Expression and imaging of connexin-GFP chimeras in live mammalian cells.
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
K Jordan
Publications and source records attributed to K Jordan.
Thirteen-year follow-up of children and adolescents with chronic fatigue syndrome.
OBJECTIVE: To describe the educational, social, and symptomatic outcome of children and adolescents with chronic fatigue syndrome 13 years after illness onset. METHODS: Between January 1984 and December 1987, 46 children and adolescents developed an illness suggestive of chronic fatigue syndrome. Follow-up questionnaires were obtained from 35 participants an average of 13 years after illness onset. Data were obtained concerning subsequent medical diagnoses, amount of school missed, presence and severity of current symptoms, and subjective assessment of degree of illness resolution. RESULTS: Of the 35 participants, 24 were female (68.6%) and 11 were male (31.4%). Average age at illness onset was 12.1 years. Eight participants (22.9%) had an acute onset of symptoms, 27 (77.1%) had a gradual onset. No participant received an alternative medical diagnosis that could have explained the symptom complex between illness onset and follow-up. Thirteen participants (37.1%) considered themselves resolved of illness at follow-up; 15 participants (42.9%) considered themselves well but not resolved; 4 (11.4%) considered themselves chronically ill; and 3 (8.6%) considered themselves more ill than during the early years of illness. Correlation with the Medical Outcomes Study Short Form Health Survey was good for current level of symptoms and degree of recovery. Eight participants (22.9%) missed >2 years of school, and 5 of these were still ill at follow-up. Amount of school missed correlated with both illness severity at follow-up and perceived social impact of the illness. CONCLUSIONS: These data demonstrate the presence of an illness consistent with the current definition of chronic fatigue syndrome. Eighty percent of children and adolescents affected had a satisfactory outcome from their fatiguing illness, although the majority of these participants had mild to moderate persisting symptoms. Twenty percent of participants remain ill with significant symptoms and activity limitation 13 years after illness onset. Chronic fatigue syndrome in children and adolescents may result in persistent somatic symptoms and disability in a minority of those affected.
Absenteeism↗
Role of cytoskeletal elements in the recruitment of Cx43-GFP and Cx26-YFP into gap junctions.
Cytoskeletal elements may be important in connexin transport to the cell surface, cell surface gap junction plaque formation and/or gap junction internalization. In this study, fluorescence recovery after photobleaching was used to examine the role of microfilaments and microtubules in the recruitment and coalescence of green fluorescent protein-tagged Cx43 (Cx43-GFP) or yellow fluorescent tagged-Cx26 (Cx26-YFP) into gap junctions in NRK cells. In untreated cells, both Cx26-YFP and Cx43-GFP were recruited into gap junctions within photobleached areas of cell-cell contact within 2 hrs. However, disruption of microfilaments with cytochalasin B inhibited the recruitment and assembly of both Cx26-YFP and Cx43-GFP into gap junctions within photobleached areas. Surprisingly, disruption of microtubules with nocodazole inhibited the recruitment of Cx43-GFP into gap junctions but had limited effect on the transport and clustering of Cx26-YFP into gap junctions within the photobleached regions of cell-cell contact. These results suggest that the recruitment of Cx43-GFP and Cx26-YFP to the cell surface or their lateral clustering into gap junctions plaques is dependent in part on the presence of intact actin microfilaments while Cx43-GFP was more dependent on intact microtubules than Cx26-YFP.
Actin Cytoskeleton↗
Axillary mass in a 20-year-old woman. Diagnosis: axillary accessory breast tissue.
Explore the source record for details and available documents.
Adult↗
Clustering of connexin 43-enhanced green fluorescent protein gap junction channels and functional coupling in living cells.
Communication-incompetent cell lines were transfected with connexin (Cx) 43 fused with enhanced green fluorescent protein (EGFP) to examine the relation between Cx distribution determined by fluorescence microscopy and electrical coupling measured at single-channel resolution in living cell pairs. Cx43-EGFP channel properties were like those of wild-type Cx43 except for reduced sensitivity to transjunctional voltage. Cx43-EGFP clustered into plaques at locations of cell-cell contact. Coupling was always absent in the absence of plaques and even in the presence of small plaques. Plaques exceeding several hundred channels always conferred coupling, but only a small fraction of channels were functional. These data indicate that clustering may be a requirement for opening of gap junction channels.
Animals↗
Sustained kilowatt lasing in a free-electron laser with same-cell energy recovery
Jefferson Laboratory's kW-level infrared free-electron laser utilizes a superconducting accelerator that recovers about 75% of the electron-beam power. In achieving first lasing, the accelerator operated "straight ahead" to deliver 38-MeV, 1.1-mA cw current for lasing near 5 &mgr;m. The waste beam was sent directly to a dump while producing stable operation at up to 311 W. Utilizing the recirculation loop to send the electron beam back to the linac for energy recovery, the machine has now recovered cw average currents up to 5 mA, and has lased cw with up to 1720 W output at 3.1 &mgr;m.
Journal Article↗
Evidence for allelic association of the dopamine beta-hydroxylase gene (DBH) with susceptibility to typical migraine.
Migraine is a debilitating neurological disorder characterized by recurrent attacks of severe headache. The disorder is highly prevalent, affecting approximately 12% of Caucasian populations. It is well known that migraine has a strong genetic component, although the type and number of genes involved is not yet clear. However, the calcium channel gene, CACNA1A, on chromosome 19 contains mutations responsible for familial hemiplegic migraine, a rare and severe subtype of migraine. There is also evidence to suggest that serotonin- and dopamine-related genes may be involved in the pathogenesis of migraine. This study employed a linkage and association approach to investigate neurotransmitter-related migraine candidate genes. Polymorphisms within the dopamine beta-hydroxylase (DBH) gene, serotonin transporter gene (SERT), and dopamine receptor gene (DRD2) were tested in 177 unrelated Caucasian migraineurs and 182 control individuals. In addition, an independent sample of 82 families affected with migraine was examined. Unrelated case-control association analysis of a DBH intragenic dinucleotide polymorphism indicated altered allelic distribution between migraine and control groups (chi2 = 16.53, P=0.019). Furthermore, the transmission/disequilibrium test, which was implemented on the family data, also indicated distortion of allele transmission for the same DBH marker (chi2 = 4.44, P=0.035). Together, these results provide evidence for allelic association of the DBH gene with typical migraine susceptibility (Fisher's combined P value =0.006) and indicate that further research into the role of the DBH gene in the etiology of migraine is warranted.
Alleles↗
A feline model of experimentally induced islet amyloidosis.
The study of the pathogenesis of islet amyloidosis and its relationship to the development and progression of type 2 diabetes mellitus has been hampered by the lack of an experimentally inducible animal model. The domestic cat, by virtue of the fact that it is one of the few species that spontaneously develop a form of diabetes mellitus that closely resembles human type 2 diabetes, including the formation of amyloid deposits derived from islet amyloid polypeptide (IAPP), was considered to be an excellent candidate species in which to attempt to develop a nontransgenic animal model for this disease process. To develop the model, 8 healthy domestic cats were given a 50% pancreatectomy, which was followed by treatment with growth hormone and dexamethasone. Once a stable diabetic state was established, cats were randomly assigned to groups treated with either glipizide or insulin at doses appropriate to control hyperglycemia. Cats were maintained on this treatment regimen for 18 months and then euthanized. Based on light microscopic examination of Congo red-stained sections of pancreas, all cats were negative for the presence of islet amyloid at the time of pancreatectomy. At the end of the study all 4 glipizide-treated cats had islet amyloid deposits, whereas only 1 of 4 insulin-treated cats had detectable amyloid. In addition, the glipizide treated cats had threefold higher basal and fivefold higher glucose-stimulated plasma IAPP concentrations than insulin-treated cats, suggesting an association between elevated IAPP secretion and islet amyloidosis. Blood-glycosylated hemoglobin concentrations were not significantly different between the two treatment groups. This study documents for the first time an inducible model of islet amyloidosis in a nontransgenic animal.
Amyloid↗
Researching limiting long-term illness.
Needs assessment has become one of the cornerstones for commissioning health care in the UK but, as yet, no agreed methodological framework exists. This study attempts to build on a number of different approaches used in needs assessment in order to formulate a more complex and integrated model. We have taken limiting long-term illness (LLI) as a starting point and examined its prevalence within the primary care setting in an area of North Staffordshire. This was followed by the application of a health status measure on two sub-samples (those reporting LLI and those not reporting LLI). The diagnostic assessments of the GP was placed alongside the results of the health status measure in order to compare self-assessment with the professional perspective. Finally, in-depth interviews with people with LLI were carried out examining their own experience of ill-health. We argue that this detailed and complex needs assessment allows for a more targeted approach to commissioning and service development.
Chronic Disease↗
The reliability of the three-dimensional FASTRAK measurement system in measuring cervical spine and shoulder range of motion in healthy subjects.
OBJECTIVES: To assess the inter-observer and intra-observer reliability of a new three-dimensional measurement system, the FASTRAK, in measuring cervical spine flexion/extension, lateral flexion and rotation and shoulder flexion/extension, abduction and external rotation in healthy subjects. METHODS: The study was conducted in two parts. One part assessed inter-observer reliability with two observers measuring 40 subjects. The other part assessed intra-observer reliability with one observer measuring 32 subjects on three occasions. All subjects had unrestricted, pain-free cervical spine and shoulder movement. Reliability was measured by the intraclass correlation coefficient [ICC(2,1)]. RESULTS: The inter-observer ICCs for the cervical spine ranged from 0.61 to 0.89 and for the shoulder from 0.68 to 0.75. After removal of outliers, all ICCs were above 0.70. Intra-observer ICCs for the cervical spine ranged from 0.54 to 0.82 and for the shoulder from 0.62 to 0.81. After removal of outliers, all ICCs were above 0.70 except for shoulder abduction (0.62). CONCLUSIONS: Whilst all movements measured by the FASTRAK showed good reliability, the reliability of the whole movement in a plane (e.g. left plus right lateral flexion) was better than for the separate movements (e.g. left and right lateral flexion taken separately). Inter-observer reliability was generally better than intra-observer reliability for most cervical spine movements, suggesting that variability of movement within subjects (e.g. over a period of days) for these movements was greater than variability between measures on the same occasion.
Adult↗
Chronic fatigue syndrome: sociodemographic subtypes in a community-based sample.
Most chronic fatigue syndrome (CFS) studies are based on information about patients from primary or tertiary care settings. These patients might not be typical of patients in the general population. This investigation involved examinations of individuals with CFS from a community-based study. A random sample of 18,675 in Chicago was interviewed by telephone. Individuals with chronic fatigue and at least four minor symptoms associated with CFS were given medical and psychiatric examinations. A group of physicians then diagnosed individuals with CFS, who were then subclassified based on three sociodemographic categories--gender, ethnicity, and work status. Sociodemographic subgroups were analyzed in terms of symptom severity, functional disability, coping, optimism, perceived stress, and psychiatric comorbidity. Women, minorities, and nonworking individuals with CFS reported greater levels of functional disability, symptom severity, and poorer psychosocial functioning than men, Caucasians, and working individuals, suggesting sociodemographic characteristics may be associated with poorer outcomes in urban, community-based samples of CFS individuals.
Adolescent↗
Small nodules detected on chest radiography: does size predict calcification?
STUDY OBJECTIVES: To determine whether the likelihood of lung nodule calcification can be predicted from nodule size as measured on a chest radiograph (CXR). DESIGN: Retrospective review of CXRs of patients with lung nodules < or =1 cm in size detected on CT scanning. CT images were used to identify calcifications and to provide spatial localization for readers to visualize nodules on a CXR and to measure their size. A subset of these nodules then was reexamined by different readers who did not view the CT scans SETTING: Two university hospitals (Albuquerque, NM; Dallas, TX) and a US Air Force/Veterans Administration medical center (Albuquerque, NM). PATIENTS: Two hundred thirty-six nodules in 185 patients RESULTS: One half of the nodules (118) seen on CT scans could not be located on CXR, of which 8 (7%) were calcified. The prevalence of calcifications in the other 118 nodules visualized on CXRs was much higher (71 of 118 nodules [60%]; p<0.005). Among the nodules visualized on CXRs, those < 7 mm in diameter (44 of 57 nodules [77%]) were more likely to be calcified than those > or = 7 mm in diameter (27 of 61 nodules [44%]; p<0.005). Radiographs of 42 of the smallest nodules visualized on CXRs by the initial readers later were examined prospectively by different readers who did not have access to the CT images. Thirty of 33 of the calcified nodules (91%) but only 3 of 9 of the noncalcified nodules (33%) were detected (p<0.005). These readers also recorded 40 additional small nodules that were not seen on CT scans, which were considered to be false-positives. CONCLUSIONS: Nodules detected on CXRs that measure <7 mm in size are likely to be calcified or to represent a false-positive finding.
Calcinosis↗
Trafficking, assembly, and function of a connexin43-green fluorescent protein chimera in live mammalian cells.
To examine the trafficking, assembly, and turnover of connexin43 (Cx43) in living cells, we used an enhanced red-shifted mutant of green fluorescent protein (GFP) to construct a Cx43-GFP chimera. When cDNA encoding Cx43-GFP was transfected into communication-competent normal rat kidney cells, Cx43-negative Madin-Darby canine kidney (MDCK) cells, or communication-deficient Neuro2A or HeLa cells, the fusion protein of predicted length was expressed, transported, and assembled into gap junctions that exhibited the classical pentalaminar profile. Dye transfer studies showed that Cx43-GFP formed functional gap junction channels when transfected into otherwise communication-deficient HeLa or Neuro2A cells. Live imaging of Cx43-GFP in MDCK cells revealed that many gap junction plaques remained relatively immobile, whereas others coalesced laterally within the plasma membrane. Time-lapse imaging of live MDCK cells also revealed that Cx43-GFP was transported via highly mobile transport intermediates that could be divided into two size classes of <0.5 microm and 0.5-1.5 microm. In some cases, the larger intracellular Cx43-GFP transport intermediates were observed to form from the internalization of gap junctions, whereas the smaller transport intermediates may represent other routes of trafficking to or from the plasma membrane. The localization of Cx43-GFP in two transport compartments suggests that the dynamic formation and turnover of connexins may involve at least two distinct pathways.
Animals↗
First day post-operative review following uncomplicated phacoemulsification.
PURPOSE: To determine whether the first day review is essential in management of patients following uncomplicated phacoemulsification with intraocular lens implantation. Patients are routinely seen on the day following surgery. This can produce logistical problems in patient attendance that can necessitate an overnight stay. If the first day review were abandoned this would lead to an increased uptake of day case surgery and a reduction in health care costs. METHODS: A retrospective cohort study was performed on all cases of uncomplicated phacoemulsification with intraocular lens implant surgery over a 6 month period. Slit lamp examination findings on the first post-operative day were reviewed. Visual acuity, corneal clarity, anterior chamber activity, intraocular pressure and configuration of the pupil were recorded. Any cases that failed to meet predetermined criteria underwent full case-note review. The subsequent management of these patients was analysed. RESULTS: Of the 201 cases of uncomplicated surgery, 74 cases (37%) failed to meet the study criteria and underwent review. Of these only 12 (6%) had their management altered as a result of the first day post-operative findings. This was entirely due to raised intraocular pressure. Visual acuity, corneal oedema and activity in the anterior chamber all improved on subsequent follow-up. CONCLUSIONS: The first day review of uncomplicated phacoemulsification with lens implant surgery provides the opportunity to treat raised intraocular pressure. A prospective randomised study is needed to identify means to prevent the post-operative intraocular pressure rise before we are able to consider abandoning the first review.
Ambulatory Surgical Procedures↗
Glaucoma screening by optometrists: positive predictive value of visual field testing.
PURPOSE: Visual field testing is increasingly being performed by optometrists in order to improve glaucoma detection. The aim of this study was to assess the positive predictive value (PPV) of visual field testing as currently practised by optometrists. METHODS: A retrospective study was performed of referrals for suspected glaucoma to an ophthalmology department during a 3 month period. The PPV for glaucoma was determined according to the reason for referral. RESULTS: There were 86 referrals for suspected glaucoma. Isolated field loss accounted for 12% of these referrals but no cases of glaucoma detection. These subjects were either false positive referrals or had field defects of nonglaucomatous aetiology (tilted optic disc and porencephalic cyst). The PPV for glaucoma among referrals with isolated field loss was significantly less than that among referrals with field loss in association with corroborative abnormalities (0 vs. 60%, p = 0.005). No such difference was found for referrals with raised intraocular pressure (43% vs. 57%, p = 0.38) or suspicious discs (25% vs. 53%, p = 0.60). CONCLUSIONS: Visual field testing is currently leading to unnecessary referrals to the hospital eye service with no detectable improvement in the accuracy of glaucoma suspect referrals. It is important that optometrists perform visual field testing in accordance with validated screening methodology.
Adult↗
Some biological actions of alkylglycerols from shark liver oil.
Shark liver oil has been used for over 40 years as both a therapeutic and preventive agent. The active ingredients in shark liver oil have been found to be a group of ether-linked glycerols known as alkylglycerols. Initial clinical use was for treating leukemias, and later to prevent radiation sickness from cancer x-ray therapy. Studies over the last 30 years have shown that alkylglycerols are multifunctional. The level of natural alkylglycerols rises within tumor cells, apparently in an effort to control cell growth. Recent studies indicate that the activation of protein kinase C, an essential step in cell proliferation, can be inhibited by alkylglycerols. This action suggests a competitive inhibition of 1.2-diacylglycerol by alkylglycerols. Further studies on the immunostimulatory action of alkylglycerols suggest a primary action on the macrophage. The process of macrophage activation has been demonstrated with both synthetic and natural alkylglycerols. While the exact mechanism has not been found, both an autocrine and paracrine system have been suggested. Shark liver is a major natural source of alkylglycerols, which have no known side effects in dosages of 100 mg three times a day. The information presented in this article suggests that alkylglycerols may be used both as an adjunct therapy in the treatment of neoplastic disorders and as an immune booster in infectious diseases.
Animals↗
Distinguishing hantavirus pulmonary syndrome from acute respiratory distress syndrome by chest radiography: are there different radiographic manifestations of increased alveolar permeability?
Hantavirus infection may cause diffuse air space disease, termed hantavirus pulmonary syndrome (HPS). The authors sought to determine if chest radiographs could differentiate HPS from typical acute respiratory distress syndrome (ARDS). The authors identified patients with either HPS (n = 11) or acute ARDS (n = 32) and selected the earliest chest radiograph showing diffuse airspace disease, and a chest radiograph taken 24 to 48 hours previously. Thoracic and general radiologists first viewed the chest radiograph showing diffuse air space disease, and ranked the likelihood that each case represented HPS versus ARDS. Afterward, readers viewed earlier chest radiographs and rescored each case. Receiver operating characteristic (ROC) curves from both scoring sessions were generated. The mean areas under the ROC curves for the entire group was 0.83 +/- 0.12 initially, and improved to 0.87 +/- 0.09 (p < 0.05) after viewing prior chest radiographs. Receiver operating characteristic curves of thoracic radiologists described greater areas than those of general radiologists both before and after viewing prior chest radiographs; 0.95 +/- 0.01 versus 0.78 +/- 0.08 (p < 0.05) and 96 +/- 0.02 versus 0.80 +/- 0.05 (p < 0.05). The mean sensitivity and specificity of chest radiograph interpretation for HPS was 86 +/- 13% and 74 +/- 11%, respectively. Chest radiographs can differentiate HPS from ARDS. Accuracy is improved by the use of serial radiographs and more highly trained readers. The chest radiograph findings may represent differences in the extent of alveolar epithelial damage seen in HPS and ARDS.
Acute Disease↗
Discharge planning for overseas patients.
Explore the source record for details and available documents.
Child↗