bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of herbal therapies by older, community‐dwelling women
Authors: Gözüm Sebahat , Ünsal Ayla
Published: March 2004

Background.  Herbal medicines, products and therapies are a subject of great public interest both nationally and worldwide. Use of herbal therapy is most common among women and patients with chronic health problems.

Aim.  This paper reports a study to determine the prevalence of herbal therapy use among women over 65 years who live independently in the community, and to compare the socio‐demographic characteristics and health status of older women who use herbal therapies and those who do not.

Methods.  This was a cross‐sectional study. Random samples of 385 older participants took part in structured interviews at five primary health care centres in Turkey between September and December 2002.

Results.  Herbal therapies were used by 48·3% of the sample in the previous 12 months. No differences in demographic characteristics were found for users and non‐users. We found that herbal therapy use was substantially higher among older women who: (1) reported any disability in activities of daily living, (2) had poor self‐reported health, (3) had very frequent physician visits, and (4) had chronic conditions such as cardiac problems, diabetes, stroke, cancer, asthma, pneumonia or urinary problems.

Conclusions.  It is important for community health nurses to be knowledgeable about the use of herbal therapies when providing care to older women because of possible interactions with other treatments, delays in seeking care, and poor quality products.
Dynamic cytoskeleton rearrangements in giant cells and syncytia of nematode‐infected roots
Authors: De Almeida Engler Janice , Van Poucke Kris , Karimi Mansour , De Groodt Ruth , Gheysen Greetje , Engler Gilbert , Gheysen Godelieve
Published: March 2004

Giant cells induced by root knot nematodes and syncytia caused by cyst nematodes are large multinucleated feeding cells containing a dense cytoplasm generated during a complex host–parasite association in plant roots. To find out whether cytoskeleton changes occurred during feeding cell development, transcriptional activity of actin (ACT) and tubulin genes and organization of the ACT filaments and of the microtubules (MTs) were analyzed in situ. The importance of changes in the cytoskeleton architecture for the proper initiation and development of galls and syncytia was demonstrated by perturbing the cytoskeleton with chemical inhibitors. The expression levels of cytoskeletal components, such as tubulins and ACTs, are proposed to be upregulated to allow the assembly of a new cytoskeleton in expanding feeding cells. However, MTs and ACT filaments failed to properly organize and appeared partially depolymerized throughout feeding site development. Both the actin and tubulin cytoskeletons were strongly disrupted in syncytia and mitotic figures were never observed. In contrast, in giant cells, an ACT and cortical MT cytokeleton, although disturbed, was still visible. In addition, a functional mitotic apparatus was present that contained multiple large spindles and arrested phragmoplasts, but no pre‐prophase bands. Chemical stabilization of the microtubular cytoskeleton with taxol blocked feeding site development. On the other hand, when the ACT or MT cytoskeleton of feeding cells was depolymerized by cytochalasin D or oryzalin, nematodes could complete their life cycle. Our data suggest that the cytoskeleton rearrangements and depolymerization induced by parasitic nematodes may be essential for a successful feeding process.
Interallelic complementation at the Arabidopsis CRE1 locus uncovers independent pathways for the proliferation of vascular initials and canonical cytokinin signalling
Authors: De León Berenice García‐Ponce , Zorrilla Jose Manuel Franco , Rubio Vicente , Dahiya Preeti , Paz‐Ares Javier , Leyva Antonio
Published: March 2004

The differentiation of vascular tissue plays a central role in root architecture and its functionality. Regardless of its importance, the molecular mechanisms involved in the inception of vascular morphogenesis and their interaction with hormones are only now beginning to be understood. The characterisation of the WOODEN LEG (wol/cre1 mutant), impaired in procambial cell proliferation and the identification of WOL/CRE1 as a cytokinin receptor, provided the first genetic evidence pointing to a role of cytokinins in the formation of vascular initials. However, the striking wol phenotype in vascular differentiation is unique among all the available cre1 alleles collection. In this work, we identified a mutant with identical deficiencies in vascular differentiation as wol. Complementation analysis revealed that this mutant rescued the wol short‐root phenotype. However, genetic characterisation of the mutant showed that the mutation was located at the CRE1 locus, indicating that both alleles displayed interallelic complementation. Trans‐heterozygotes characterisation showed that these plants fully restored the deficiency in vascular differentiation but not the canonical cytokinin signalling. Furthermore, we show that, as measured in root growth inhibition, calli regeneration assays and northern analysis, the original wol allele is in fact more sensitive to cytokinins than the trans‐heterozygous plants, or some cre1 alleles showing wild‐type vascular morphogenesis. Thus, there is no strict correlation between the phenotype in vascular differentiation displayed by the cre1/wol alleles and canonical cytokinin signalling. These results indicate that at least partially independent regulatory circuits may operate in procambial cell proliferation and in cytokinin responsiveness exerted through the CRE1 receptor.
Capturing the power of academic medicine to enhance health and health care of the elderly in the USA
Authors: Hazzard William R
Published: March 2004

As in Japan, the US population is aging progressively, a trend that will challenge the health‐care system to provide for the chronic, multiple and complex needs of its elderly citizens. and as in Japan, the US academic health enterprise has only belatedly mounted a response to that challenge. Herein is reviewed a quarter of a century of the author's personal experience in developing new programs in gerontology and geriatric medicine from a base in the Department of Internal Medicine at three US academic health centers (AHC): The University of Washington (as Division Head), Johns Hopkins University (as Vice‐Chair), and Wake Forest University (as Chair). Rather than to build a program from a new department of geriatrics, this strategy was chosen to capture the power and resources of the department of internal medicine, the largest university department, to ‘gerontologize’ the institution, beginning with general internal medicine and all of the medical subspecialties (the approach also chosen to date at all but a handful of US AHC). The keystone of success at each institution has been careful faculty development through fellowship training in clinical geriatrics, education and research. Over the same interval major national progress has occurred, including expanded research and training at the National Institute on Aging and the Department of Veterans Affairs, and accreditation of more than 100 fellowship programs for training and certification of geriatricians. However, less than 1% of US medical graduates elect to pursue such training. Hence such geriatricians will remain concentrated at AHC, and most future geriatric care in the USA will be provided by a broad array of specialists, who will be educated and trained in geriatrics by these academic geriatricians.
John Colet and a Lost Manuscript of 1506
Authors: Arnold Jonathan
Published: March 2004

John Colet, the humanist, attempted clerical reform early in his tenure as Dean of St Paul's (1505–19), by reminding certain members of the cathedral personnel of the existing statutes and by seeking to impose some visitation injunctions upon them. A 1506 manuscript, containing details of these efforts, is now lost. This article examines the contents of the manuscript, which are known from a nineteenth‐century transcription, and investigates the minor clergy, whom it concerned. It also discusses the possible whereabouts of the original manuscript; Colet's possible motivation for writing the proposals; the reaction to Colet's ideas; and how his clerical colleagues perceived Colet. The article concludes that Colet's inappropriate approach to reform hindered his success.
How to Put the Community in Community‐Based Justice: Some Views of Participants in Criminal Court Diversion
Authors: Landau Tammy
Published: March 2004

Abstract: Two post‐charge criminal court diversion projects were recently launched in Toronto, Canada. Individuals charged with criminal offences who meet strict criteria are diverted from the criminal process in exchange for performing a community sanction. Under this model, direct community involvement is critical to ‘success’. This study is an evaluation of these projects, combining file data with the results of interviews with the main participants. Results suggest that the projects are highly successful, and that involved communities are highly supportive of the current form and structure of post‐charge diversion.
Anti‐Social Behaviour, Crime Control and Social Control
Authors: Brown Alison P.
Published: March 2004

Abstract: Measures introduced to tackle anti‐social behaviour have been described as crime control through the coming together of social housing management and policing. This suggests that a new form of social control is coming into effect. Taking Cohen's classic analysis of social control, it is possible to discern the extent to which the control of anti‐social behaviour is characterised by a blurring of boundaries, behaviourism, mesh‐thinning and net‐widening. This leads to a discussion of the inclusionary and exclusionary aspects of anti‐social behaviour as a phenomenon which is linked to the changing constellation of ‘care and control’ professions.
Molecular response to climate change: temperature dependence of UV‐induced DNA damage and repair in the freshwater crustacean Daphnia pulicaria
Authors: MacFadyen Emily J. , Williamson Craig E. , Grad Gabriella , Lowery Megan , Jeffrey Wade H. , Mitchell David L.
Published: March 2004

In temperate lakes, asynchronous cycles in surface water temperatures and incident ultraviolet (UV) radiation expose aquatic organisms to damaging UV radiation at different temperatures. The enzyme systems that repair UV‐induced DNA damage are temperature dependent, and thus potentially less effective at repairing DNA damage at lower temperatures. This hypothesis was tested by examining the levels of UV‐induced DNA damage in the freshwater crustacean Daphnia pulicaria in the presence and absence of longer‐wavelength photoreactivating radiation (PRR) that induces photoenzymatic repair (PER) of DNA damage. By exposing both live and dead (freeze‐killed) Daphnia as well as raw DNA to UV‐B in the presence and absence of PRR, we were able to estimate the relative importance and temperature dependence of PER (light repair), nucleotide excision repair (NER, dark repair), and photoprotection (PP). Total DNA damage increased with increasing temperature. However, the even greater increase in DNA repair rates at higher temperatures led net DNA damage (total DNA damage minus repair) to be greater at lower temperatures. Photoprotection accounted for a much greater proportion of the reduction in DNA damage than did repair. Experiments that looked at survival rates following UV exposure demonstrated that PER increased survival rates. The important implication is that aquatic organisms that depend heavily on DNA repair processes may be less able to survive high UV exposure in low temperature environments. Photoprotection may be more effective under the low temperature, high UV conditions such as are found in early spring or at high elevations.
Medical and Cognitive Correlates of Denture Wearing in Older Community‐Dwelling Adults
Authors: Weyant Robert J. , Pandav Rajesh S. , Plowman Judith L. , Ganguli Mary
Published: March 2004

Objectives: To examine the association between denture wearing and use of dental services, oral function limitations, and medical and cognitive status in a community‐based cohort of rural older adults enrolled in an epidemiological study.

Design: This cross‐sectional study was part of a larger cohort study, the Monongahela Valley Independent Elders Survey. Dental data were collected during the fifth wave of assessments (10 years after the start of the study in 1987).

Setting: Monongahela Valley, a rural western Pennsylvania community.

Participants: The 805 participants were English‐speaking community‐dwelling (noninstitutionalized) persons, aged 73 and older, with at least a sixth grade education.

Measurements: A questionnaire was used to collect data on denture‐wearing status, oral function limitations, and recency of the last dental visit. Other data collected included demographics, self‐rated health, medication usage, depression, cognitive status using the Mini‐Mental State Examination, and self‐reports of weight loss and appetite.

Results: There were 44.7% of participants who had full dentures. Those with complete dentures were more likely to complain of oral function limitation, report poor health status, and take prescription medications. Additionally, 93.6% of those with complete dentures had not seen a dentist in more than 1 year.

Conclusion: Denture wearing and edentulism are common in older patients and can be related to poor quality of life and risk for undiagnosed oral disease and may be a marker for other medical comorbidities. Geriatricians need to include oral health status evaluations and understand that attention to the oral cavity should be part of an older adult's care.
Who Are the Uninsured Elderly in the United States?
Authors: Mold James W. , Fryer George E. , Thomas Cynthia H.
Published: March 2004

Because of the Medicare program, a common assumption is made that virtually all older Americans have health insurance coverage. Data from the 2000 National Health Interview Survey were analyzed to estimate the number of people aged 65 and older without health insurance; their stated reasons for being uninsured; and the associations between lack of insurance and sociodemographic variables, health status, and access to and use of healthcare services.

In 2000, there were approximately 350,000 older Americans with no health insurance. Those without insurance were more likely to be younger, Hispanic, nonwhite, unmarried (widowed, divorced, or never married), poor, and foreign‐born. They were less likely to hold U.S. citizenship. Despite relatively high rates of chronic medical conditions, they were unlikely to receive outpatient or home healthcare services. The most common reason given for lack of insurance was its cost.

This study reveals important gaps in the availability of health insurance for the elderly, gaps that are likely to affect an increasing number of older Americans in the coming decade.
Neuron‐specific enolase‐producing leiomyosarcoma of the mesentery
Authors: FUKUNAGA MASAHARU
Published: March 2004

A case of neuron‐specific enolase (NSE)‐producing leiomyosarcoma arising in the mesentery of a 62‐year‐old female is presented. Preoperatively, serum level of NSE was markedly elevated. A well‐defined but unencapsulated tumor measuring 14×12×9 cm was histologically characterized by a fascicular or herring‐bone arrangement of atypical spindle or oval tumor cells with vesicular cigar‐shaped nuclei, inconspicuous nucleoli and abundant clear to brightly eosinophilic cytoplasm. Immunohistochemically, the tumor was positive for vimentin, α‐smooth muscle actin, muscle actin, desmin, and γ‐NSE. Postoperatively, serum level of NSE decreased to within normal range. The NSE levels were, however, elevated again as metastatic lesions in the liver had enlarged. The patient died of the liver metastases 10 months after surgery. Serum NSE level can be a useful index of tumor extent and for monitoring treatment of some patients with leiomyosarcoma.
Microsatellite analysis of urine sediment versus urine cytology for diagnosing transitional cell tumors of the urinary bladder
Authors: FORNARI DELFINA , STEVEN KENNETH , HANSEN ALASTAIR B. , VIBITS HENRIK , JEPSEN JAN V. , POULSEN ASGER L. , SCHWARTZ MARIANNE , HORN THOMAS
Published: March 2004

The aim was to evaluate microsatellite analysis of urine sediment (MAUS) as an alternative method to urine cytology for routine diagnosis of patients with transitional cell tumors (TCT) of the urinary bladder. Urine cytology has the advantage of being non‐invasive, fast and cheap, but is of limited value because of its low sensitivity. MAUS has previously been found to be a successful alternative method. However, the experimental set‐up of such investigations implied exclusion of samples with unfavorable characteristics and use of a large number of markers. In the present study, MAUS was tested on all samples routinely available and a small panel of markers was selected. The urine sediments of 66 TCT patients and 24 controls were analyzed by MAUS with 16 fluorescent markers and by urine cytology. All samples were analyzed, including the ones of later micturition, with gross hematuria, leukocyturia or absence of visible sediment. In patients with tumors of low grade (grades I–II), MAUS was significantly more sensitive than urine cytology. The two methods were of equivalent diagnostic power in high‐grade (grades III–IV), high‐stage (pT1‐pT4) tumors. A panel of the six most informative markers for MAUS was selected. Although MAUS has an advantage over routine cytology in low‐grade, low‐stage tumors, an overall sensitivity of 45% is not sufficient for routine clinical use.
The binding of proteinase 3 antineutrophil cytoplasmic antibodies (PR3-ANCA) varies in different ELISAs
Authors: Trevisin M , Neeson P , Savige J
Published: March 2004

Background:The demonstration of proteinase 3 specific antineutrophil cytoplasmic antibodies (PR3-ANCA), and the estimation of antibody values are useful in the diagnosis and management of patients with Wegener’s granulomatosis (WG). However, external quality assessment programmes suggest that PR3-ANCA binding varies in different assays.

Aim:To demonstrate variations in PR3-ANCA binding in different commercial and in house enzyme linked immunosorbent assays (ELISAs).

Method:Binding of a PR3-ANCA standard and 19 sera from patients with WG was compared in eight commercial and in house assays. Binding was expressed in different units depending on the kit.

Results:One commercial assay performed unsatisfactorily. Three commercial kits produced PR3-ANCA binding (70, 102, and 84 U/ml) close to the expected value for the standard (100 U/ml). Serial dilutions of this standard were linear in only one commercial assay and the in house assay. Sera from patients with WG with borderline binding in the in house assay bound in the eight commercial kits at 0–148 kit units; low binding sera ranged from 0 to 273 units; moderately strong sera bound at 7–260 units; and strongly binding sera bound at 13–336 units. In four assays, at least one strongly positive serum bound at levels greater than the provided range.

Conclusions:Levels of antibody binding and units of binding have not been standardised in commercially available PR3-ANCA ELISAs. This may affect the diagnosis and management of patients with WG, in addition to the implementation of international guidelines for treatment.
Does histopathological examination of breast reduction specimens affect patient management and clinical follow up?
Authors: Cook I S , Fuller C E
Published: March 2004

Aim:To assess the value of the histopathological examination of routine breast reduction specimens.

Methods:All patients who underwent breast reduction surgery over a 10 year period were identified. The histopathology report for each patient was analysed. For all cases with important microscopic abnormalities, the patient’s medical notes were examined to identify whether clinical follow up was arranged.

Results:Histopathology reports for specimens from 1289 patients were examined. One thousand, two hundred and fifty eight of these specimens (97.6%) were reported microscopically as showing normal breast tissue or benign breast disease, 26 cases (2.0%) showed lesions of uncertain malignant potential, four cases (0.3%) showed ductal carcinoma in situ (DCIS) or microinvasive malignancy, and there was one case (0.1%) of invasive malignancy. Important diagnoses were made in 2.1% of cases with no macroscopic abnormality. Clinical follow up was arranged for all patients with a diagnosis of DCIS, microinvasive carcinoma, or invasive malignancy. There were 26 patients diagnosed with lesions of uncertain malignant potential; 11 had follow up arrangements made and 13 patients were discharged. Follow up data was not available for two patients.

Conclusions:Histopathological examination of breast reduction specimens may reveal important pathological diagnoses. In some cases, patients were discharged from medical care despite histopathological examination revealing lesions associated with an increased risk of developing breast carcinoma.
Clinical evaluation of the polymerase chain reaction for the rapid diagnosis of tuberculosis
Authors: Cheng V C C , Yam W C , Hung I F N , Woo P C Y , Lau S K P , Tang B S F , Yuen K Y
Published: March 2004

Aims:Use of the polymerase chain reaction for the detection ofMycobacterium tuberculosis(TB PCR) as a basis for making clinical decisions on the initiation of antituberculosis treatment was studied.

Methods:A retrospective study involving a cohort of 155 patients being investigated for tuberculosis in an infectious disease consultation service was undertaken. TB PCR was performed on pulmonary and extrapulmonary specimens from these patients. The sensitivity of TB PCR was analysed.

Results:Of the 155 patients, 144 fitted the clinical diagnosis of tuberculosis, and 112 of them were culture positive forM tuberculosis. Sixty (58.3%) patients with clinical features suggestive of tuberculosis received antituberculosis treatment based on positive TB PCR alone. Of 224 clinical specimens (138 pulmonary and 86 extrapulmonary) sent for TB PCR, 148 (99 pulmonary and 49 extrapulmonary) were positive in 117 patients. Of the 690 clinical specimens sent for culture, 279 were positive forM tuberculosisin 112 patients. The diagnostic sensitivity of TB PCR was 75.9% (85 of 112) and 81.3% (117 of 144) in patients with culture confirmed and clinically diagnosed tuberculosis, respectively. Using culture as the gold standard, the overall sensitivity of TB PCR was 78.3%, and for pulmonary and extrapulmonary specimens it was 82.3% and 72.0%, respectively.

Conclusions:TB PCR is a rapid and reliable test in the diagnosis and management of tuberculosis.
A simple method for the prevention of endometrial autolysis in hysterectomy specimens
Authors: Houghton J P , Roddy S , Carroll S , McCluggage W G
Published: March 2004

Aims:Uteri are among the most common surgical pathology specimens. Assessment of the endometrium is often difficult because of pronounced tissue autolysis. This study describes a simple method to prevent endometrial autolysis and aid in interpretation of the endometrium.

Methods:Sixty uteri were injected with formalin using a needle and syringe directed alongside a probe, which was inserted through the external cervical os into the endometrial cavity. Injection was performed on the same day as removal of the uterus. As controls, 60 uteri that were not injected with formalin were examined. The degree of endometrial autolysis was assessed on a four point scale (0–3), with a score of 0 representing no or minimal autolysis and a score of 3 representing extensive autolysis, such that histological interpretation of the endometrium was impossible.

Results:In the injected group, the number of cases with scores of 0, 1, 2, and 3 was 42, 13, four, and one, respectively. The corresponding values for the control group were 17, 23, eight, and 12, respectively. This was highly significant (p < 0.001)

Conclusions:There was significantly less endometrial autolysis in uteri injected with formalin. The use of this simple procedure should be encouraged in hysterectomy specimens.
My Father
Authors: Dirac Monica
Published: March 2004

As all of those present who knew my father will remember that he was a very shy man and he always avoided interviews with the press. He refused to talk to reporters and avoided having his photograph taken when ever possible. I think that this is probably why so many published accounts of his life failed to capture his personal side, especially one published in the last decade by the Scientific American. For this reason, I am happy to have the opportunity to share with you some of my memories of him, and to try and put the record straight.
Dirac's Footsteps and Supersymmetry
Authors: Ramond Pierre
Published: March 2004

One hundred years after its creator's birth, the Dirac equation stands as the cornerstone of XXth Century physics. But it is much more, as it carries the seeds of supersymmetry. Dirac also invented the light-cone, or "front form" dynamics, which plays a crucial role in string theory and in elucidating the finiteness of N=4 Yang-Mills theory. The light-cone structure of eleven-dimensional supergravity (N=8 supergravity in four dimensions) suggests a group-theoretical interpretation of its divergences. We speculate they could be compensated by an infinite number of triplets of massless higher spin fields, each obeying a Dirac-like equation associated with the coset F4/SO(9). The divergences are proportional to the trace over a non-compact structure containing the compact form of F4. Its nature is still unknown, but it could show the way to M-theory.
TRPC4 forms store-operated Ca2+ channels in mouse mesangial cells
Authors: Wang Xiaoxia , Pluznick Jennifer L. , Wei Peilin , Padanilam Babu J. , Sansom Steven C.
Published: March 2004

Studies were performed to identify the molecular component responsible for store-operated Ca2+ entry in murine mesangial cells (MMC). Because the canonical transient receptor potential (TRPC) family of proteins was previously shown to comprise Ca2+-selective and -nonselective cation channels in a variety of cells, we screened TRPC1–TRPC7 with the use of molecular methods and the fura 2 method to determine their participation as components of the mesangial store-operated Ca2+ (SOC) channel. Using TRPC-specific primers and RT-PCR, we found that cultured MMC contained mRNA for TRPC1 and TRPC4 but not for TRPC2, TRPC3, TRPC5, TRPC6, and TRPC7. Immunocytochemical staining of MMC revealed predominantly cytoplasmic expression of TRPC1 and plasmalemmal expression of TRPC4. The role of TRPC4 in SOC was determined with TRPC4 antisense and fura 2 ratiometric measurements of intracellular Ca2+ concentration ([Ca2+]i). SOC was measured as the increase in [Ca2+]i after extracellular Ca2+ was increased from <10 nM to 1 mM in the continued presence of thapsigargin. We found that TRPC4 antisense, which reduced plasmalemmal expression of TRPC4, inhibited SOC by 83%. Incubation with scrambled TRPC4 oligonucleotides did not affect SOC. Immunohistochemical staining identified expressed TRPC4 in the glomeruli of mouse renal sections. The results of RT-PCR performed to distinguish between TRPC4-α and TRPC4-β were consistent with expression of both isoforms in brain but with only TRPC4-α expression in MMC. These studies show that TRPC4-α may form the homotetrameric SOC in mouse mesangial cells.
RhoA, Rac1, and Cdc42 exert distinct effects on epithelial barrier via selective structural and biochemical modulation of junctional proteins and F-actin
Authors: Bruewer Matthias , Hopkins Ann M. , Hobert Michael E. , Nusrat Asma , Madara James L.
Published: March 2004

Epithelial intercellular junctions regulate cell-cell contact and mucosal barrier function. Both tight junctions (TJs) and adherens junctions (AJs) are regulated in part by their affiliation with the F-actin cytoskeleton. The cytoskeleton in turn is influenced by Rho family small GTPases such as RhoA, Rac1, and Cdc42, all of which constitute eukaryotic targets for several pathogenic organisms. With a tetracycline-repressible system to achieve regulated expression in Madin-Darby canine kidney (MDCK) epithelial cells, we used dominant-negative (DN) and constitutively active (CA) forms of RhoA, Rac1, and Cdc42 as tools to evaluate the precise contribution of each GTPase to epithelial structure and barrier function. All mutant GTPases induced time-dependent disruptions in epithelial gate function and distinct morphological alterations in apical and basal F-actin pools. TJ proteins occludin, ZO-1, claudin-1, claudin-2, and junctional adhesion molecule (JAM)-1 were dramatically redistributed in the presence of CA RhoA or CA Cdc42, whereas only claudins-1 and -2 were redistributed in response to CA Rac1. DN Rac1 expression also induced selective redistribution of claudins-1 and -2 in addition to JAM-1, whereas DN Cdc42 influenced only claudin-2 and DN RhoA had no effect. AJ protein localization was unaffected by any mutant GTPase, but DN Rac1 induced a reduction in E-cadherin detergent solubility. All CA GTPases increased the detergent solubility of claudins-1 and -2, but CA RhoA alone reduced claudin-2 and ZO-1 partitioning to detergent-insoluble membrane rafts. We conclude that Rho family GTPases regulate epithelial intercellular junctions via distinct morphological and biochemical mechanisms and that perturbations in barrier function reflect any imbalance in active/resting GTPase levels rather than simply loss or gain of GTPase activity.
Calcineurin is required for translational control of protein synthesis in rat pancreatic acini
Authors: Sans Maria Dolors , Williams John A.
Published: March 2004

CCK increases the rate of net protein synthesis in rat pancreatic acini by activating initiation and elongation factors required for translation. The immunosuppressant FK506 inhibits the Ca2+-calmodulin-dependent phosphatase calcineurin in pancreatic acinar cells and blocks pancreatic growth induced by chronic CCK treatment. To test a requirement for calcineurin in the activation of the translational machinery stimulated by CCK, we evaluated the effects of FK506 on protein synthesis and on regulatory initiation and elongation factors in rat pancreatic acini in vitro. CCK acutely increased protein synthesis in acini from normal rats with a maximum increase at 100 pM CCK to 170 ± 11% of control. The immunosuppressant FK506 dose-dependently inhibited CCK-stimulated protein synthesis over the same concentration range that blocked calcineurin activity, as assessed by dephosphorylation of the calcineurin substrate calcium-regulated heat-stable protein of 24 kDa. Another immunosuppressant, cyclosporin A, inhibited protein synthesis, but its effects appeared more complex. FK506 also inhibited protein synthesis stimulated by bombesin and carbachol. FK506 did not significantly affect the activity of the initiation factor-2B, or the phosphorylation of the initiation factor-2α, ribosomal protein protein S6, or the mRNA cap binding protein eukaryotic initiation factor (eIF) 4E. Instead, blockade of calcineurin with FK506 reduced the phosphorylation of the eIF4E binding protein, reduced the formation of the eIF4F complex, and increased the phosphorylation of eukaryotic elongation factor 2. From these results, we conclude that calcineurin activity is required for protein synthesis, and this action may be related to an effect on the formation of the mRNA cap binding complex and the elongation processes.
Ablation of calcitonin/calcitonin gene-related peptide-α impairs fetal magnesium but not calcium homeostasis
Authors: McDonald Kirsten R. , Fudge Neva J. , Woodrow Janine P. , Friel James K. , Hoff Ana O. , Gagel Robert F. , Kovacs Christopher S.
Published: March 2004

We used the calcitonin/calcitonin gene-related peptide (CGRP)-α gene knockout model ( Ct/Cgrp null) to determine whether calcitonin and CGRPα are required for normal fetal mineral homeostasis and placental calcium transfer. Heterozygous ( Ct/Cgrp+/−) and Ct/Cgrp null females were mated to Ct/Cgrp+/−males. One or two days before term, blood was collected from mothers and fetuses and analyzed for ionized Ca, Mg, P, parathyroid hormone (PTH), and calcitonin. Amniotic fluid was collected for Ca, Mg, and P. To quantify skeletal mineral content, fetuses were reduced to ash, dissolved in nitric acid, and analyzed by atomic absorption spectroscopy for total Ca and Mg. Placental transfer of45Ca at 5 min was assessed. Ct/Cgrp null mothers had significantly fewer viable fetuses in utero compared with Ct/Cgrp+/−and wild-type mothers. Fetal serum Ca, P, and PTH did not differ by genotype, but serum Mg was significantly reduced in null fetuses. Placental transfer of45Ca at 5 min was normal. The calcium content of the fetal skeleton was normal; however, total Mg content was reduced in Ct/Cgrp null skeletons obtained from Ct/Cgrp null mothers. In summary, maternal absence of calcitonin and CGRPα reduced the number of viable fetuses. Fetal absence of calcitonin and CGRPα selectively reduced serum and skeletal magnesium content but did not alter ionized calcium, placental calcium transfer, and skeletal calcium content. These findings indicate that calcitonin and CGRPα are not needed for normal fetal calcium metabolism but may regulate aspects of fetal Mg metabolism.
Assessment of the function of the βC-subunit of activin in cultured hepatocytes
Authors: Wada Wataru , Maeshima Akito , Zhang You-Qing , Hasegawa Yoshihisa , Kuwano Hiroyuki , Kojima Itaru
Published: March 2004

We assessed the function of the βC-subunit of activin in hepatocytes. We studied the effect of conditioned medium of Chinese hamster ovary (CHO) cell line stably expressing the βC gene (CHO-βC) on growth of AML12 hepatocytes. We also examined the effect of recombinant activin C and transfection of the βC gene by using adenovirus vector. CHO-βC secreted activin C, a homodimer of the βC, as well as precursors of the βC. The conditioned medium of CHO-βC increased both [3H]thymidine incorporation and the cell number in AML12 cells. It also supported survival of AML12 cells in a serum-free condition. Recombinant human activin C also increased both [3H]thymidine incorporation and the number of AML12 cells. Transfection of AML12 cells with the βC-subunit led to the stimulation of [3H]thymidine incorporation. Analysis of the conditioned medium revealed that the βC-subunit formed a heterodimer with the endogenous βA, the formation of which was dependent on the amount of βC expressed. Recombinant activin C did not affect the binding of 125I-activin A to its receptor or follistatin. These results indicate that activin C stimulates growth of AML12 cells. The βC-subunit modifies the function of the βA-subunit by multiple mechanisms.
Plasma ghrelin levels and hunger scores in humans initiating meals voluntarily without time- and food-related cues
Authors: Cummings D. E. , Frayo R. Scott , Marmonier Corinne , Aubert Roberte , Chapelot Didier
Published: March 2004

Ghrelin is an orexigenic hormone that is implicated in meal initiation, in part because circulating levels rise before meals. Because previous human studies have examined subjects fed on known schedules, the observed preprandial ghrelin increases could have been a secondary consequence of meal anticipation. A causal role for ghrelin in meal initiation would be better supported if preprandial increases occurred before spontaneously initiated meals not prompted by external cues. We measured plasma ghrelin levels among human subjects initiating meals voluntarily without cues related to time or food. Samples were drawn every 5 min between a scheduled lunch and a freely requested dinner, and hunger scores were obtained using visual analog scales. Insulin, glucose, fatty acids, leptin, and triglycerides were also measured. Ghrelin levels decreased shortly after the first meal in all subjects. A subsequent preprandial increase occurred over a wide range of intermeal intervals (IMI; 320–425 min) in all but one subject. Hunger scores and ghrelin levels showed similar temporal profiles and similar relative differences in magnitude between lunch and dinner. One subject displayed no preprandial ghrelin increase and was also the only individual whose insulin levels did not return to baseline between meals. This finding, along with a correlation between area-under-the-curve values of ghrelin and insulin, suggests a role for insulin in ghrelin regulation. The preprandial increase of ghrelin levels that we observed among humans initiating meals voluntarily, without time- or food-related cues, and the overlap between these levels and hunger scores are consistent with a role for ghrelin in meal initiation.
Bax interacts with the voltage-dependent anion channel and mediates ethanol-induced apoptosis in rat hepatocytes
Authors: Adachi Masayuki , Higuchi Hajime , Miura Soichiro , Azuma Toshifumi , Inokuchi Sayaka , Saito Hidetsugu , Kato Shinzo , Ishii Hiromasa
Published: March 2004

Acute ethanol exposure induces oxidative stress and apoptosis in primary rat hepatocytes. Previous data indicate that the mitochondrial permeability transition (MPT) is essential for ethanol-induced apoptosis. However, the mechanism by which ethanol induces the MPT remains unclear. In this study, we investigated the role of Bax, a proapoptotic Bcl-2 family protein, in acute ethanol-induced hepatocyte apoptosis. We found that Bax translocates from the cytosol to mitochondria before mitochondrial cytochrome c release. Bax translocation was oxidative stress dependent. Mitochondrial Bax formed a protein complex with the mitochondrial voltage-dependent anion channel (VDAC). Prevention of Bax-VDAC interactions by a microinjection of anti-VDAC antibody effectively prevented hepatocyte apoptosis by ethanol. In conclusion, these data suggest that Bax translocation from the cytosol to mitochondria leads to the subsequent formation of a Bax-VDAC complex that plays a crucial role in acute ethanol-induced hepatocyte apoptosis.
Diversity of voltage-dependent K+channels in human pulmonary artery smooth muscle cells
Authors: Platoshyn Oleksandr , Remillard Carmelle V. , Fantozzi Ivana , Mandegar Mehran , Sison Tiffany T. , Zhang Shen , Burg Elyssa , Yuan Jason X.-J.
Published: March 2004

Electrical excitability, which plays an important role in excitation-contraction coupling in the pulmonary vasculature, is regulated by transmembrane ion flux in pulmonary artery smooth muscle cells (PASMC). This study examined the heterogeneous nature of native voltage-dependent K+channels in human PASMC. Both voltage-gated K+(KV) currents and Ca2+-activated K+(KCa) currents were observed and characterized. In cell-attached patches of PASMC bathed in Ca2+-containing solutions, depolarization elicited a wide range of K+unitary conductances (6–290 pS). When cells were dialyzed with Ca2+-free and K+-containing solutions, depolarization elicited four components of KVcurrents in PASMC based on the kinetics of current activation and inactivation. Using RT-PCR, we detected transcripts of 1) 22 KVchannel α-subunits (KV1.1–1.7, KV1.10, KV2.1, KV3.1, KV3.3–3.4, KV4.1–4.2, KV5.1, KV6.1–6.3, KV9.1, KV9.3, KV10.1, and KV11.1), 2) three KVchannel β-subunits (KVβ1–3), 3) four KCachannel α-subunits ( Slo-α1 and SK2–SK4), and 4) four KCachannel β-subunits (KCaβ1–4). Our results show that human PASMC exhibit a variety of voltage-dependent K+currents with variable kinetics and conductances, which may result from various unique combinations of α- and β-subunits forming the native channels. Functional expression of these channels plays a critical role in the regulation of membrane potential, cytoplasmic Ca2+, and pulmonary vasomotor tone.
Expression of NPY Y1and Y5receptors in the hypothalamic paraventricular nucleus of aged Fischer 344 rats
Authors: Coppola Jessica D. , Horwitz Barbara A. , Hamilton Jock , McDonald Roger B.
Published: March 2004

Many mammals, nearing the end of life, spontaneously decrease their food intake and body weight, a stage we refer to as senescence. The spontaneous decrease in food intake and body weight is associated with attenuated responses to intracerebroventricular injections of neuropeptide Y (NPY) compared with old presenescent or with young adult rats. In the present study, we tested the hypothesis that this blunted responsiveness involves the number and expression of hypothalamic paraventricular nucleus (PVN) Y1and/or Y5NPY receptors, both of which are thought to mediate NPY-induced food intake. We found no significant difference in mRNA levels, via quantitative PCR, for Y1and Y5receptors in the PVN of senescent vs. presenescent rats. In contrast, immunohistochemistry indicated that the number of PVN neurons staining for Y1receptor protein was greater in presenescent compared with senescent rats. We conclude that a decreased expression and number of Y1or Y5receptors in the PVN cannot explain the attenuated responsiveness of the senescent rats to exogenous NPY.
Immunolocalization of protein kinase C isoenzymes α, βI, βII, δ, and ε in mouse kidney
Authors: Redling Stephanie , Pfaff Imke L. , Leitges Michael , Vallon Volker
Published: March 2004

Localization of protein kinase C (PKC) isoenzymes α, βI, βII, δ, and ε was studied employing Western blot analysis and immunohistochemical methods including confocal laser-scanning microscopy in the kidney of two mice strains, namely, C57BL/6 and 129/Sv, which have recently been used as genetic backgrounds for respective knockout mice. Immunoblot analysis identified immunoreactive bands for each isoenzyme in total kidney cell extracts. Isoenzyme expression sites were identical for both strains. Glomeruli expressed PKC-α, -βI, and -ε. The latter isoenzme was also detected in apical aspects of proximal convoluted but not in proximal straight tubules. In contrast to rats, neither PKC-α nor PKC-βI was detectable in the proximal tubule. Immunofluorescence was observed in luminal membranes of medullary (MTAL) and cortical thick ascending limbs for PKC-βI and in MTAL for PKC-ε. The cortical collecting duct expressed PKC-α, -βI, and -δ in intercalated cells only. In the outer medullary collecting duct, PKC-α and -βI were detectable in principal cells, whereas PKC-δ was found in intercalated cells. In the inner medullary collecting duct, PKC-α, -βI, and -βII were detected. As described for the rat, the expression of PKC-βII was otherwise restricted to cortical and medullary interstitial cells. The specificity of all labeling was confirmed in respective PKC isoenzyme knockout mice. In summary, distinct expression patterns were shown for PKC isoenzymes α, βI, βII, δ, and ε in the mouse kidney.
Evidence for a role of protein kinase C-α in urine concentration
Authors: Yao Lijun , Huang Dan-Yang , Pfaff Imke L. , Nie Xin , Leitges Michael , Vallon Volker
Published: March 2004

In mouse kidney, the conventional protein kinase C (PKC) isoenzyme α is expressed in glomeruli, the cortical collecting duct (intercalated cells only), and medullary collecting duct. To get insights on its function, PKC-α knockout (−/−) and wild-type (+/+) mice were studied. When provided free access to water, PKC-α −/− mice showed ∼50% greater urine flow rate and lower urinary osmolality in 24-h metabolic cage experiments despite a greater urinary vasopressin-to-creatinine ratio vs. PKC-α +/+ mice. Renal albumin excretion was not different. Clearance experiments under inactin/ketamine anesthesia revealed a modestly reduced glomerular filtration rate and showed a reduced absolute and fractional renal fluid reabsorption in PKC-α −/− mice. The sodium-restricting response to a low-sodium diet was unaffected in PKC-α −/− mice. Urinary osmolality was reduced to similar hypotonic levels in PKC-α −/− and +/+ mice during acute oral water loading or application of the vasopressin V2-receptor antagonist SR-121463. In comparison, the lower urinary osmolality observed in PKC-α −/− mice vs. wild-type mice under basal conditions persisted during water restriction for 36 h. In conclusion, PKC-α appears not to play a major role in renal sodium reabsorption but, consistent with its expression in the medullary collecting duct, contributes to urinary concentration in mice. Considering that PKC-βI and -βII are coexpressed with PKC-α in mouse medullary collecting duct, the present results indicate that conventional PKC isoenzymes cannot fully compensate for each other.
Synchronous Unit Activity and Local Field Potentials Evoked in the Subthalamic Nucleus by Cortical Stimulation
Authors: Magill Peter J. , Sharott Andrew , Bevan Mark D. , Brown Peter , Bolam J. Paul
Published: March 2004

The responses of single subthalamic nucleus (STN) neurons to cortical activation are complex and depend on the relative activation of several neuronal circuits, making theoretical extrapolation of single neuron responses to the population level difficult. To understand better the degree of synchrony imposed on STN neurons and associated neuronal networks by cortical activation, we recorded the responses of single units, pairs of neighboring neurons, and local field potentials (LFPs) in STN to discrete electrical stimulation of the cortex in anesthetized rats. Stimulation of ipsilateral frontal cortex, but not temporal cortex, generated synchronized “multiphasic” responses in neighboring units in rostral STN, usually consisting of a brief, short-latency excitation, a brief inhibition, a second excitation, and a long-duration inhibition. Evoked LFPs in STN consistently mirrored unit responses; brief, negative deflections in the LFP coincided with excitations and brief, positive deflections with inhibitions. This characteristic LFP was dissimilar to potentials evoked in cortex and structures surrounding STN and was resistant to fluctuations in forebrain activity. The short-latency excitation and associated LFP deflection exhibited the highest fidelity to low-intensity cortical stimuli. Unit response failures, which mostly occurred in caudal STN, were not associated with LFPs typical of rostral STN. These data suggest that local populations of STN neurons can be synchronized by both direct and indirect cortical inputs. Synchronized ensemble activity is dependent on topography and input intensity. Finally, the stereotypical, multiphasic profile of the evoked LFP indicates that it might be useful for locating the STN in clinical as well as nonclinical settings.