A 13C solid state nuclear magnetic resonance spectroscopic study of cork cell wall structure: the effect of suberin removal

Solid state 13C NMR measurements of cork, before and after suberin removal, showed that aliphatic suberin is spatially separated from carbohydrate and lignin and experiences higher motional freedom. Two types of chain methylenes, differing in chemical shift and in dynamic properties, were identified in aliphatic suberin. Experimental evidence indicated that the more motionally hindered methylenes are those situated nearer the linkages of aliphatic suberin to the cell wall. These linkages were shown to involve -CH2O- groups, probably engaged in ester linkages to phenylpropane units and carbohydrate C6 carbons. Spectral intensity changes indicated that, during the first steps of alkaline desuberization, these linkages are broken and the shorter aliphatic suberin chains removed. Longer chains require hydrolysis of the ester linkages within the chains and are removed upon stronger alkaline treatment. T1(C), T1 rho (H) and T1 rho (C) relaxation times have shown that the removal of suberin from cork leads to a motionally restricted and more compact environment, on the megahertz and mid-kilohertz timescales. The properties of cork suberin showed that suberin organization in cork is distinct from that in potato tissue.

Outcome of cardiopulmonary resuscitation in a Portuguese university hospital

Portugal has many weak links in the so-called 'chain of survival' both in the pre-hospital and in-hospital setting. Apart from evaluating the performance of a newly implemented in-hospital cardiac arrest system, we assessed the correlation between different clinical variables and outcome after cardiopulmonary resuscitation (CPR). All resuscitation attempts during 1995 were registered using the form recommended by the European Resuscitation Council. One hundred and twenty-five patients either collapsing out-of-hospital (42; 33.6%) or having in-hospital cardiac arrest (83; 66.4%) were included in the study. The number of patients who experienced recovery of spontaneous circulation was 10 (23.8%) in the out-of-hospital group and 35 (42.2%) in the in-hospital one. Of all out-of-hospital patients, 11.9% were discharged from hospital compared with 22.8% of the in-hospital group. Asystole was the initial rhythm in a significant number of arrests. The average call-response interval of the in-hospital cardiac arrest team was under 3 min. The results from this series concur with other reported series. Although good standards of care were achieved, we are aware that this was only an isolated step in the implementation of the 'chain of survival' in our country. The authors conclude that there is an urgent need for a nationwide programme that improves the standards of care for these patients.

Immunohistochemical distribution of type VI collagen in developing human kidney

The distribution of type VI collagen was investigated immunohistochemically in the developing human kidney from 15 to 32 weeks gestational age and it was compared with that observed in the normal infantile and adult human kidney. In fetal kidney, type VI collagen was widely distributed as a fibrillar network in the subcapsularly undifferentiated mesenchyme and intertubular interstitium, and as a basement membrane-like structure around the ureteral bud branches, tubules, and collecting ducts. During nephrogenesis, type VI collagen disappeared from the induced mesenchyme close to the tips of ureteral branches, while it formed a distinct basement membrane-like structure around the early stages of nephron differentiation (comma-shaped and S-shaped bodies) and later along Bowman's capsule of capillary loop and maturing glomeruli A strong immureactivity for type VI collagen was also found in the glomerular basement membrane and mesangial areas of capillary loop and maturing glomeruli. In infantile kidney, type VI collagen showed a distribution pattern similar to that observed during the fetal period. In adult human kidney, glomerular basement membrane showed a weak positivity for type VI collagen and the basement membrane-like staining around Bowman's capsule, tubules, and collecting ducts was less evident than in fetal and infantile kidney. Our immunohistochemical findings suggest that type VI collagen is a normal component of the glomerular and extraglomerular extracellular matrix of developing human kidney and that it undergoes changes in the expression during maturation.

Carotid stenosis associated with atrial fibrillation

PURPOSE AND SETTING

To describe the prevalence and risk factors for carotid stenosis in TIA/stroke patients with non valvular atrial fibrillation (AF) and to compare clinical and CT characteristics of TIA/stroke in AF patients with and without carotid stenosis.

SUBJECTS

50 TIA/stroke patients with AF who had ultrasound investigation of the extracranial vessels, included in a prospective hospitalar registry.

RESULTS

Twenty-two patients had some degree of carotid stenosis, but only 5 had more than 50% stenosis, including one with occlusion. Stenosis was neither more frequent nor more severe on the symptomatic side. Smokers were significantly more frequent in AF patients with > 50% stenosis. Clinical and CT features were quite similar in patients with and without carotid stenosis.

CONCLUSION

The association in a TIA/Stroke patient of AF and severe carotid stenosis on the symptomatic side is exceptional. TIA/strokes related to carotid stenosis cannot be identified by their clinical/CT characteristics. Management of these patients must be decided by stratification of risk of recurrence for AF and from carotid stenosis and balance of these risks with that of endarterectomy.

Mucocutaneous histoplasmosis in AIDS

A 36-year-old man, who was an intravenous drug abuser, developed thoracic herpes zoster, paronychia, oral candidosis, necrotizing gingivitis and bilateral parotid salivary gland swelling. Granulomatous oral lesions and ulceration on the nose were shown to be due to disseminated histoplasmosis.

Therapeutic effect of TRH. T on 26 patients with myelopathy. Neurophysiatric and urological results

TRH.T is a tripeptide functioning as neurotransmitter which aids catecholamine, and especially norepinephrine, release. The neuromodulator action of TRH.T suggests that it could be helpful in the therapy of vesico-sphincteric dysfunctions. 26 patients with myelopathy were treated with TRH.T. The results show an improvement in both the neurological and urological picture. It would also seem possible that TRH.T could play an important role as a neurotransmitter and neuromodulator rather than a receptor-effector, especially in the lower urinary tract.

Clinical, genetic and fertility studies of Indians with beta S-globin gene and the influence of Hb S on Plasmodium falciparum malaria infection

Clinical studies were carried out on mild Indian sickle cell anaemia in Malaysia, and genetic and fertility studies were carried out on 101 families with and without sickle-cell haemoglobin (Hb S). The Indian sickle cell anaemia patients reached adulthood, and pregnancies and deliveries were uneventful without blood transfusion. There was no foetal wastage and the number of children produced was not significantly different from that in families without Hb S. 28 Indian patients hospitalized with Plasmodium falciparum malaria infection were also examined for their beta S genotype. P. falciparum malaria infection occurred much more frequently in individuals without Hb S than in Hb S carriers.

The alpha-globin gene adjacent to the gene for HbQ-alpha 74 Asp replaced by His is deleted, but not that adjacent to the gene for HbG-alpha 30 Glu replaced by Gln; three-fourths of the alpha-globin genes are deleted in HbQ-alpha-thalassemia

Two Chinese patients with HbQ-alpha 2 74 Asp replaced by His beta 2-alpha-thalassemia, one HbQ-alpha 2 74 or 75 Asp replaced by His beta 2 carrier, and one HbG-alpha 2 30 Glu replaced by Gln beta 2 carrier were studied to determine the number of alpha-globin genes in their chromosomes. DNA was isolated from white blood cells and bone marrow cells and studied by liquid hybridization and by hybridization of DNA fragments obtained by restriction enzyme endonuclease digestion (Ecr to nitrocellulose filters. The liquid hybridization analysis showed that in HbQ-alpha 2 74 Asp replaced by His beta 2-alpha-thalassemia, as in HbH disease, only one-fourth of the usual number of alpha-globin genes is present. Hybridization patterns of DNA restriction enzyme fragments showed that in HbQ-alpha 2 74 Asp replaced by His beta 2-alpha-thalassemia one chromosome has both alpha-globin genes deleted and the other chromosome, which carries the alpha-mutant gene, has one alpha-globin gene deleted. Our results show that the HbQ-alpha 74 Asp replaced by His structural gene is located adjacent to a deleted alpha-globin gene, whereas the alpha-globin gene adjacent to HbG-alpha 30 Glu replaced by Gln gene is not deleted.