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1.
Orbit ; : 1-7, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36734461

RESUMO

Congenital erythropoietic porphyria (CEP) is a rare autosomal recessive disorder in which the activity of uroporphyrinogen III synthase (UROS) is decreased. This results in the accumulation of photoreactive porphyrinogens, primarily in the skin and bone marrow. We describe a case of a patient with CEP who initially presented with scarring and shortening of the anterior and posterior lid lamella, which led to the development of lagophthalmos. Vascularized hyperkeratotic plaques in both corneas were also present. Despite treatment with topical ocular surface lubricants, corneal perforation with iris and uvea prolapse developed and evisceration of the right eye under local anesthesia was performed. The presented case suggests that despite topical therapy, ocular complications may exacerbate requiring surgical intervention, especially in the presence of lagophthalmos.

2.
Anaesthesist ; 71(4): 321-330, 2022 04.
Artigo em Alemão | MEDLINE | ID: mdl-35352131

RESUMO

Porphyrias are a group of rare, mostly inherited metabolic disorders of heme biosynthesis. Each type of porphyria results from a specific deficiency of one of the pathway enzymes, causing a characteristic accumulation and excretion of heme precursors. Diagnosis is confirmed by the biochemical detection of these porphyrins and the precursors in urine, feces and blood. Porphyrias can be classified into acute and non-acute forms. The clinical presentation is unspecific and includes acute neurovisceral and/or cutaneous symptoms. The latent phase can evolve into a potentially life-threatening acute crisis, which is often misdiagnosed. The four acute hepatic porphyrias are relevant for anesthesiologists as precipitating factors are commonly found in the perioperative setting. Safe anesthetic management in cases of known porphyria is possible by adherence to current recommendations. The immediate administration of heme arginate as specific treatment for acute attacks is decisive for the outcome.


Assuntos
Anestesia , Porfiria Aguda Intermitente , Porfirias Hepáticas , Porfirias , Heme/uso terapêutico , Humanos , Porfiria Aguda Intermitente/complicações , Porfiria Aguda Intermitente/diagnóstico , Porfiria Aguda Intermitente/terapia , Porfirias/diagnóstico , Porfirias/metabolismo , Porfirias Hepáticas/diagnóstico , Porfirias Hepáticas/terapia
3.
Cureus ; 16(3): e55558, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38576642

RESUMO

Congenital erythropoietic porphyria (CEP), also known as Gunther's disease, is an uncommon autosomal recessive disorder caused by a mutation in the uroporphyrinogen III synthase gene. This mutation results in reduced enzyme levels in heme synthesis and the accumulation of pathogenic porphyrin isomers, uroporphyrin I and coproporphyrin I, leading to the clinical manifestations of CEP. Typically, CEP manifests shortly after birth with severe cutaneous photosensitivity, blistering, ulceration, and scarring. Erythrodontia, acro-osteolysis, and skeletal abnormalities are frequently present in conjunction with it. It can even manifest in utero as hydrops fetalis, with pink or red diaper staining as an early diagnostic clue. In this case, we present a 17-year-old male with complaints of discharge over the left foot, blisters upon sunlight exposure, extensive mottled pigmentation, excessive facial hair, mutilated fingers, and verrucous growth over the toes. Using a Wood's lamp revealed pink fluorescence of teeth and ulcers on the foot. Laboratory investigations demonstrated anemia, leukocytopenia, thrombocytopenia, and elevated urine uroporphyrin 1 and coproporphyrin 1 levels. Current treatment approaches include sun protection to avoid further skin damage, beta-carotene to reduce oxidative stress, and blood transfusions to manage anemia. Stem cell transplantation remains the sole curative therapy for this exceedingly rare condition. This case report underscores the rarity and complexity of CEP and emphasizes the challenges in its management.

4.
Biomed Chromatogr ; 27(12): 1782-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23893773

RESUMO

Biological and clinical samples for porphyrin and porphyrinogen analyses by liquid chromatography-tandem mass spectrometry (LC-MS/MS) are often contaminated with poly(ethylene)glycol (PEG), which complicates the interpretation of mass spectra and characterisation of new porphyrin metabolites. Two contaminating PEG molecules (m/z 833 and m/z 835) were completely separated from uroporphyrin I (m/z 831) by travelling wave ion mobility spectrometry and characterised by tandem mass spectrometry. One of the PEG species (m/z 835) also co-eluted with uroporphyrinogen I (m/z 837) and was unresolvable by travelling wave ion mobility spectrometry/MS, therefore contaminating the MS/MS mass spectra owing to isotope distribution. These PEG species, with the [M + H](+) ions at m/z at 833 and/or m/z 835, co-eluted with uroporphyrin I and uroporphyrinogen I by LC-MS/MS and could be wrongly identified as uroporphomethenes.


Assuntos
Cromatografia Líquida/métodos , Polietilenoglicóis/química , Porfirinogênios/química , Porfirinas/química , Espectrometria de Massas em Tandem/métodos , Animais , Fígado/química , Porfirinogênios/análise , Porfirinogênios/isolamento & purificação , Porfirinas/análise , Porfirinas/isolamento & purificação , Ratos
5.
Am J Med Sci ; 363(1): 1-10, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34606756

RESUMO

BACKGROUND: Porphyrias are a group of rare diseases leading to dysregulation in heme biosynthesis and the accumulation of heme precursors, including porphyrinogens, which in their oxidized states [porphyrins] are reddish or purple. Acute hepatic porphyrias (AHP) comprise four diseases that cause acute debilitating neurovisceral attacks. Despite diagnostic advances, AHP is often undiagnosed or misdiagnosed due to a lack of disease awareness, low clinical suspicion, variable presentation, and nonspecific symptoms that mimic more common diseases. Delays in diagnosis and treatment increase the risk of serious acute and chronic complications. METHODS: In order to assess whether symptoms alone or in combination might be utilized as important indicators or "purple flags" that, when present, should alert clinicians to suspect AHP and pursue specific diagnostic testing, we conducted a comprehensive review of the literature on AHP, including cohort studies and case reports over two epochs, from 1980 to 2006 and from 2012 to 2018. RESULTS: We found that severe abdominal pain, with or without acute central nervous system manifestations and peripheral neuropathy, continues to be the most frequent symptom. Hyponatremia, change in urine color, and certain chronic symptoms were also identified as features that should raise suspicion of AHP. To improve diagnosis of AHP, clinicians need to take a broad perspective, including demographic data and medical history, into consideration. CONCLUSIONS: The clinical features of AHP continue to be severe pain, especially pain in the abdomen. Other features that should raise suspicion are autonomic, peripheral, or central neuropathies, hyponatremia, and red-purple urine color.


Assuntos
Hiponatremia , Porfirias Hepáticas , Humanos , Técnicas e Procedimentos Diagnósticos , Heme/uso terapêutico , Hiponatremia/tratamento farmacológico , Dor , Sintase do Porfobilinogênio/deficiência , Porfirias Hepáticas/diagnóstico
6.
Angew Chem Int Ed Engl ; 38(13-14): 1957-1959, 1999 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34182710

RESUMO

Stepwise dealkylation of meso-octaethylporphyrinogen 1 yields porphomethene 2 and porphodimethene 3, providing access to large quantities of these valuable intermediates. The synthetic sequence relies on SnCl4⋅2 THF, Li, and H2O; the extent of dealkylation depends on the amount of SnCl4⋅2 THF employed.

7.
Angew Chem Int Ed Engl ; 38(7): 913-915, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29711855

RESUMO

A possible binding cavity for alkali and alkaline earth metal ions: The synthesis and structural characterization of the complex shown, which was obtained from meso-octaethylporphyrinogen and calcium metal, shows that the porphyrinogen functions as a binucleating ligand with four η3 -azaallyl binding sites for two calcium cations.

8.
Angew Chem Int Ed Engl ; 40(8): 1449-1452, 2001 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-29712350

RESUMO

Through a proton-transfer reaction a porphyrinogen assists the transformation of terminal acetylenes into Ru-vinylidenes, which are the entry point to a variety of Ru-carbenes and Ru-cumulenes. The scheme (in which the porphyrinogen is stylized) shows the reversible interconversion of an acetylide into a divinylidene unit.

9.
Angew Chem Int Ed Engl ; 37(5): 652-654, 1998 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29711067

RESUMO

Lewis acid and Lewis base centers are simultaneously present in the boron-bridged thiophene-containing porphyrinogen 1 that has been synthesized in high yield. Its crystal structure reveals a nonplanar macrocycle; this and the colorless aspect suggest the absence of a delocalized π-electron system. R = NiPr2 .

10.
Angew Chem Int Ed Engl ; 37(18): 2475-2478, 1998 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-29711353

RESUMO

A 1,3,5-alternate conformation of the pyrrole rings is adopted by the calix[6]pyrrole 1 in the crystal (see picture). Compound 1 was synthesized in a two-step process and although it crystallizes in the form of the adduct 1⋅3CH3 COCH3 ⋅H2 O⋅CHCl3 , there are no solvent molecules in the cavity (cross section ca. 60Å2 ) of this macrocycle which possesses alternating dimethyl and diphenyl substitutents at the meso positions.

11.
Angew Chem Int Ed Engl ; 37(16): 2245-2248, 1998 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-29711435

RESUMO

Complexation of metal ion and counterion by the same compound is possible with zirconium meso-octaalkylporphyrinogens (structure of a dimeric complex with four encapsulated equivalents of LiH is depicted): they carry salts in the molecular ion-pair form in hydrocarbons, and function as acid-base bifunctional compounds.

12.
Angew Chem Int Ed Engl ; 40(13): 2529-2531, 2001 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29712295

RESUMO

Tunable electrophilicity/nucleophilicity by means of the redox properties of the Ru≡N group and reversible interconversion of mononuclear and dinuclear species as a result of the photolability of the Ru=N=Ru group are characteristic of the nitrido derivatives of Ru porphyrinogens. For example, 2, the product of reversible reduction of a Ru≡N precusor, reacts with 1 in the dark to form 3, which undergoes photocleavage to 1 and 2.

13.
Angew Chem Int Ed Engl ; 37(8): 1071-1072, 1998 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-29711009

RESUMO

The central core and the macrocycle skeleton of porphyrins both offer room for boron, and a gap in the chemistry of nonmetal-containing porphyrins has now been filled. In one case a four-membered B2 O2 ring coordinates to a porphyrin cavity that has been distorted to a rectangle (A), and in the other case four boron atoms are located in the meso positions of a tetrathiaporphyrinogen (B).

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