Renal Arterial and Venous Endothelin in Hypertensive Patients with or Without Renal Artery Stenosis

Immunoreactive endothelin (ir-ET) levels were measured in the renal veins and aorta of 43 untreated hypertensive patients immediately before renal angiography. None of the patients used antihypertensive medication. Twenty-seven patients had renal artery stenosis, 17 of which were unilateral and 10 bilateral. Seven of the 17 patients with unilateral renal artery stenosis had an elevated renin ratio. Of the 16 patients with essential hypertension 6 had a unilateral small kidney with a normal blood supply. Although there was a trend towards higher levels of ir-ET in patients with renal artery stenosis, no significant differences in endothelin levels (venous or arterial) were found between different groups of patients or groups of kidneys. More than 75% of kidneys extracted endothelin, there being no significant differences between groups of kidneys. In conclusion, our data demonstrate that endothelin levels and renal endothelin extraction are comparable in essential hypertension and in hypertension associated with renal artery stenosis. Whereas renal uptake or endothelin is the rule, some kidneys, however, release this peptide irrespective of the presence or absence of renal artery stenosis.     

Xanthone additives for blood storage that maintain its potential for oxygen delivery. I. 2-Hydroxyethoxy- and 2-ethoxy-6-(5-tetrazoyl) xanthones in citrate-phosphate-dextrose-adenine (CPDA-1) blood

Two xanthones, 2-hydroxyethoxy-6-(5-tetrazoyl) (BW A440C) and 2-ethoxy- 6-(5-tetraozyl) (BW A827C), are members of a chemical series tested in vitro as potential additives to citrate-phosphate-dextrose-adenine (CPDA-1) medium for blood storage. P50 was maintained in the presence of these compounds during 42 days' storage by a partial maintenance of 2,3 diphosphoglycerate (2,3 DPG) and by a direct effect on hemoglobin previously reported for BW A827C. Red cell 2,3 DPG levels for BW A440C (n = 5), BW A827C (n = 5), and control (n = 6), respectively, were 3.38 +/− 0.47, 3.44 +/− 0.25, and 1.20 +/− 0.10 mM +/− SEM on day 7; 1.16 +/− 0.13, 1.52 +/− 0.37, and 0.16 +/− 0.02 mM on day 21; and 0.67 +/− 0.09, 0.61 +/− 0.08, and 0.06 +/− 0.006 mM on day 42. Red cell adenine triphosphate levels at the same time intervals were 1.84 +/− 0.09, 1.46 +/− 0.18, and 2.11 +/− 0.04 mM; 2.10 +/− 0.05, 2.07 +/− 0.17, and 2.13 +/− 0.05 mM; and 1.42 +/− 0.13, 1.37 +/− 0.13, and 1.38 +/− 0.06 mM, respectively. The degree of hemolysis was less with the addition of the compounds, and the methemoglobin formation, plasma Na+ and K+, and lactate production were unaffected by the compounds.     

Growth Hormone Treatment in Short Children with Chronic Renal Failure and after Renal Transplantation: Combined Data from European Clinical Trials

Growth retardation is common in children with chronic renal failure (CRF). To investigate the efficacy and safety of recombinant human growth hormone treatment in such children and in children after renal transplantation, 43 prepubertal children with CRF, and 30 prepubertal and 25 pubertal patients with a renal transplant were studied. Data are reported for 31, 26 and 17 of these patients, respectively. Median height velocity increased from 4.2 to 9.8 cm/year during the first year of treatment, and to 6.8 cm/year during the second year of treatment in the patients with CRF. In the prepubertal transplant group, median height velocity changed from 3.5 to 8.4 cm/year during the first year and to 5.4 cm/year during the second year. In the pubertal transplant group, median height velocity increased from 3.2 to 6.6 cm/year during the first year and was 4.5 cm/year during the second year. The gain in height SDS for the prepubertal children in both the CRF and transplant groups was approximately 1 SD over 2 years. Treatment was well tolerated, and renal function did not change significantly in any group.     

Non-synaptic receptors and transporters involved in brain functions and targets of drug treatment

Beyond direct synaptic communication, neurons are able to talk to each other without making synapses. They are able to send chemical messages by means of diffusion to target cells via the extracellular space, provided that the target neurons are equipped with high-affinity receptors. While synaptic transmission is responsible for the ‘what’ of brain function, the ‘how’ of brain function (mood, attention, level of arousal, general excitability, etc.) is mainly controlled non-synaptically using the extracellular space as communication channel. It is principally the ‘how’ that can be modulated by medicine. In this paper, we discuss different forms of non-synaptic transmission, localized spillover of synaptic transmitters, local presynaptic modulation and tonic influence of ambient transmitter levels on the activity of vast neuronal populations. We consider different aspects of non-synaptic transmission, such as synaptic–extrasynaptic receptor trafficking, neuron–glia communication and retrograde signalling. We review structural and functional aspects of non-synaptic transmission, including (i) anatomical arrangement of non-synaptic release sites, receptors and transporters, (ii) intravesicular, intra- and extracellular concentrations of neurotransmitters, as well as the spatiotemporal pattern of transmitter diffusion. We propose that an effective general strategy for efficient pharmacological intervention could include the identification of specific non-synaptic targets and the subsequent development of selective pharmacological tools to influence them.     

Molecular mapping of the Cromer blood group Cra and Tca epitopes of decay accelerating factor: toward the use of recombinant antigens in immunohematology

Cromer blood group antigens reside on the complement regulatory protein decay accelerating factor (DAF, CD55). This glycosyl- phosphatidylinositol-anchored glycoprotein is widely distributed, especially among cell types in contact with plasma. Numerous Cromer blood group antigens have been defined using alloantibodies induced by transfusion or pregnancy. However, few pairs of antithetical antigens have been described in this system, presumably because of the rarity of the low-frequency alleles. Analysis of polymerase chain reaction- amplified genomic DNA showed that the Cr(a-) phenotype has a Ala193-- >Pro substitution in short consensus repeat 4 (SCR4) of DAF, and the Tc(a-b+) phenotype has a Arg18-->Leu substitution in SCR1 of DAF. The locations of Cra and Tca epitopes were confirmed by analysis of Chinese hamster ovary cell transfectants expressing a Cr(a-) allele-specific transfectant and a chimeric protein containing only SCR1 of DAF, respectively. Overall, these studies further show the usefulness of an approach based on recombinant proteins in mapping blood group antigen epitopes and identifying blood group antibodies.     

Bone involvement in young patients with non-Hodgkin's lymphoma: efficacy of chemotherapy without local radiotherapy

Of 95 young non-Hodgkin's lymphoma patients entered consecutively on the National Cancer Institute (NCI) Protocol 7704, 26 (27.4%) had involvement of one or more bones. The mean age of these 26 patients was 16.6 years, and the male to female ratio was 3.3:1. Tumor histology included undifferentiated Burkitt's lymphoma in 12, undifferentiated non-Burkitt's lymphoma in two, undifferentiated, unspecified lymphoma in one, diffuse large cell lymphoma in three, and lymphoblastic lymphoma in eight patients. Most had extensive disease; two patients had isolated bone lesions, one had lesions of two bones without involvement of other tissues, and 23 had either multiple bone lesions or single bone lesions with involvement of other tissues. Eight of the 26 patients had bone marrow involvement. Of a subgroup of 12 patients with jaw disease, 11 had undifferentiated lymphoma and one had diffuse large cell lymphoma. Only one had primary a jaw tumor, with two quadrants of the jaw involved. All 26 patients were treated with chemotherapy; only two received radiotherapy initially for bone lesions. Predicted survival of the 26 patients at 5 years is 53.2%. The 12 patients who remain disease free have a mean survival of 62.1 months (range, 22 to 100 months). Our results call into question the role of radiotherapy in the treatment of bone lesions in non-Hodgkin's lymphoma.