
Quitosano/química , Nitratos/aislamiento & purificación , Sulfatos/química , Purificación del Agua/métodos , Adsorción , Reactivos de Enlaces Cruzados , Electricidad Estática , Termodinámica , Contaminantes Químicos del Agua/aislamiento & purificación
18.
Am J Dermatopathol ; 30(6): 539-44, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19033925

RESUMEN

Glomeruloid hemangiomas (GHs) are glomeruli-like capillary tufts lined by endothelial cells that contain periodic acid-Schiff (PAS) positive eosinophilic globules (EGs). These hemangiomas are characteristic cutaneous manifestation of POEMS syndrome (Polyneuropathy, Organomegaly, Endocrinopathy, M-protein, and Skin changes). Hemangiomas histologically identical to GHs but not associated with POEMS have recently been designated as papillary hemangiomas. In this report, we present solitary head and neck GHs in 3 patients, 2 without POEMS, with particular attention to the characteristic EGs. We performed immunostains for hemoglobin A, kappa and lambda light chains, factor VIII-related antigen, CD31 and CD34, PAS stain after diastase digestion (PASD), and electron microscopic examinations on routinely fixed tissues containing EGs. Eosinophilic globules stained uniformly positive for PASD but only peripherally positive for hemoglobin and light chains on surfaces, with interiors negative for antigens. Factor VIII-related antigen and CD31 and CD34 confirmed cells containing EGs to be endothelial. Electron microscopic examination suggested that EGs are enlarged secondary lysosomes (thanatosomes). These features fail to support red blood cells or immunoglobulins as EG constituents. Glomeruloid hemangiomas may be vascular proliferations stimulated by endothelial cells' protein phagocytosis but not by phagocytosis of either hemoglobin-containing red blood cells or immunoglobulins. The vascular lesions in POEMS syndrome appear identical to papillary hemangioma in cases without the other syndromic manifestations.


Asunto(s)
Eosinófilos/patología , Neoplasias de Cabeza y Cuello/patología , Hemangioma Capilar/patología , Cuerpos de Inclusión/patología , Lisosomas/patología , Síndrome POEMS/patología , Anciano , Antígenos CD34/metabolismo , Femenino , Neoplasias de Cabeza y Cuello/irrigación sanguínea , Neoplasias de Cabeza y Cuello/diagnóstico , Hemangioma Capilar/irrigación sanguínea , Hemangioma Capilar/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Neovascularización Patológica , Síndrome POEMS/complicaciones , Síndrome POEMS/diagnóstico , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Factor de von Willebrand/metabolismo
19.
J Hazard Mater ; 160(1): 13-9, 2008 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-18384951

RESUMEN

The performances of various soil washing processes, including surfactant recovery by selective adsorption, were evaluated using a mathematical model for partitioning a target compound and surfactant in water/sorbent system. Phenanthrene was selected as a representative hazardous organic compound and Triton X-100 as a surfactant. Two activated carbons that differed in size (Darco 20-40 mesh and >100 mesh sizes) were used in adsorption experiments. The adsorption isotherms of the chemicals were used in model simulations for various washing scenarios. The optimal process conditions were suggested to minimize the dosage of activated carbon and surfactant and the number of washings. We estimated that the requirement of surfactant could be reduced to 33% of surfactant requirements (from 265 to 86.6g) with a reuse step using 9.1g activated carbon (>100 mesh) to achieve 90% removal of phenanthrene (initially 100mg kg-soil(-1)) with a water/soil ratio of 10.


Asunto(s)
Carbono/química , Restauración y Remediación Ambiental/métodos , Suelo/análisis , Tensoactivos/química , Adsorción , Algoritmos , Modelos Estadísticos , Hidrocarburos Policíclicos Aromáticos/análisis , Solubilidad , Termodinámica
20.
Endocr Pract ; 14(1): 69-75, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18238743

RESUMEN

INTRODUCTION: To determine the prevalence of type 2 diabetes mellitus (DM) in patients with primary hyperparathyroidism. METHODS: Prevalence of type 2 DM in 609 patients with surgically verified primary hyperparathyroidism presenting between 1992 and 2003 in a tertiary care hospital setting was assessed retrospectively and compared with published data of type 2 DM prevalence in Michigan's general population. Diagnosis of type 2 DM was made on the basis of documentation in the medical record of fasting or random blood glucose level thresholds according to the 1997 American Diabetes Association criteria, history of diabetes mellitus, or therapy with antidiabetic medications. RESULTS: The crude prevalence rate of type 2 DM in patients with primary hyperparathyroidism was significantly higher than the prevalence in the Michigan general population (15.9% vs 7.8%, respectively; P<.001). However, this difference was not significant after age stratification except for the age group of 64 to 75 years. Because of the differential distribution of participants across age categories in the 2 groups, a standardized prevalence ratio (SPR) was estimated to account for the variance. After adjustment, there was no significant difference in the prevalence of DM between patients with primary hyperparathyroidism and the control population (SPR, 1.19 [95% confidence interval, 0.96-1.45]) except in men. CONCLUSION: The reported higher prevalence of type 2 DM in patients with primary hyperparathyroidism could not be confirmed in this large cohort of patients except for in older patients and in men. Because of the retrospective nature the study and the lack of appropriate controls, further studies are needed to confirm or refute these findings.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Hiperparatiroidismo Primario/complicaciones , Hiperparatiroidismo Primario/epidemiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Diabetes Mellitus Tipo 2/etnología , Femenino , Humanos , Hiperparatiroidismo Primario/etnología , Masculino , Michigan/epidemiología , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Caracteres Sexuales
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