The mouse Pax21Neu mutation is identical to a human PAX2 mutation in a family with renal-coloboma syndrome and results in developmental defects of the brain, ear, eye, and kidney

We describe a new mouse frameshift mutation (Pax2^1Neu) with a 1-bp insertion in the Pax2 gene. This mutation is identical to a previously described mutation in a human family with renal-coloboma syndrome [Sanyanusin, P., McNoe, L. A., Sullivan, M. J., Weaver, R. G. & Eccles, M. R. (1995) Hum. Mol. Genet. 4, 2183–2184]. Heterozygous mutant mice exhibit defects in the kidney, the optic nerve, and retinal layer of the eye, and in homozygous mutant embryos, development of the optic nerve, metanephric kidney, and ventral regions of the inner ear is severely affected. In addition, we observe a deletion of the cerebellum and the posterior mesencephalon in homozygous mutant embryos demonstrating that, in contrast to mutations in Pax5, which is also expressed early in the mid-hindbrain region, loss of Pax2 gene function alone results in the early loss of the mid-hindbrain region. The mid-hindbrain phenotype is similar to Wnt1 and En1 mutant phenotypes, suggesting the conservation of gene regulatory networks between vertebrates and Drosophila.     

Experiences of Urban African Americans with Cancer Pain

The experience of cancer pain is poorly understood from the perspective of African Americans, who experience higher levels of pain, more pain-related distress, and poorer function than Caucasians. Decreased perceived control over pain may play a greater role for African American patients, affecting pain-related distress and function. The purpose of this study was to add to the understanding of cancer pain and perceived control over pain in African Americans, from the patients’ perspective. This qualitative inquiry was part of a larger mixed-methods study testing an intervention to improve pain, pain-related distress, and functional status through increasing perceived control over pain. Participants were recruited from the waiting room of an urban comprehensive cancer and interviewed in their homes. Interviews with 18 adult cancer patients who self-identified as African American and reported experiencing moderate to severe pain (>4 on a 0–10 scale) within the past two weeks were included. Qualitative interviews were audiotaped, transcribed, and analyzed using a constant comparative method. Two major themes emerged from this qualitative inquiry: struggles of the chronic pain experience and benefits of perceived control over pain. Each theme contained several categories. The study unveiled the participants account of both struggles of the chronic pain experience and barriers of perceived control that can be assessed for and targeted in nursing intervention. Benefits to having perceived control over pain were also illustrated in the participants’ narratives.     

Growth, growth factors and diabetes

Type 1 diabetes mellitus (T1DM) and other chronic diseases in children are well known to adversely affect linear growth and pubertal development. In the years immediately following the introduction of insulin therapy, short stature was consistently reported in children with T1DM. However, over the past 50 years significant improvement in the prognosis for growth and final height in children with diabetes has been achieved. Although pre-pubertal and post-pubertal growth are important phases in growth, puberty and its related hormonal changes represent a critical phase for growth gain and final height particularly in patients with T1DM. Growth impairment reported in diabetic patients is dependent on abnormalities in physiological bone growth and corresponds to abnormalities of the growth hormone-insulin-like growth-I (GH-IGF-I) axis. These alterations seem to be related to appropriate insulin levels and thereby to glycaemic control as judged by haemoglobin levels. Modern diabetes care, particularly intensified insulin regimens, might improve metabolic control in patients with T1DM, therefore preventing abnormalities of the GH-IGF-I axis and leading to normal growth and final height similar to that of their unaffected peers.     

A role for fast rhythmic bursting neurons in cortical gamma oscillations in vitro

Basic cellular and network mechanisms underlying gamma frequency oscillations (30-80 Hz) have been well characterized in the hippocampus and associated structures. In these regions, gamma rhythms are seen as an emergent property of networks of principal cells and fast-spiking interneurons. In contrast, in the neocortex a number of elegant studies have shown that specific types of principal neuron exist that are capable of generating powerful gamma frequency outputs on the basis of their intrinsic conductances alone. These fast rhythmic bursting (FRB) neurons (sometimes referred to as "chattering" cells) are activated by sensory stimuli and generate multiple action potentials per gamma period. Here, we demonstrate that FRB neurons may function by providing a large-scale input to an axon plexus consisting of gap-junctionally connected axons from both FRB neurons and their anatomically similar counterparts regular spiking neurons. The resulting network gamma oscillation shares all of the properties of gamma oscillations generated in the hippocampus but with the additional critical dependence on multiple spiking in FRB cells.     

Plasma lidocaine concentrations after local anesthesia of the groin for cardiac catheterization.

This study aimed to investigate serum lidocaine concentrations after subcutaneous infiltration of the groin for cardiac catheterization. One hundred twenty-six patients for planned heart catheterization received five different dosages (5-25 ml) of lidocaine 2% for local anesthesia of the groin in a randomized manner. All of them received an arterial sheath and 13 received both an arterial sheath and a venous sheath for right heart catheterization. Blood samples were taken before as well as 15, 30, and 120 min after subcutaneous application of the drug. Although in 33 patients with an arterial sheath (no venous sheath) excessive doses of lidocaine 2% (20-25 ml) were used, neither symptoms of intoxication nor toxic plasma levels were observed. However, in patients receiving an additional venous sheath, toxic plasma levels were obtained in a third of the cases. One of them showed symptoms of intoxication.     

Hepatocyte cytoskeleton during ischemia and reperfusion--influence of ANP-mediated p38 MAPK activation

AIM: To determine functional consequences of this activation, whereby we focused on a potential regulation of the hepatocyte cytoskeleton during ischemia and reperfusion. METHODS: For in vivo experiments, animals received ANP (5 μg/kg) intravenously. In a different experimental setting, isolated rat livers were perfused with KH-buffer ±ANP (200 nmol/L)±SB203580 (2 μmol/L). Livers were then kept under ischemic conditions for 24 h, and either transplanted or reperfused. Actin, Hsp27, and phosphorylated Hap27 were determined by Western blotting, p38 MAPK activity by in vitro phosphorylation assay. F-actin distribution was determined by confocal microscopy. RESULTS: We first confirmed that ANP preconditioning leads to an activation of p38 MAPK and observed alterations of the cytoskeleton in hepatocytes of ANP-preconditioned organs. ANP induced an increase of hepatic F-actin after ischemia, which could be prevented by the p38 MAPK inhibitor SB203580 but had no effect on bile flow. After ischemia untreated livers showed a translocation of Hsp27 towards the cytoskeleton and an increase in total Hsp27, whereas ANP preconditioning prohibited translocation but caused an augmentation of Hsp27 phosphorylation. This effect is also mediated via p38 MAPK, since it was abrogated by the p38 MAPK inhibitor SB203580. CONCLUSION: This study reveals that ANP-mediated p38 MAPK activation leads to changes in hepatocyte cytoskeleton involving an elevation of phosphorylated Hsp27 and thereby for the first time shows functional consequences of ANP-induced hepatic p38 MAPK activation.     

Kupffer-cell specific induction of heme oxygenase 1 (hsp32) by the atrial natriuretic peptide--role of cGMP

BACKGROUND/AIMS: Pretreatment with atrial natriuretic peptide (ANP) attenuates ischemia-reperfusion injury of livers via cGMP. Heme oxygenase-1 (HO-1) is known as a protective mediator in ischemia-reperfusion injury. The aim of this study was to investigate whether ANP affects the expression of HO-1. METHODS: Rat livers were perfused with KH-buffer with/without ANP or 8-Br-cGMP, kept in UW solution (4 degrees C, 24 h), and reperfused. HO-1 mRNA and protein was determined by Northern and Western blot, in situ hybridization, and immunohistochemistry in livers or isolated liver cells. RESULTS: ANP significantly elevated HO-1 mRNA expression at the end of the preconditioning period and was without effects at the end of ischemia and during reperfusion. 8-Br-cGMP did not affect HO-1 mRNA expression. In situ hybridization as well as immunohistological double-staining revealed that Kupffer cells but not hepatocytes showed HO-1 mRNA and protein expression. Hepatocytes revealed no changes in HO-1 protein whereas Kupffer cells showed a marked increase in HO-1 protein after ANP treatment. Inhibition of HO-1 did not abrogate hepatoprotection conveyed by ANP. CONCLUSION: Our data show the potency of ANP to specifically induce HO-1 in Kupffer cells independently of cGMP. This increased expression of HO-1 is not involved in hepatoprotection conferred by ANP being in line with the knowledge that ANP mediates hepatoprotection via cGMP.