Differential MAPK pathways utilized for HGF- and EGF-dependent renal epithelial morphogenesis.

Cells derived from the inner medullary collecting duct undergo in vitro branching tubulogenesis to both the c-met receptor ligand hepatocyte growth factor (HGF) as well as epidermal growth factor (EGF) receptor ligands. In contrast, many other cultured renal epithelial cells respond in this manner only to HGF, suggesting that these two receptors may use independent signaling pathways during morphogenesis. We have therefore compared the signaling pathways for mIMCD-3 cell morphogenesis in response to EGF and HGF. Inhibition of the p42/44 mitogen-activated protein kinase (MAPK) pathway with the mitogen-activated protein kinase kinase (MKK1) inhibitor PD98059 (50 microm) markedly inhibits HGF-induced cell migration with only partial inhibition of EGF-induced cell motility. Similarly, HGF-dependent, but not EGF-dependent, branching morphogenesis was more greatly inhibited by the MKK1 inhibitor. Examination of EGF-stimulated cells demonstrated that extracellular-regulated kinase 5 (ERK5) was activated in response to EGF but not HGF, and that activation of ERK5 was only 60% inhibited by 50 microm PD98059. In contrast, the MKK inhibitor U0126 markedly inhibited both ERK1/2 and ERK5 activation and completely prevented HGF- and EGF-dependent migration and branching process formation. Expression of dominant negative ERK5 (dnBMK1) likewise inhibited EGF-dependent branching process formation, but did not affect HGF-dependent branching process formation. Our results indicate that activation of the ERK1/ERK2 signaling pathway is critical for HGF-induced cell motility/morphogenesis in mIMCD-3 cells, whereas ERK5 appears to be required for EGF-dependent morphogenesis.

Expression of c-ret promotes morphogenesis and cell survival in mIMCD-3 cells.

c-Ret, a protein tyrosine kinase receptor, and its ligand glial-derived neurotropic factor (GDNF) are critical for early regulation of ureteric bud development and nephrogenesis. To address whether c-ret directly initiates epithelial cell morphogenesis, the c-ret receptor was expressed in murine inner medullary collecting duct cells (mIMCD-3, a cell line of ureteric bud origin, which has no detectable endogenous c-ret expression). Stable expression of wild-type c-ret was found to yield a constitutively tyrosine-phosphorylated receptor, with no change after the addition of GDNF. Examination of mRNA from these cells demonstrated the message for endogenous GDNF, suggesting that c-ret was potentially being constitutively activated by an autocrine mechanism. When mIMCD-3 cells stably expressing the phosphorylated c-ret receptor were cultured in a type I collagen matrix, they exhibited little GDNF-independent or -dependent branching process formation at early time points compared with the known morphogen hepatocyte growth factor (HGF) (48 h; control, 0.33 +/- 0.33; GDNF, 1.0 +/- 0.58, P = nonsignificant; and HGF, 6.33 +/- 0.33 processes/20 cell clusters, P < 0.001), whereas extended culture (7 days) under serum-free conditions revealed a marked increase in cell survival and the spontaneous development of rudimentary branching process formation. Extended culture (7 days) of c-ret-expressing clones in type I collagen with the epithelial morphogens HGF and/or epidermal growth factor (EGF) resulted in the development of complex three-dimensional spiny cysts, whereas parental mIMCD-3 cells died under these conditions. We conclude that activated c-ret appears to mediate epithelial morphogenesis by prolonging cell survival and, in conjunction with activation of the morphogenic receptors c-met and the EGF receptor, initiates the events required for very early branching morphogenesis.

Development of a research-based standard for assessment, intervention, and evaluation of pain after neonatal and pediatric cardiac surgery.

This analysis of retrospective and prospective data quantified children (age range 0-18 years, total n = 132) during their stay in a cardiothoracic intensive care unit and examined pain management and sedation practices. Data on both factors that could potentially affect pain and its management, and analgesics/sedatives ordered for and administered to subjects were collected from chart review. In the prospective group, pain intensity was measured twice daily using the Wong-Baker FACES Pain Rating Scale. Repeat cardiac surgical procedure subjects reported significantly more pain than nonrepeat subjects on the first postoperative night. Subjects with sternal incisions reported significantly more pain than subjects with submammary incisions. Not all subjects were premedicated with analgesia for invasive procedures. Significantly greater amounts of analgesia were received by the 0-3 year-old subjects. Large amounts of sedation were used, especially in children under 3 years of age. The results prompted development of a nursing standard to assess and manage pain and sedation in this population.

Regulation of dopamine-1A (D1A) receptor gene transcription.

The D1A receptor is expressed primarily in the brain and kidney. The D1A receptor gene has been cloned from human, rat and pig and is organized similarly in each species. The 5' flanking region of the D1A receptor gene is high in GC content, is TATA box-less and contains multiple Sp1 binding sites. Comparison and alignment of the nucleotide sequences within the 5' flanking and 5' untranslated regions of each gene indicates that the highest sequence identity is in the area centered approximately 100 bases upstream from the transcription start site. There are numerous binding sites for transcription factors, including Sp1 and AP-2, in the 5' flanking region. Approximately 200 bases upstream is a conserved cAMP regulatory element-like sequence. The conserved position of certain cis-acting elements in each gene suggests that the essential elements for regulated expression of the D1A receptor gene are contained within the first 300 bases of the 5' flanking region.

Analgesic administration, pain intensity, and patient satisfaction in cardiac surgical patients.

BACKGROUND: Pain can adversely affect a patient's physiological and psychological recovery, yet little is known about the pain experience of cardiac surgical patients. OBJECTIVES: To examine nursing practice regarding analgesic administration and measure pain intensity and patient satisfaction with pain management practices. METHODS: To establish baseline nursing practice regarding analgesic administration, charts were reviewed retrospectively in 50 adult cardiac surgical patients, and the same information was collected concurrently for a prospective sample of 51 patients. The subjects completed visual analogue scales as a measure of pain intensity twice daily while in the cardiothoracic intensive care unit and Pain Relief Satisfaction Questionnaires on the day after transfer from the unit. RESULTS: Patients in the prospective group received significantly more analgesia. Pain intensity was moderate (4 or greater on the Visual Analogue Scale). Women had higher overall visual analogue scale scores than did men, 4.57 versus 3.70. Patients in whom an internal mammary artery had been used as a bypass graft had significantly higher scores compared with patients with vein grafts. The Pain Relief Satisfaction Questionnaire responses indicated that 96% of the patients experienced effective pain management in the cardiothoracic intensive care unit. CONCLUSIONS: Despite receiving analgesic doses twice those reported elsewhere for similar populations, the patients in this study reported moderate pain intensity. This finding was confounded by the fact that 96% expressed satisfaction with their pain management in the cardiothoracic intensive care unit. Frequent assessment and documentation of both pain and pain relief from interventions are necessary if the healthcare team is to implement an individualized analgesic regimen.

Cloning of the dopamine-1A (D1A) receptor gene expressed in porcine renal epithelial cells.

We sought to determine the molecular identify of the dopamine-1 (D1) receptor expressed in the porcine renal epithelial cell line LLC-PK1. We first isolated a partial cDNA by the reverse transcription-polymerase chain reaction procedure and then used the partial cDNA to isolate positive overlapping clones from a porcine genomic DNA library. Sequence analysis of the gene revealed that the longest open-reading frame encoded a 446 amino acid protein that was 95% identical to the human D1A receptor. Expression studies in mammalian cells were also consistent with the clones encoding a D1 receptor. Northern blot hybridizations with LLC-PK1 poly (A+) RNA were strongly positive. The porcine D1A gene has two exons and a short intron in the 5' untranslated region. The 5' flanking region lacks a TATA and CAAT box but is high in GC content (68%) and contains multiple Sp1 binding sites. The 5' flanking region also contains numerous other cis-acting elements for transcription factors. These results indicate that the D1A receptor is the major D1 receptor expressed in LLC-PK1 cells and further suggest that LLC-PK1 cells may be a useful model to study the regulation of renal D1A receptor gene transcription.

Cloning of the porcine D1A dopamine receptor gene expressed in renal epithelial LLC-PK1 cells.

The porcine renal epithelial cell line LLC-PK1 expresses a D1 dopamine receptor coupled to stimulation of adenylyl cyclase. The molecular identity of this receptor is unknown. We isolated a partial cDNA from LLC-PK1 poly(A)+ RNA by the reverse transcription-polymerase chain reaction procedure with degenerate D1 receptor oligonucleotide primers and used the partial cDNA to screen a porcine genomic library. One such genomic clone (lambda PGD1A.1) contained an open-reading frame that encoded a 446-amino-acid protein that is 95% identical to the human D1A receptor. The functional properties of the genomic clone transiently transfected into COS-7 cells were consistent with expression of a D1 receptor. RNA hybridization analyses with LLC-PK1 poly(A)+ RNA were positive. Primer extension analysis indicated that the primary transcription initiation site of the porcine D1A gene expressed in LLC-PK1 cells is 1,033 nucleotides upstream from the translation start site. The 5'-flanking region of the gene lacks a TATA and CAAT box but is high in GC content (68%) and contains multiple Sp1 binding sites. There is a 97-bp intron within the 5'-noncoding region, separating exons 1 and 2. These results add support to the view that the D1A receptor is the major D1 receptor expressed in kidney and further suggest that LLC-PK1 cells may be a useful model for study of the regulation of the renal D1A receptor gene.

Aberrant snacking patterns and eating disorders in patients with obsessive compulsive disorder.

BACKGROUND: Appetitive symptoms, particularly carbohydrate craving, have been shown to occur in patients whose conditions responded to treatment with drugs that enhance serotonin-mediated neurotransmission. This suggested that patients with obsessive compulsive disorder (OCD) who also frequently respond to serotonergic drugs also might have similar distributions of appetitive and eating patterns. METHOD: A survey study of 170 OCD patients and 920 controls was conducted using a questionnaire that inquired about snacking behavior, including food preference, mood changes after eating, and previous diagnosis of eating disorders. The frequency responses in the two groups were tested for statistical significance. RESULTS: Significant differences were found between the OCD and control groups with respect to the reported incidence of eating disorders, snacking patterns, and mood response to food. CONCLUSION: This finding of different snacking patterns in OCD mirrors that found in other disorders that have been shown to be responsive to serotonergic drugs. The high incidence of carbohydrate snacking among OCD patients compared with the control group provides additional evidence that brain serotonin may be involved in this disorder.

Reliability analysis of the Motivation Assessment Scale: a failure to replicate.

The Motivation Assessment Scale (MAS) has been proposed as an efficient questionnaire for identifying the source of reinforcement for an individual's self-injurious behavior (SIB). A previous reliability analysis of the MAS (Durand & Crimmins, 1988) reported interrater correlation coefficients ranging from .66 to .92, based on a comparison of responses provided by classroom teachers. In this study, the reliability of the MAS was reexamined with two independent groups of developmentally disabled individuals who exhibited SIB (N = 55). For the institutional sample (n = 39), the MAS was given to two staff members (a supervisor and therapy aide) who work with the individual daily. For the school sample (n = 16), the MAS was given to the teacher and teacher's aide who taught the student. The correlational analyses completed by Durand and Crimmins (1988) were repeated; in addition, a more precise analysis of interrater reliability was calculated based on the actual number of scoring agreements between the two raters. Results showed that only 16 of the 55 raters agreed on the category of reinforcement maintaining their client's or student's SIB, that only 15% of the correlation coefficients obtained were above .80, and that none of the reliability scores based on percent agreement between raters was above 80%.

Training effects on the resolution of moving targets--dynamic visual acuity.

In initial 60-min sessions, the dynamic visual acuity (DVA) of 54 male college observers was determined over a range of target velocities (60, 90, 120, and 150 deg/s) at each of three durations (200, 400, and 600 ms). Following four 30-min practice sessions with the task, a final test session identical to the first was then conducted. Highly significant training effects on DVA were obtained; contrary to previous work, these effects were most marked for observers with initially poorer performance.

A puborectal sling in the management of anal incontinence and rectal prolapse.

A review is presented of 11 years experience in the use of a synthetic puborectal sling in the treatment of rectal prolapse and faecal incontinence. This perineal approach operation has been performed on 24 patients from 1973 to 1984. In over 60% of the patients rectal prolapse and anal incontinence were controlled.

Three score and ten.

Excluding infant and child mortality, the average "natural" life span seems to be about 70 years. It has remained so for several thousand years. It shows little sign of change. Hard work and stress appear to increase rather than decrease longevity.