Progressive renal shrinkage after simple pyelonephritis

We present an unusual new clinical feature which developed in a patient with congenital reticular ichthyosiform erythroderma. This rare ichthyotic disorder is characterized by erythematous ichthyotic skin surrounding slowly enlarging areas of normal skin, and by a pathognomonic ultrastructural pattern, namely perinuclear deposits of a filamentous material in vacuolized keratinocytes. At the age of 18 years, a 23-year-old woman developed several irregular hyperpigmented macules on her limbs, which were almost black in colour. These lesions have not been observed in the other patients affected by the disease nor, to our knowledge, in other ichthyotic disorders. Electron microscopy and immunohistochemistry demonstrated that the lesions were strictly related to the ichthyotic skin and that their dark colour was especially due to melanosome accumulation in activated dendritic melanocytes. An unusual postinflammatory hyperpigmentation, in which the lack of pigment deposition in the keratinocytes is due to a transfer defect in pathological cells, is hypothesized. A characteristic hyperplastic stimulation of the epidermis is also taken into consideration to explain the lack of a similar picture in other erythrodermic ichthyotic disorders with a continuous inflammatory process.     

Biophysical characterisation of lysozyme binding to LPS Re and lipid A

The binding of lysozyme to bacterial deep rough mutant lipopolysaccharide (LPS) Re and to its lipid moiety lipid A, the 'endotoxic principle' of LPS, was investigated using biophysical techniques. The beta<-->alpha gel to liquid crystalline phase transition, the nature of the functional groups of the endotoxins, the secondary structure of lysozyme, and competition with polymyxin B were studied by Fourier-transform infrared spectroscopy (FTIR); the supramolecular aggregate structure of the endotoxins was determined with synchrotron radiation X-ray diffraction and the binding stoichiometry with microcalorimetry. The results were compared with those found with zwitterionic and negatively charged phospholipids. It can clearly be shown that lysozyme binds electrostatically to charged groups of the endotoxin molecules with the consequence of acyl-chain rigidification and an initiation of a transition from inverted cubic to multilamellar structures. The binding stoichiometry of endotoxin and lysozyme is a 3:1 molar ratio for both LPS Re and lipid A, indicating a dominant binding of lysozyme to the lipid A-phosphates. This could be confirmed by the analysis of a phosphate vibration and by the use of a dephospho LPS. Parallel to lysozyme binding to endotoxin, a conformational change of the secondary structure in the protein from mainly alpha helix to more unordered structures takes place, while the residual beta-sheet substructure does not exhibit a clear concentration dependence. Binding is found to be specific for the endotoxins since, for the zwitterionic phosphatidylcholine, no binding is observed and, for the negatively charged phosphatidylglycerol, only very weak binding is found. The results are discussed in the context of the ability of lysozyme to reduce endotoxicity.     

Differential behavior of (25R)-5,6-epoxyspirostan-22 alpha-O-3 beta-ol and (25R)-5,6-epoxyspirostan-22 alpha-O-3 beta, 4 beta-diol toward Dowex

The acid-catalyzed hydrolytic cleavage of the 5,6-epoxyspirostane derivatives by the cation exchange resin Dowex 50W X8 has been exploited with the goal of developing synthetic protocols toward 3,4,5,6-polyhydroxyspirostane analogs that can serve as intermediates to potential biologically active compounds. Whereas the diastereomers (25R)-5 alpha, 6 alpha-epoxyspirostan-22 alpha-O-3 beta-ol and (25R)-5 beta, 6 beta-epoxyspirostan-22 alpha-O-3 beta-ol yield two products, (25R)-6 beta-methoxyspirostan-22 alpha-O-3 beta, 5 alpha-diol and (25R)-spirostan-22 alpha-O-3 beta, 5 alpha, 6 beta-triol on Dowex treatment in water-methanol, the alpha- and beta-diastereomers of the 5,6-epoxy derivative of 3 beta, 4 beta-diol provide a single product, (25R)-3 beta, 6 beta-dihydroxy-5 alpha-spirostan-4-one, in good yields. The structures of these products have been confirmed using 1H NMR, 13C NMR, and 1H-1H J-correlated spectroscopies. Multifunctional product formation suggests tremendous utility of Dowex in steroid synthesis. The product formation has been rationalized on the basis of differential conformational constraints of the A/B rings of the different epoxides in directing the reaction course. The reaction shows an interesting example of stereoelectronic effect of a single hydroxy group in discriminating solvent participation.     

Root stimulation studies in the evaluation of patients with motor neuron disease

Nerve root stimulation may be employed in patients with motor neuron disease (MND) to rule out motor neuropathy with conduction block. The diagnostic utility of these studies is unknown, in part because the range of amplitude changes across nerve root segments in patients with active neuronal degeneration has not been well studied. We reviewed root stimulation studies in 32 patients (59 nerves) with MND and found segmental amplitude reduction from 0 to 45%, a range similar to values reported for normal subjects; there was no suggestion of conduction block based on our usual criteria.     

Immunological similarities between two cerebral substances from Schistocerca gregaria and two neurohormones from Locusta migratoria

Two neurohormones produced by two distinctive neurosecretory median cells (A1, B) of the protocerebum have been characterized in Locusta migratoria; on with a multiple functions one called neuroparsin and one stimulating the ovarian maturation called lom OMP. Using the specific immunoserum of these two neurohormones in Schistocerca gregaria, we could demonstrate the occurring of molecules related to the neuroparsin and lom OMP of Locusta. Through histology studies of the brain and corpora cardiaca complex, the immunoserum revealed the presence of the two types of these neurosecretory cells suggesting the occurring in Locusta as well as Schistocerca of the same cells releasing molecules immunologically apparented to neuroparsin and lom OMP. The results were confirmed by electrophoretic separation of corpora cardiaca extract under unreduced conditions followed by a transfer on immobilon membrane.     

Rescue therapy for the acute respiratory distress syndrome (ARDS)

The potential risk of feto-maternal haemorrhage following coelocentesis was examined in 17 singleton pregnancies at 6-11 weeks of gestation by measuring maternal serum concentration of alpha fetoprotein (AFP) before and 1 and 10 min after the procedure. There was no significant difference between the maternal serum AFP concentration before coelocentesis (median 7.5, range 4.5-21.5 IU) compared to the values at 1 min (median 8.6, range 3.9-17.8; Z = -0.504, P = 0.614), and 10 min (median 7.5, range 5.7-20.6; Z = -0.432, P = 0.666) after the procedure. These findings demonstrate that coelocentesis is not associated with significant feto-maternal haemorrhage.