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1.
BMJ Case Rep ; 20182018 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-30361453

RESUMO

Calciphylaxis is a rare and life-threatening disease characterized by cutaneous arteriolar stenosis and vascular thrombosis leading to skin ischaemia and necrosis. While calciphylaxis occurs mostly in patients with end-stage renal disease, the disorder has been described in patients with normal renal function, namely non-uraemic calciphylaxis (NUC). A 41-year-old African-American woman presented with a painful ulcerative rash on her thighs and right buttock 2 months after undergoing an orthotopic liver transplantation. She underwent debridement of the lesions and an excisional biopsy of one of the lesions, which revealed calciphylaxis. She was treated with sodium thiosulfate, cinacalcet and hyperbaric oxygen with complete resolution of the lesions 4-5 months after presentation. While she was treated with a course of high-dose glucocorticoids after the transplant, she did not have other risk factors for calciphylaxis. NUC should be considered in the differential diagnosis of necrotic skin lesions in postliver transplant patients.


Assuntos
Calciofilaxia/etiologia , Transplante de Fígado/efeitos adversos , Adulto , Nádegas , Feminino , Humanos , Complicações Pós-Operatórias/etiologia , Fatores de Risco , Transplantados , Transplante Homólogo
2.
BMJ Case Rep ; 20182018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29724875

RESUMO

Anti-N-methyl-D-aspartic acid-receptor (NMDA-R) encephalitis is a novel disease discovered within the past 10 years. It is an autoimmune disease (AD) that has been associated with other ADs, such as Graves' disease. However, association with autoimmune polyglandular syndromes (APS) has not been previously described. A 58-year-old woman presented with altered mental status and an 8-month history of weight loss, apathy and somnolence. Laboratory evaluation confirmed Graves' disease with thyrotoxicosis and type 1 diabetes mellitus. Despite treatment, she continued to have a fluctuating mental status. Further diagnostic evaluation included an abdominal MRI that showed a cystic lobular left adnexal mass. Serum anti-NMDA-R antibodies were positive, raising concern for NMDA-R encephalitis. Bilateral salpingo-oophorectomy was performed, with pathology consistent with cystadenofibroma. She had a favourable recovery with marked clinical improvement. Anti-NMDA-R antibodies were negative 2 months following surgery. The concomitant occurrence of APS and anti-NMDA-R encephalitis suggests a shared mechanism of autoimmune pathophysiology.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico , Poliendocrinopatias Autoimunes/diagnóstico , Receptores de N-Metil-D-Aspartato/sangue , Abdome/diagnóstico por imagem , Encefalite Antirreceptor de N-Metil-D-Aspartato/complicações , Encefalite Antirreceptor de N-Metil-D-Aspartato/imunologia , Encefalite Antirreceptor de N-Metil-D-Aspartato/terapia , Anticorpos/sangue , Antitireóideos/uso terapêutico , Cistoadenofibroma/complicações , Cistoadenofibroma/diagnóstico por imagem , Cistoadenofibroma/patologia , Cistoadenofibroma/cirurgia , Diabetes Mellitus Tipo 1/complicações , Feminino , Doença de Graves/complicações , Humanos , Imageamento por Ressonância Magnética , Metimazol/uso terapêutico , Pessoa de Meia-Idade , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Poliendocrinopatias Autoimunes/complicações , Poliendocrinopatias Autoimunes/imunologia , Poliendocrinopatias Autoimunes/terapia
3.
J Clin Exp Hepatol ; 7(3): 269-273, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28970716

RESUMO

Elevated serum ferritin level is a common finding in iron overload syndrome, autoimmune and viral hepatitis, alcoholic and nonalcoholic fatty liver diseases. High transferrin saturation is not a common finding in above diseases except for iron overload syndrome. We encountered a challenging case of 73-year-old female who presented with yellowish discoloration of skin, dark color urine and dull abdominal pain. Initial laboratory tests reported mild anemia; elevated bilirubin, liver enzymes, and transferrin saturation. We came to the final diagnosis of autoimmune hepatitis after extensive workups. Autoimmune hepatitis is a rare disease, and the diagnosis can be further complicated by a similar presentation of iron overload syndrome. Markedly elevated transferrin saturation can simulate iron overload syndrome, but a liver biopsy can guide physicians to navigate the diagnosis.

4.
Int J STD AIDS ; 28(3): 302-305, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27566775

RESUMO

Immune reconstitution inflammatory syndrome (IRIS) is a condition associated with paradoxical worsening and/or new onset of an opportunistic infection in HIV patients following the initiation of anti-retroviral therapy or switching to more potent antiretroviral therapy (ART) regimen. Although IRIS associated with many opportunistic infections (OIs) has been well reported, syphilis has very rarely been mentioned in this regard. A 52-year-old male, diagnosed with AIDS six weeks ago, presented with the disseminated non-pruritic painless skin rash. He denied any fever, cough, shortness of breath, and joint pain or swelling. The patient had no similar symptoms, genital ulcers, or any medical illness in the past. CD4 cell count and viral load were 40 cells/mm3 and 280,000 copies/ml, respectively, while screening tests for OIs including rapid plasma reagin test, quantiferon, cryptococcal antigen, and toxoplasma tests were negative at the time of HIV diagnosis. After three days of initiation of anti-retroviral therapy, he developed the above-mentioned skin rash. Repeat rapid plasma regain (RPR) test at this time was also negative. Punch biopsy of the skin lesion demonstrated findings suggestive of secondary syphilitic lesions, which was confirmed by immunostain. The repeat RPR, CD4 cell count, and viral load showed a titer of 1:256, 257 cells/mm3, and 5000 copies/ml, respectively. His skin rashes faded away, and RPR titer trended down on treatment with benzathine penicillin without discontinuation of ART. The presence of an IRIS response does not predict overall HIV or OI treatment responses, and discontinuation of ART is not generally recommended as the benefits of treating HIV infection outweighs the risk associated with IRIS.


Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Síndrome Inflamatória da Reconstituição Imune/etiologia , Penicilina G Benzatina/uso terapêutico , Sífilis/complicações , Contagem de Linfócito CD4 , Infecções por HIV/complicações , Humanos , Síndrome Inflamatória da Reconstituição Imune/diagnóstico , Síndrome Inflamatória da Reconstituição Imune/imunologia , Síndrome Inflamatória da Reconstituição Imune/patologia , Masculino , Pessoa de Meia-Idade , Sífilis/diagnóstico , Sífilis/tratamento farmacológico , Sorodiagnóstico da Sífilis , Resultado do Tratamento , Carga Viral
5.
Case Rep Crit Care ; 2016: 8531591, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27144037

RESUMO

Bariatric surgery is well established in reducing weight and improving the obesity-associated morbidity and mortality. Hyperammonemic encephalopathy following bariatric surgery is rare but highly fatal if not diagnosed in time and managed aggressively. Both macro- and micronutrients deficiencies play a role. A 42-year-old Hispanic female with a history of Roux-en-Y Gastric Bypass Procedure was brought to ED for progressive altered mental status. Physical exam was remarkable for drowsiness with Glasgow Coma Scale 11, ascites, and bilateral pedal edema. Labs showed elevated ammonia, low hemoglobin, low serum prealbumin, albumin, HDL, and positive toxicology. She remained obtunded despite the treatment with Narcan and flumazenil and the serum ammonia level fluctuated despite standard treatment with lactulose and rifaximin. Laboratory investigations helped to elucidate the etiology of the hyperammonemia most likely secondary to unmasking the functional deficiency of the urea cycle enzymes. Hyperammonemia in the context of normal liver function tests becomes diagnostically challenging for physicians. Severe hyperammonemia is highly fatal. Early diagnosis and aggressive treatment can alter the prognosis favorably.

6.
J Phys Chem B ; 114(40): 12840-6, 2010 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-20845947

RESUMO

The molecular mobility of a MOF-5 metal-organic framework was investigated by broadband dielectric spectroscopy. Three relaxation processes were revealed. The temperature dependence of their relaxation rates follows an Arrhenius law. The process observed at lower temperatures is attributed to bending fluctuations of the edges of the cages involving the Zn-O clusters. The processes ("region II") at higher temperatures were assigned to fluctuations of phenyl rings in agreement with the NMR data found by Gould et al. (J. Am. Chem. Soc. 2008, 130, 3246). The carboxylate groups might also be involved. The rotational fluctuations of the phenyl rings leading to the low frequency part of relaxation region II might be hindered either by some solvent molecules entrapped in the cages or by an interpenetrated structure and have a broad distribution of activation energies. The high frequency part of region II corresponds nearly to a Debye-like process: This is explained by a well-defined structure of empty pores.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 75(4): 1228-35, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20097599

RESUMO

Composites prepared from aerosil A380 and liquid crystals (LCs) of 4-n-alkyl-4'-cyanophenyl benzoate type, with four to six carbon atoms in the alkyl chain were investigated by infrared spectroscopy. Their high silica content (of 2-7 g aerosil/1 g of LC) was given by thermogravimetric investigations and allows the observation of a rather thin LC layer on the silica particles. Several surface species onto the external surface of the grains were demonstrated. Arguments are given that monomer and dimer species are present in the bulk cyanophenyl benzoate materials while bulk-like species along with hydrogen-bonded ones coexist in the so-called surface layer of the composites. The main interaction of LC molecules with the aerosil surface is by hydrogen bonding taking place with the involvement of the cyan group. There is a contribution of ester carbonyl group to these surface interactions but this cannot be well quantified.


Assuntos
Benzoatos/química , Ésteres/química , Dióxido de Silício/química , Varredura Diferencial de Calorimetria , Transição de Fase , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Temperatura , Termogravimetria
9.
Artigo em Inglês | MEDLINE | ID: mdl-19110465

RESUMO

Confinement of 4-n-octyl-4'-cyanobiphenyl (8CB) to nanoporous molecular sieves with hexagonal structure of cylindrical pores (4.6nm diameter) is studied. Thermogravimetric investigations have indicated that the pores are completely filled. Several surface species inside the pores and onto the external surface of the grains were demonstrated by differential thermal analysis and by in situ infrared spectroscopy. Arguments are given that bulk-like monomer and dimer species along with hydrogen bonded ones might coexist in the so-called surface layer, but their population varies drastically as function of the temperature. In addition, chemical changes of the confined liquid crystal are quite possible inside these nanopores, at temperatures lower than for the bulk.


Assuntos
Compostos de Bifenilo/química , Nitrilas/química , Polímeros/química , Nanoestruturas/química , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 78(5 Pt 1): 051701, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19113137

RESUMO

The molecular dynamics of 4-n-octyl-4'-cyanobiphenyl (8CB) confined inside the pores of a series of AlMCM-41 samples with the same structure, constant composition (SiAl=14.7) but different pore sizes (diameter between 2.3 and 4.6 nm) was investigated by broadband dielectric spectroscopy (10(-2)-10(9) Hz) in a large temperature interval. Two relaxation processes are observed: one has a bulklike behavior and is assigned to the 8CB in the pore center. The relaxation time of the second relaxation process is essentially slower than that of the former one and this process is related to the dynamics of molecules in a surface layer with a paranematic order. Both relaxation processes are specifically influenced by the interaction of the molecules with the surface and by the confinement. Above the clearing temperature the temperature dependence of the relaxation rate of the bulklike process obeys the Vogel-Fulcher-Tammann (VFT) law. The Vogel temperature increases with decreasing pore size. This is explained by increasing influence of paranematic potential of the surface layer with decreasing pore size. The temperature dependence of the relaxation rate of the surface layer follows also the VFT formula and the Vogel temperature decreases with decreasing pore size. This temperature dependence is controlled by both the interaction of the 8CB molecules with the surface via hydrogen bonding and by spatial confinement effects. To discriminate between both effects the data for the surface layer of 8CB confined to the molecular sieves are compared with results concerning 8CB adsorbed as a quasimonolayer on the surface of silica spheres of aerosil. On this basis a confinement parameter is defined and discussed.

11.
J Phys Chem A ; 111(24): 5166-75, 2007 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-17536791

RESUMO

The rotational molecular dynamics of water confined to layered oxide materials with brucite structure was studied by dielectric spectroscopy in the frequency range from 10(-2) to 10(7) Hz and in a broad temperature interval. The layered double hydroxide samples show one relaxation process, which was assigned to fluctuations of water molecules forming a layer, strongly adsorbed to the oxide surface. The temperature dependence of the relaxation rates has an unusual saddlelike shape characterized by a maximum. The model of Ryabov et al. (J. Phys. Chem. B 2001, 105, 1845) recently applied to describe the dynamics of water molecules in porous glasses is employed also for the layered materials. This model assumes two competing effects: rotational fluctuations of water molecules that take place simultaneously with defect formation, allowing the creation of free volume necessary for reorientation. The activation energy of rotational fluctuations, the energy of defect formation, a pre-exponential factor, and the defect concentration are obtained as main parameters from a fit of this model to the data. The values of these parameters were compared with those found for water confined to nanoporous molecular sieves, porous glasses, or bulk ice. Several correlations were discussed in detail, such as the lower the value of the energy of defect formation, the higher the number of defects. The pre-exponential factor increases with increasing activation energy, as an expression of the compensation law, and indicates the cooperative nature of the motional process. The involvement of the surface OH groups and of the oxygen atoms of the interlayer anions in the formation of hydrogen bonds was further discussed. For the birnessite sample, the relaxation processes are probably overlaid by a dominating conductivity contribution, which is analyzed in its frequency and temperature dependence. It is found that the conductivity of birnessite obeys the characteristics of semiconducting disordered materials. Especially the Barton/Nakajima/Namikawa relationship is fulfilled. Analyzing the temperature dependence of the direct current (dc) conductivity sigma0 in detail gives some hint that sigma0(T) has also an unusual saddlelike form.


Assuntos
Óxidos/química , Teoria Quântica , Água/química , Ligação de Hidrogênio , Hidroxilação , Teste de Materiais , Modelos Químicos , Oxigênio/química , Análise Espectral , Temperatura
12.
J Phys Chem B ; 109(18): 9154-9, 2005 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-16852089

RESUMO

The rotational molecular dynamics of water confined to nanoporous molecular sieves of a regular hexagonal (SBA-15) and of a foamlike pore structure was studied by dielectric spectroscopy in the frequency range from 10(-2) to 10(9) Hz and in a broad temperature interval. Two relaxation processes were observed: the process at lower frequencies is related to water molecules forming a layer, which is strongly adsorbed at the pore surface, whereas the relaxation process at higher frequencies is assigned to fluctuations of water molecules situated close to the center of the pore. The relaxation times of the low-frequency process for both materials and of the high-frequency process for the SBA-15 material have an unusual saddlelike temperature dependence, reported here for the first time. To describe this temperature dependence, a model developed for water confined to nanoporous glasses by Ryabov et al. [J. Phys. Chem. B 2001, 105, 1845] was applied, which considers two competing effects. The characteristic features of these two competing processes were compared with those reported for other porous systems.

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