Inhibition of the human epithelial calcium channel TRPV6 by 2-aminoethoxydiphenyl borate (2-APB)

TRPV6, a highly calcium-selective member of the transient receptor potential (TRP) channel superfamily, is a major pathway for calcium absorption in the fetal and adult body. It is expressed abundantly in the duodenum, the placenta and exocrine tissues. TRVP6 was postulated to contribute to store-operated calcium channel (SOC) activity in certain cell types such as exocrine cells. In this study, we tested 2-APB, a widely used SOC inhibitor on human TRPV6 (hTRPV6) activity using fluorescence imaging, patch clamp and radioactive tracer techniques in transiently and stably transfected HEK293 cells. We found that the basal calcium and cadmium influx was higher in HEK293 cells transfected with hTRPV6 than in non-transfected cells. 2-APB inhibited hTRPV6 activity in both transient and stably transfected cells. This effect was slightly sensitive toward extracellular calcium. The extracellular sodium concentration did not affect the inhibition of hTRPV6 by 2-APB. However, N-methyl-d-glucamine significantly diminished the inhibitory effect of 2-APB presumably through direct interaction with this compound. Furthermore, 2-APB inhibited the activity of TRPV6 orthologs but not human TRPV5. 2-APB may serve as a parental compound for the development of therapeutic strategies specifically targeting the hTRPV6 calcium channel.

Differences and similarities between spontaneous dissections of the internal carotid artery and the vertebral artery

Background and Purpose—To compare potential risk factors, clinical symptoms, diagnostic delay, and 3-month outcome between spontaneous internal carotid artery dissection (sICAD) and spontaneous vertebral artery dissection (sVAD). Methods—We compared patients with sICAD (n=668) and sVAD (n=302) treated in 3 university hospitals. Results—Patients with sICAD were older (46.3±9.6 versus 42.0±10.2 years; P<0.001), more often men (62.7% versus 53.0%; P=0.004), and presented more frequently with tinnitus (10.9% versus 3.4%; P<0.001) and more severe ischemic strokes (median National Institutes of Health Stroke Scale, 10±7.1 versus 5±5.9; P<0.001). Patients with sVAD had more often bilateral dissections (15.2% versus 7.6%; P<0.001) and were more often smokers (36.0% versus 28.7%; P=0.007). Thunderclap headache (9.2% versus 3.6%; P=0.001) and neck pain were more common (65.8% versus 33.5%; P<0.001) in sVAD. Subarachnoid hemorrhage (6.0% versus 0.6%; P<0.001) and ischemic stroke (69.5% versus 52.2%; P<0.001) were more frequent in sVAD. After multivariate analysis, sex difference lost its significance (P=0.21), and all other variables remained significant. Time to diagnosis was similar in sICAD and sVAD and improved between 2001 and 2012 compared with the previous 10-year period (8.0±10.5 days versus 10.7±13.2 days; P=0.004). In sVAD, favorable outcome 3 months after ischemic stroke (modified Rankin Scale, 0–2: 88.8% versus 58.4%; P<0.001), recurrent transient ischemic attack (4.8% versus 1.1%; P=0.001), and recurrent ischemic stroke (2.8% versus 0.7%; P=0.02) within 3 months were more frequent. Conclusions—sICAD and sVAD patients differ in many aspects. Future studies should perform separate analyses of these 2 entities.

Climate variability of the mid- and high-latitudes of the Southern Hemisphere in ensemble simulations from 1500 to 2000 AD

To increase the sparse knowledge of long-term Southern Hemisphere (SH) climate variability, we assess an ensemble of 4 transient simulations over the last 500 yr performed with a state-of-the-art atmosphere ocean general circulation model. The model is forced with reconstructions of solar irradiance, greenhouse gas (GHG) and volcanic aerosol concentrations. A 1990 control simulation shows that the model is able to represent the Southern Annular Mode (SAM), and to some extent the South Pacific Dipole (SPD) and the Zonal Wave 3 (ZW3). During the past 500 yr we find that SPD and ZW3 variability remain stable, whereas SAM shows a significant shift towards its positive state during the 20th century. Regional temperatures over South America are strongly influenced by changing both GHG concentrations and volcanic eruptions, whereas precipitation shows no significant response to the varying external forcing. For temperature this stands in contrast to proxy records, suggesting that SH climate is dominated by internal variability rather than external forcing. The underlying dynamics of the temperature changes generally point to a combination of several modes, thus, hampering the possibilities of regional reconstructing the modes from proxy records. The linear imprint of the external forcing is as expected, i.e. a warming for increase in the combined solar and GHG forcing and a cooling after volcanic eruptions. Dynamically, only the increase in SAM with increased combined forcing is simulated.

Spindle cell oncocytoma of the adenohypophysis: report of a case with a 16-year follow-up

Spindle cell oncocytoma (SCO) is a recently described, rare neoplasm of the anterior pituitary. Clinically and radiologically simulating a non-functioning macroadenoma, its eponymous fusiform cells display a non-epithelial phenotype with conspicuous cytoplasmic accumulation of mitochondria. We report a case of SCO retrospectively identified in a biopsy specimen 16 years after transsphenoidal operation of a 48-year-old woman. Presenting symptoms were adynamia and transient decrease of visual acuity. Neuroimaging showed an isointense, enhancing, sellar-centered mass 1.8 cm in diameter without evidence of invasive growth. No postoperative adjuvant therapy was administered. The patient was left with panhypopituitarism, yet no recurrence was seen during follow-up. Initially diagnosed as a null cell adenoma of oncocytic type, repeat immunohistochemistry showed the characteristic coexpression of S100 protein, vimentin, and epithelial membrane antigen. Oncocytic granula stained intensely with antimitochondrial antibody 113-1, and were negative with the lysosomal marker CD68. Anterior pituitary hormones tested negative, and there was no evidence of neuroendocrine differentiation using antibodies to synaptophysin and chromogranin. Few cells stained for glial fibrillary acidic protein (GFAP). SCO has been proposed to represent a neoplasm of folliculo-stellate cells (FSCs). While the dynamic properties of the latter are incompletely characterized, and indeed no specific marker allows for their identification, overlapping features of SCO with look alikes, in particular pituicytoma, point to FSCs being a potential adult stem cell. The favorable outcome of the present case further argues for SCO to be considered a low-grade neoplasm. Moderate tumor size, lack of invasiveness, and low proliferation rate are likely predictors of benign behavior.

The efficacy of non-pharmacological interventions in the management of procedural pain in preterm and term neonates. A systematic literature review

BACKGROUND: Neonates in a neonatal intensive care unit are exposed to a high number of painful procedures. Since repeated and sustained pain can have consequences for the neurological and behaviour-oriented development of the newborn, the greatest attention needs to be paid to systematic pain management in neonatology. Non-pharmacological treatment methods are being increasingly discussed with regard to pain prevention and relief either alone or in combination with pharmacological treatment. AIMS: To identify effective non-pharmacological interventions with regard to procedural pain in neonates. METHODS: A literature search was conducted via the MedLine, CINAHL, Cochrane Library databases and complemented by a handsearch. The literature search covered the period from 1984 to 2004. Data were extracted according to pre-defined criteria by two independent reviewers and methodological quality was assessed. RESULTS: 13 randomised controlled studies and two meta-analyses were taken into consideration with regard to the question of current nursing practice of non-pharmacological pain management methods. The selected interventions were "non-nutritive sucking", "music", "swaddling", "positioning", "olfactory and multisensorial stimulation", "kangaroo care" and "maternal touch". There is evidence that the methods of "non-nutritive sucking", "swaddling" and "facilitated tucking" do have a pain-alleviating effect on neonates. CONCLUSIONS: Some of the non-pharmacological interventions have an evident favourable effect on pulse rate, respiration and oxygen saturation, on the reduction of motor activity, and on the excitation states after invasive measures. However, unambiguous evidence of this still remains to be presented. Further research should emphasise the use of validated pain assessment instruments for the evaluation of the pain-alleviating effect of non-pharmacological interventions.

A KEL gene encoding serine at position 193 of the Kell glycoprotein results in expression of KEL1 antigen

BACKGROUND: The KEL2/KEL1 (k/K) blood group polymorphism represents 578C>T in the KEL gene and Thr193Met in the Kell glycoprotein. Anti-KEL1 can cause severe hemolytic disease of the fetus and newborn. Molecular genotyping for KEL*1 is routinely used for assessing whether a fetus is at risk. Red blood cells (RBCs) from a KEL:1 blood donor (D1) were found to have abnormal KEL1 expression during evaluation of anti-KEL1 reagents. STUDY DESIGN AND METHODS: Kell genotyping methods, including KEL exon 6 direct sequencing, were applied. KEL cDNA from D1 was sequenced. Flow cytometry was used to assess KEL1 and KEL2 RBC expression. RESULTS: RBCs from the donor, her mother, and an unrelated donor gave weak or negative reactions with some anti-KEL1 reagents. Other Kell-system antigens appeared normal. The three individuals were homozygous for KEL C578 (KEL*2) but heterozygous for a 577A>T transversion, encoding Ser193. They appeared to be KEL*2 homozygotes by routine genotyping methods. Flow cytometry revealed weak KEL1 expression and normal KEL2, similar to that of KEL*2 homozygotes. CONCLUSION: Ser193 in the Kell glycoprotein appears to result in expression of abnormal KEL1, in addition to KEL2. The mutation is not detected by routine Kell genotyping methods and, because of unpredicted KEL1 expression, could lead to a misdiagnosis.

Thoracolumbar dorsolateral laminectomy with osteotomy of the spinous process in fourteen dogs

OBJECTIVE: To describe outcome after an alternative unilateral approach to the thoracolumbar spine for dorsal laminectomy. STUDY DESIGN: Retrospective clinical study. ANIMALS: Dogs (n=14) with thoracolumbar spinal cord compression. METHODS: Thoracolumbar spinal cord compression was lateral (6 dogs), dorsal (4), and dorsolateral (4) caused by subarachnoid (7) and synovial cysts (2) and intradural-extramedullary neoplasia (5). All dogs were treated by dorsal laminectomy with osteotomy of the spinous process using a unilateral paramedian approach. The contralateral paraspinal muscles were not stripped from the spinous process and the osteoligamentous complexes were preserved. Retraction of the spinous process and muscles to the contralateral side resulted in complete visualization of the dorsal vertebral arch thereby allowing dorsal laminectomy to be performed. RESULTS: No technique complications occurred. Approximately 75% exposure of the spinal cord (dorsal and lateral compartments) was achieved providing adequate visualization and treatment of the lesions. Transient deterioration of neurologic state occurred in 5 dogs because of extensive spinal cord manipulation. At long-term follow-up, 6 dogs were normal, 6 had clinical improvement, and 2 were unchanged. CONCLUSION: Dorsal laminectomy after osteotomy and retraction of the spinous process may be considered in canine patients with dorsal, dorsolateral, or lateral compression to facilitate adequate decompression of the spinal cord. CLINICAL SIGNIFICANCE: This surgical technique offers an alternative approach to the thoracolumbar spine and spinal cord by a modified dorsal laminectomy that preserves the paraspinal muscle integrity on the contralateral side.

Insulin-like growth factors (IGFs), IGF binding proteins, and other endocrine factors in milk: role in the newborn

The role of colostrum and milk in the neonate has been chiefly recognized as a comprehensive nutrient foodstuff. In addition, the provision of colostrum-the first milk-for early immune capacity has been well documented for several species. Colostrum is additionally a rich and concentrated source of various factors that demonstrate biological activity in vitro. Three hypotheses have been proposed for the phenotypic function of these secreted bioactive components: (1) only mammary disposal, (2) mammary cell regulation, and (3) neonatal function [gastrointestinal tract (GIT) or systemic]. Traditionally, it was assumed that the development of the GIT is preprogrammed and not influenced by events occurring in the intestinal lumen. However, a large volume of research has demonstrated that colostrum (or milk-borne) bioactive components can basically contribute to the regulation of GIT growth and differentiation, while their role in postnatal development at physiological concentrations has remained elusive. Much of our current understanding is derived from cell culture and laboratory animals, but experimentation with agriculturally important species is taking place. This chapter provides an overview of work conducted primarily in neonatal calves and secondarily in other species on the effects on neonates of selected peptide endocrine factors (hormones, growth factors, in part cytokines) in colostrum. The primary focus will be on insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) and other bioactive peptides, but new interest and concern about steroids (especially estrogens) in milk are considered as well.

Is alcohol ablation of the septum associated with recurrent tachyarrhythmias?

QUESTIONS UNDER STUDY: Alcohol ablation (AA) of the septum has been introduced as new therapy in hypertrophic cardiomyopathy (HCM). It was feared that iatrogenic myocardial infarction due to AA may induce re-entry tachyarrhythmias and increase sudden cardiac death. METHODS AND RESULTS: Twenty-four patients (mean age 52 years) underwent successful AA. Clinical follow-up (FU) ranged from 0.3 to 0.7 years (mean 2.8). One patient died (suicide) 4 years after AA. Left ventricular (LV) outflow gradient (peak-to-peak) decreased (median) after AA from 43 (IQR 25 to 4) mmHg to 1 (IQR 0 to 12) mmHg (rest) (p <0.001) and from 130 (IQR 75 to 165) mmHg to 13 (IQR 0 to 31) mmHg (postextrasystolic) (p <0.001). Transient AV block occurred in 22% (5/24) necessitating temporary pacing. A permanent pacemaker was implanted in 4% (1/24). NYHA-class was 2.5 (IQR 2.0 to 3.0) before and 1.5 (IQR 1.3 to 2.0) (p <0.001) after AA. During FU, 2 pacemakers were implanted due to bradycardia (no AV block). A right bundle branch block was found in 13% (2/24) before and 46 % (11/24) after AA (p = 0.003). Non-sustained ventricular tachycardia (NSVT) was observed in 13% (2/16) before and 22% (5/23) (p = 0.46) after AA. Two patients required ICD implantation. CONCLUSIONS: Long-term FU is excellent in HCM after AA. The pressure gradient drops below 25 mm Hg in 95% (23/24) of all patients. Transient AV block occurs in 22% (5/24), but permanent pacemaker implantation is rarely needed (13%, 2/24). Severe NSVT occurs in 13% (2/16) before and 22% (5/23) after AA but ICD implantation is only occasionally required.

Neonatal macrocephaly: cerebral primitive neuroectodermal tumor or neuroblastoma as an infrequent cause--a case report and review of the literature

We report a male term newborn presenting with a congenital macrocephaly 3.5 standard deviations above the median, with a wide and tense anterior fontanel, splayed calvarial sutures, and muscular hypotonia. Antenatal head circumferences were repeatedly below the median. A postnatal head ultrasound showed a large right intracerebral mass with right lateral ventricle compression, right temporal horn dilation, and right frontal horn enlargement with lateral displacement. Additional imaging by computed tomography scan and magnetic resonance imaging was performed. A decompression was performed and histology, immunohistochemistry, and molecular biology supported the diagnosis of a primitive neuroectodermal tumor. A MYCN gene amplification assay remained negative. The incidence of neonatal brain tumors is between 1.4 and 4.1/100,000 live births. Their most common presentation is macrocephaly, hydrocephalus, stillbirth, or diagnosis by pre- or postnatal imaging. Although hydrocephaly and intra- or extracranial hemorrhage are the most frequent causes of congenital macrocephaly, this should be initially investigated by head ultrasound. A suspected malignancy will be confirmed by histopathology, immunohistochemistry, and molecular biology.

Arabidopsis WEE1 kinase controls cell cycle arrest in response to activation of the DNA integrity checkpoint

Upon the incidence of DNA stress, the ataxia telangiectasia-mutated (ATM) and Rad3-related (ATR) signaling kinases activate a transient cell cycle arrest that allows cells to repair DNA before proceeding into mitosis. Although the ATM-ATR pathway is highly conserved over species, the mechanisms by which plant cells stop their cell cycle in response to the loss of genome integrity are unclear. We demonstrate that the cell cycle regulatory WEE1 kinase gene of Arabidopsis thaliana is transcriptionally activated upon the cessation of DNA replication or DNA damage in an ATR- or ATM-dependent manner, respectively. In accordance with a role for WEE1 in DNA stress signaling, WEE1-deficient plants showed no obvious cell division or endoreduplication phenotype when grown under nonstress conditions but were hypersensitive to agents that impair DNA replication. Induced WEE1 expression inhibited plant growth by arresting dividing cells in the G2-phase of the cell cycle. We conclude that the plant WEE1 gene is not rate-limiting for cycle progression under normal growth conditions but is a critical target of the ATR-ATM signaling cascades that inhibit the cell cycle upon activation of the DNA integrity checkpoints, coupling mitosis to DNA repair in cells that suffer DNA damage.

Transient raise of endothelin-1 plasma level and reduction of ocular blood flow in a patient with optic neuritis

PURPOSE: To analyze how far an ischemic component might have been involved in optic neuritis. METHODS: Case report: a 32-year-old man with symptoms characteristic for optic neuritis underwent extensive clinical, laboratory/serological and vascular examination for systemic associations and vascular involvement. RESULTS: The patient was found to have a temporary ocular blood flow dysregulation and increased plasma endothelin-1 levels which decreased after the acute phase of the optic nerve. CONCLUSIONS: We conclude that there might be an ischemic component in this patient with optic neuritis and hypothesize that this ischemic component is at least in part due to a temporarily increased endothelin-1 level.

Surface uplift and climate change - the geomorphic evolution of the western escarpment of the Andes of northern Chile between the Miocene and present

The Western Escarpment of the Andes at 18.30°S (Arica area, northern Chile) is a classical example for a transient state in landscape evolution. This part of the Andes is characterized by the presence of >10,000 km2 plains that formed between the Miocene and the present, and >1500 m deeply incised valleys. Although processes in these valleys scale the rates of landscape evolution, determinations of ages of incision, and more importantly, interpretations of possible controls on valley formation have been controversial. This paper uses morphometric data and observations, stratigraphic information, and estimates of sediment yields for the time interval between ca. 7.5 Ma and present to illustrate that the formation of these valleys was driven by two probably unrelated components. The first component is a phase of base-level lowering with magnitudes of∼300–500 m in the Coastal Cordillera. This period of base-level change in the Arica area, that started at ca. 7.5 Ma according to stratigraphic data, caused the trunk streams to dissect headward into the plains. The headward erosion interpretation is based on the presence of well-defined knickzones in stream profiles and the decrease in valley widths from the coast toward these knickzones. The second component is a change in paleoclimate. This interpretation is based on (1) the increase in the size of the largest alluvial boulders (from dm to m scale) with distal sources during the last 7.5 m.y., and (2) the calculated increase in minimum fluvial incision rates of ∼0.2 mm/yr between ca. 7.5 Ma and 3 Ma to ∼0.3 mm/yr subsequently. These trends suggest an increase in effective water discharge for systems sourced in the Western Cordillera (distal source). During the same time, however, valleys with headwaters in the coastal region (local source) lack any evidence of fluvial incision. This implies that the Coastal Cordillera became hyperarid sometime after 7.5 Ma. Furthermore, between 7.5 Ma and present, the sediment yields have been consistently higher in the catchments with distal sources (∼15 m/m.y.) than in the headwaters of rivers with local sources (<7 m/m.y.). The positive correlation between sediment yields and the altitude of the headwaters (distal versus local sources) seems to reflect the effect of orographic precipitation on surface erosion. It appears that base-level change in the coastal region, in combination with an increase in the orographic effect of precipitation, has controlled the topographic evolution of the northern Chilean Andes.

Implementation of the conjugate heat transfer code in KIVA-4

KIVA is an open Computational Fluid Dynamics (CFD) source code that is capable to compute the transient two and three-dimensional chemically reactive fluid flows with spray. The latest version in the family of KIVA codes is the KIVA-4 which is capable of handling the unstructured mesh. This project focuses on the implementation of the Conjugate Heat Transfer code (CHT) in KIVA-4. The previous version of KIVA code with conjugate heat transfer code has been developed at Michigan Technological University by Egel Urip and is be used in this project. During the first phase of the project, the difference in the code structure between the previous version of KIVA and the KIVA-4 has been studied, which is the most challenging part of the project. The second phase involves the reverse engineering where the CHT code in previous version is extracted and implemented in KIVA-4 according to the new code structure. The validation of the implemented code is performed using a 4-valve Pentroof engine case. A solid cylinder wall has been developed using GRIDGEN which surrounds 3/4th of the engine cylinder and heat transfer to the solid wall during one engine cycle (0-720 Crank Angle Degree) is compared with that of the reference result. The reference results are nothing but the same engine case run in the previous version with the original code developed by Egel. The results of current code are very much comparable to that of the reference results which verifies that successful implementation of the CHT code in KIVA-4.