Enzyme replacement therapy stabilizes obstructive pulmonary Fabry disease associated with respiratory globotriaosylceramide storage

Fabry disease is an X-linked glycosphingolipidosis caused by a deficiency of α-galactosidase A, a lysosomal enzyme. Symptoms in hemizygous males and heterozygous females are due to lysosomal storage of globotriaosylceramide in the central and peripheral nervous system, vascular endothelium, cardiac valves and myocytes, gastrointestinal tract, and renal epithelium. Pulmonary involvement is also a recognized manifestation of Fabry disease, but histopathological evidence of pulmonary lysosomal storage is scant. We report a 51-year-old woman with a G43R α-galactosidase A mutation and normal spirometry testing 2.5 years prior to presentation, who experienced a dry, nonproductive cough that persisted despite treatment with antibiotics and bronchodilators. Spirometry demonstrated a mixed restrictive/obstructive pattern as well as impaired gas exchange. Patchy ground-glass pulmonary interstitial infiltrates were found on plain radiography and computerized tomography. She underwent an open lung biopsy that demonstrated peribronchiolar fibrosis and smooth-muscle hyperplasia. Prominent inclusion bodies of the bronchiolar/arteriolar smooth muscle and endothelium were present. Electron microscopy indicated the inclusion bodies were lamellated zebra bodies consistent with globotriaosylceramide storage. Enzyme replacement therapy (ERT) with agalsidase-beta was instituted. Since initiation of therapy, she occasionally has a dry cough but markers of obstructive lung disease have remained stable in the past 4 years. This report demonstrates that pulmonary involvement in Fabry disease is due to lysosomal storage, and suggests that ERT is capable of stabilizing pulmonary Fabry disease. However, progressive worsening of her total lung capacity indicates that ERT cannot reverse the ongoing process of fibrosis also seen in Fabry disease.

Environmental chemicals: from the environment to food, to breast milk, to the infant

Food is a source of exposure to many environmental chemicals found in human milk and other biological specimens. Ingestion of foods containing high amounts of animal fat is the main route of human exposure to lipophilic chemicals, such as persistent organic pollutants, which tend to bioaccumulate in the lipid compartment. Bioaccumulation results in increased exposure of these chemicals for humans, but particularly to breastfeeding infants, who are at the top of the food chain. The extent to which food contributes to a person's overall exposure depends on individual dietary habits and the concentrations of chemical residues in the food. These, in turn, are affected by (1) application methods, (2) properties and amounts of the chemical, and (3) preparation, handling, and the properties of the food. Once the food is ingested by the lactating woman, the chemical's pharmacokinetics and the transport mechanisms producing the movement of solutes across mammary alveolar cells determine the passage of chemicals from the blood to the milk. Thus, several factors affect the presence in human milk of environmental chemicals from dietary sources.

Neuromodulation of effects of upper limb motor function and shoulder range of motion by functional electric stimulation (FES)

Upper extremity motor impairment is a major contributing factor to functional disability of stroke patients. Functional electric stimulation (FES) is one of the therapeutic regimens for the management of upper extremity dysfunction after stroke. This review shows that therapeutic FES intervention on supraspinatus and posterior deltoid muscles for 6 weeks is effective to speed up upper limb motor recovery in hemiplegia of short-duration after stroke or less severely affected symptoms. The positive effect of FES could be attributable to neural mechanisms including: an enhanced information flow from the joint and muscle afferents, a better visual perception of the movement produced, and a stronger muscle contraction due to direct stimulation of the motor neuron. However, FES was demonstrated as not being effective in reducing the shoulder range of motion of external rotation in patients with either short- or long-duration hemiplegia. In order to offer better management in maintaining or improving limited shoulder range of motion, other types of electrical stimulation should be considered.

Aphis glycines as a Vector of Persistently and Nonpersistently Transmitted Viruses and Potential Risks for Soybean and Other Crops

The recently introduced soybean aphid (Aphis glycines), which is widespread in the soybean-growing regions in the United States, is the only aphid able to develop large colonies on soybean. Although its potential as a vector of plant viruses is recognized, reports on virus transmission efficiency by this aphid species are limited. In the present study, we examined the ability of A. glycines to transmit several economically important viruses. The results showed that A. glycines transmitted the potyviruses Bean yellow mosaic virus (BYMV) and Soybean mosaic virus from soybean to soybean more efficiently than Myzus persicae. However, M. persicae transmitted the alfamovirus Alfalfa mosaic virus and the potyviruses Tobacco etch virus (TEV) and Tobacco vein mottling virus (TVMV) from tobacco to tobacco more efficiently than A. glycines. This is the first report to demonstrate that the soybean aphid can vector TEV and TVMV, two economically important tobacco viruses. This also is the first report to document successful transmission of BYMV by A. glycines. All attempts to transmit the nepovirus Tobacco ringspot virus by A. glycines were unsuccessful, regardless of the length of the acquisition and inoculation feeding periods. Although the luteovirus Soybean dwarf virus (SbDV) was widely distributed in red and white clover in Kentucky, it was not detected in soybean. All transmission experiments of SbDV by A. glycines were unsuccessful. A reverse-transcription polymerase chain reaction (RT-PCR) assay was developed to detect SbDV in single aphids using a pair of primers designed to amplify a 372-bp PCR fragment in the coding region of SbDV coat protein. Although A. glycines was not a vector of SbDV, the virus was detected in 100% of tested aphids by RT-PCR after a 24- to 48-h virus acquisition access feeding. The practical applications of RT-PCR in detecting persistently transmitted viruses are discussed.

Development of a new rapid measurement technique for fish embryo membrane permeability studies using impedance spectroscopy

Information on fish embryo membrane permeability is vital in their cryopreservation. Whilst conventional volumetric measurement based assessment methods have been widely used in fish embryo membrane permeability studies, they are lengthy and reduce the capacity for multi-embryo measurement during an experimental run. A new rapid ‘real-time’ measurement technique is required to determine membrane permeability during cryoprotectant treatment. In this study, zebrafish (Danio rerio) embryo membrane permeability to cryoprotectants was investigated using impedance spectroscopy. An embryo holding cell, capable of holding up to 10 zebrafish embryos was built incorporating the original system electrods for measuring the impedance spectra. The holding cell was tested with deionised water and a series of KCl solutions with known conductance values to confirm the performance of the modified system. Untreated intact embryos were then tested to optimise the loading capacity and sensitivity of the system. To study the impedance changes of zebrafish embryos during cryoprotectant exposure, three, six or nine embryos at 50% epiboly stage were loaded into the holding cell in egg water, which was then removed and replaced by 0.5, 1.0, 2.0 or 3 M methanol or dimethyl sulfoxide (DMSO). The impedance changes of the loaded embryos in different cryoprotectant solutions were monitored over 30 min at 22 °C, immediately following embryo exposure to cryoprotectants, at the frequency range of 10–10⁶ Hz. The impedance changes of the embryos in egg water were used as controls. Results from this study showed that the optimum embryo loading level was six embryos per cell for each experimental run. The optimum frequency was identified at 10^3.14 or 1380 Hz which provided good sensitivity and reproducibility. Significant impedance changes were detected after embryos were exposed to different concentrations of cryoprotectants. The results agreed well with those obtained from conventional volumetric based studies.

Interaction of self-assembled monolayers of oligo(ethylene glycol)-terminated alkanethiols with water studied by vibrational sum-frequency generation

Vibrational sum-frequency generation (VSFG) was used to investigate the conformational changes in self-assembled monolayers (SAMs) of (1-mercaptoundec-11-yl) hexa(ethylene glycol) monomethylether (EG6-OMe) on gold when exposed to liquid water. VSFG spectra of the EG6-OMe SAMs were recorded before, during, and after exposure of the films to water and after a subsequent evacuation step. While in contact with water the entire ethylene glycol chains are found in a random, solvated state, after removal from the fluid water molecules remain absorbed only at the terminal groups of the film giving rise to distinct conformational changes. After evacuation, the structure of the EG6-OMe SAM reverts to its original state, indicating that water has been removed from the monolayer. Our findings support recent ab initio calculations and Monte Carlo simulations on the interaction of ethylene glycol-terminated monolayers with water.

Protein kinase C is involved in clozapine's facilitation of N-methyl-D-aspartate- and electrically evoked responses in pyramidal cells of the medial prefrontal cortex

We have previously shown that the atypical antipsychotic drug clozapine facilitates N-methyl-D-aspartate (NMDA)- and electrically evoked responses in pyramidal cells of the medial prefrontal cortex (mPFC). In the present study, we investigated the role of protein kinase C (PKC) in the action of clozapine. Bath administration of the PKC activator phorbol-12-myristate 13-acetate (PMA), but not the inactive isomer 4alpha-PMA, significantly enhanced the NMDA-evoked inward current and electrically evoked excitatory postsynaptic currents. Chelerythrine, a selective blocker of PKC, completely prevented the potentiating action produced by either clozapine or PMA on these currents in the mPFC cells. Intracellular injection of the PKC inhibitor PKC-I, but not the control substance PKC-S, through the recording electrode totally blocked clozapine's potentiating effect, indicating that a post-synaptic expressed PKC is critically involved in the augmenting action of clozapine on NMDA-evoked currents. Of the PKC inhibitor PKC-I, but not the control substance PKC-S, through the recording electrode totally blocked clozapine's potentiating effect, indicating that a post-synaptic expressed PKC is critically involved in the augmenting action of clozapine on NMDA-evoked currents. To further test the role of PKC in mediating the augmenting action of clozapine, we performed experiments in PKCgamma mutant and wild-type mice. In contrast to results in pyramidal cells from rats or wild-type mice, neither clozapine nor PMA was able to potentiate NMDA-induced currents in the mPFC from the PKCgamma mutant mice. Taken together, these results suggest that the PKC signal transduction pathway is critically involved in the facilitating action of clozapine on the NMDA-induced responses in pyramidal cells of the mPFC.

Olanzapine and clozapine but not haloperidol reverse subchronic phencyclidine-induced functional hyperactivity of N-methyl-D-aspartate receptors in pyramidal cells of the rat medial prefrontal cortex

In the present study, we have investigated and compared the ability of olanzapine, clozapine and haloperidol to modulate phencyclidine (PCP)-induced effect in pyramidal cells of the medial prefrontal cortex (mPFC) of rats using the techniques of intracellular recording and voltage-clamp. Subchronic treatment of rats with PCP (2 mg/kg, b.i.d., 7 days, 48-60 h withdrawal) produced: (1) a depolarized resting membrane potential, a decrease of slow after hyperpolarization (sAHP) and spike frequency adaptation, (2) a shift of the concentration response curve of N-methyl-D-aspartate (NMDA), but not (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA), to the left, (3) a decrease of the paired pulse facilitation (PPF) with an increase of excitatory postsynaptic current variance (EPSC variance), and (4) a reduction of the blockade of NMDA response by in vitro application of PCP. Repeated treatment with either olanzapine or clozapine, but not haloperidol, completely prevented the aforementioned subchronic PCP-induced effects. The present results indicate that the atypical antipsychotic drugs (APDs) clozapine and olanzapine share a common property in preventing subchronic PCP-induced functional hyperactivity of NMDA receptors.

Effect of Aphid Behavior on Efficiency of Transmission of Soybean mosaic virus by the Soybean-Colonizing Aphid, Aphis glycines

The soybean aphid (Aphis glycines) was a poor vector (0.83% transmission) when the aphids were allowed overnight acquisition feed on Soybean mosaic virus (SMV)-infected soybean leaves. However, A. glycines was shown to be a very efficient vector (34.72% transmission) when individual aphids were allowed a 1-min acquisition probe on the same infected leaves used for the feeding treatment. Similar results were obtained with Myzus persicae and tobacco in transmission experiments of the potyviruses Tobacco etch virus (feeding: 1.36%; probing: 45.5%) and Tobacco vein mottling virus (feeding: 2.0%; probing: 47.5%). A reverse transcription-polymerase chain reaction (RT-PCR) assay was developed to detect SMV in single soybean aphids using a pair of primers designed to amplify a 469-bp PCR fragment in the coding region of SMV coat protein. In contrast to the low transmission rate obtained with the soybean aphids that acquired virus through overnight feeding, RT-PCR detected SMV in 100% of these aphids. Interestingly, the rate of SMV detection by RT-PCR in aphids that were allowed a 1-min acquisition probe (31.67%) coincided with percent transmission (34.72%). The practical application of RT-PCR in detecting nonpersistently transmitted viruses and its implications for virus epidemiology are discussed.

Combined carotid arteries-aortic arch transplantation in rats: development of a new microsurgical model

A new microsurgical model of combined carotid arteries-aortic arch transplantation in the rat is described. In this model, the combined carotid arteries-aortic arch were harvested and end-to-end anastomosed to the recipient's right carotid artery using a sleeve anastomosis technique. The total graft ischemia time and in particular the time required to perform the arterial anastomoses was significantly reduced. No surgical failure was encountered. Ten-day graft patency was 100% (15/15). Our study results demonstrated that the sleeve anastomosis technique for combined carotid arteries-aortic arch transplantation in the rat is fast and easy to perform and has a high rate of success.

Functional ability, perceived exertion and employment of the individuals with spinal cord lesion in Taiwan

STUDY DESIGN

A survey on functional ability, perceived exertion, and employment was mailed to 190 individuals with spinal cord lesion. Analysis is based on the 91 completed replies.

OBJECTIVES

To establish a database of individuals with spinal cord lesions and to assess the effectiveness of training programs designed to improve life quality and employment chances among the individuals with spinal cord lesion.

SETTINGS

Subjects selected from the Spinal Cord Injury Association of the Republic of China (SCIAROC) and from the Asylum Center Spinal Cord Injury (ASCCI) in Taiwan.

METHODS

Information was obtained from a survey sent to the subjects who are chosen randomly from the SCIAROC and from all the subjects through ACSCI training program.

RESULTS

Respondents in ACSCI had a higher functional activity level and lower perceived exertion during activities than those in SCIAROC. The employment status is related to the functional independence and level of injury.

CONCLUSION

The database provides information on functional and employment status of individuals with spinal cord lesion. The present study also demonstrates the efficacy of a vocational training program for individuals with spinal cord lesion in Taiwan.

Protective effects of treadmill training on infarction in rats

This study was undertaken to determine the protective effects of treadmill training on brain ischemic lesions caused by middle cerebral artery (MCA) occlusion in male rats. Rats were divided into four groups: control, 1-week treadmill pre-training, 2-week treadmill pre-training, and 4-week treadmill pre-training. Cerebral infarction was induced by MCA occlusion for 60 min, followed by reperfusion. After 24 h, rats were killed and brain slices were then stained to assess lesion size. Treadmill training at least for 2 weeks can reduce the infarction size and edema caused by MCA occlusion (P<0.01). The present study provides evidence that treadmill training reduces ischemic brain damage in an animal model of cerebral ischemia.

Effect of genotoxic exposure to chromium among electroplating workers in Taiwan

The objective of this study was to investigate the association between chromium (Cr) concentrations and sister chromatid exchanges (SCE) formation in Cr workers and to assess the effects of susceptible genes (glutathione S-transferase M1 and T1) on the frequency of deletion and SCE/cell. Urinary Cr concentration was significantly elevated in Cr workers (3.67 +/- 3.89 microg/g creatinine) compared to control group (1.21 +/- 1.16 microg/g creatinine, P < 0.01). There was also a significant difference of superoxide dismutase (SOD) levels between Cr workers (6.86 +/- 0.80 U/mg Hb) and controls (7.16 +/- 0.53 U/mg Hb, P < 0.01). The frequencies of SCE and high frequency cells (HFC) were significantly correlated with smoking habits and with duration of exposure to Cr. A significantly higher percentage (50%) of Cr workers had both the null GSTM1 and GSTT1 genotype as compared to 10% of the controls (P < 0.01). However, the chromosomal DNA damage effect of GSTM1 and GSTT1 genotypes, individually or in combination, was not revealed in Cr exposed workers.

Biphasic modulation of NMDA-induced responses in pyramidal cells of the medial prefrontal cortex by Y-931, a potential atypical antipsychotic drug

Similar to the effects produced by the atypical antipsychotic drugs (APDs) clozapine and olanzapine, Y-931 [8-fluoro-12-(4-methylpiperazin-1-yl)-6H-[1]benzothieno[2,3-b][1,5]benzodiazepine maleate, a purported atypical APD] effectively facilitated N-methyl-D-aspartate (NMDA)-induced, but not (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)-evoked, responses in pyramidal cells of the rat medial prefrontal cortex (mPFC). Similar to olanzapine and clozapine, the concentration-response curve of Y-931 in these experiments was biphasic. At present, the mechanisms behind the biphasic modulatory actions of Y-931 and olanzapine on NMDA-induced currents in the mPFC are not clear. In addition to augmenting NMDA responses, Y-931 prevented the phencyclidine (PCP)-induced block of the NMDA responses and increased the amplitudes and durations of excitatory postsynaptic currents (EPSCs) evoked by electrical stimulation of the forceps minor. Overall, our findings suggest that APDs, particularly the atypical ones, share a common property in that they facilitate NMDA receptor-mediated transmission in the mPFC and perhaps other functionally related limbic structures as well, which could be the cellular basis for their ability to alleviate some schizophrenic negative symptoms and cognitive dysfunctions.

The presence of a newly identified infectious agent (SEN virus) in patients with liver diseases and in blood donors in Japan

The existence of the newly discovered SEN virus (SENV) was investigated in 379 Japanese patients with liver diseases and in 277 blood donors, to determine whether SENV is associated with non-A-E hepatitis. SENV DNA was detected by seminested polymerase chain reaction, with primers directed to 2 SENV strains: SENV-H and SENV-D. SENV was detected in 7 (32%) of 22 patients with fulminant hepatitis, in 15 (17%) of 86 patients with acute hepatitis, in 38 (27%) of 139 patients with chronic hepatitis, in 29 (31%) of 93 patients with liver cirrhosis, in 5 (33%) of 15 patients with autoimmune hepatitis, in 11 (46%) of 24 patients with primary biliary cirrhosis, and in 27 blood donors (10%). Infection occurred more frequently in patients with liver diseases than in blood donors; however, there were no significant differences in SENV-positive rates between patients with non-A-C hepatitis and those with acute or chronic hepatitis due to known hepatitis virus or nonviral liver disease. This study did not suggest SENV as a possible causative agent of non-A-C hepatitis.

A leukemic stem cell with intrinsic drug efflux capacity in acute myeloid leukemia

The hematopoietic stem cell underlying acute myeloid leukemia (AML) is controversial. Flow cytometry and the DNA-binding dye Hoechst 33342 were previously used to identify a distinct subset of murine hematopoietic stem cells, termed the side population (SP), which rapidly expels Hoechst dye and can reconstitute the bone marrow of lethally irradiated mice. Here, the prevalence and pathogenic role of SP cells in human AML were investigated. Such cells were found in the bone marrow of more than 80% of 61 patients and had a predominant CD34(low/-) immunophenotype. Importantly, they carried cytogenetic markers of AML in all 11 cases of active disease examined and in 2 out of 5 cases in complete hematological remission. Comparison of daunorubicin and mitoxantrone fluorescence emission profiles revealed significantly higher drug efflux from leukemic SP cells than from non-SP cells. Three of 28 SP cell transplants generated overt AML-like disease in nonobese diabetic--severe combined immunodeficient mice. Low but persistent numbers of leukemic SP cells were detected by molecular and immunological assays in half of the remaining mice. Taken together, these findings indicate that SP cells are frequently involved in human AML and may be a target for leukemic transformation. They also suggest a mechanism by which SP cells could escape the effects of cytostatic drugs and might eventually contribute to leukemia relapse. (Blood. 2001;98:1166-1173)

Syndromic ear anomalies and renal ultrasounds

OBJECTIVE

Although many pediatricians pursue renal ultrasonography when patients are noted to have external ear malformations, there is much confusion over which specific ear malformations do and do not require imaging. The objective of this study was to delineate characteristics of a child with external ear malformations that suggest a greater risk of renal anomalies. We highlight several multiple congenital anomaly (MCA) syndromes that should be considered in a patient who has both ear and renal anomalies.

METHODS

Charts of patients who had ear anomalies and were seen for clinical genetics evaluations between 1981 and 2000 at Cedars-Sinai Medical Center in Los Angeles and Dartmouth-Hitchcock Medical Center in New Hampshire were reviewed retrospectively. Only patients who underwent renal ultrasound were included in the chart review. The literature was reviewed for the epidemiology of renal anomalies in the general population and in MCA syndromes with external ear anomalies. We defined a child as having an external ear anomaly when he or she had any of the following: preauricular pits and tags; microtia; anotia; or cup, lop, and other forms of dysplastic ears. A child was defined as having a renal anomaly if an ultrasound revealed any of the following: unilateral or bilateral renal agenesis; hypoplasia; crossed ectopia; horseshoe, pelvic, cystic kidney; hydronephrosis; duplicated ureters; megaureter; or vesicoureteric reflux.

RESULTS

Because clinical genetics assessments were made by the same clinician at both sites (J.M.G.), data were combined. A total of 42 patients with ear anomalies received renal ultrasound; 12 (29%) of them displayed renal anomalies. Of the 12 patients with renal anomalies, 11 (92%) also received a diagnosis of MCA syndrome. Eleven of 33 patients (33%) with MCA syndromes had renal anomalies, whereas 1 of 9 patients (11%) with isolated ear anomalies had renal anomalies. Specific disorders seen were CHARGE association, Townes-Brocks syndrome, branchio-oto-renal syndrome, Nager syndrome, and diabetic embryopathy.

CONCLUSIONS

We conclude that ear malformations are associated with an increased frequency of clinically significant structural renal anomalies compared with the general population. This is due to the observation that auricular malformations often are associated with specific MCA syndromes that have high incidences of renal anomalies. These include CHARGE association, Townes-Brocks syndrome, branchio-oto-renal syndrome, Nager syndrome, Miller syndrome, and diabetic embryopathy. Patients with auricular anomalies should be assessed carefully for accompanying dysmorphic features, including facial asymmetry; colobomas of the lid, iris, and retina; choanal atresia; jaw hypoplasia; branchial cysts or sinuses; cardiac murmurs; distal limb anomalies; and imperforate or anteriorly placed anus. If any of these features are present, then a renal ultrasound is useful not only in discovering renal anomalies but also in the diagnosis and management of MCA syndromes themselves. A renal ultrasound should be performed in patients with isolated preauricular pits, cup ears, or any other ear anomaly accompanied by 1 or more of the following: other malformations or dysmorphic features, a family history of deafness, auricular and/or renal malformations, or a maternal history of gestational diabetes. In the absence of these findings, renal ultrasonography is not indicated.

Stimulatory effect of lactate on testosterone production by rat Leydig cells

Previously we found that the increased plasma testosterone levels in male rats during exercise partially resulted from a direct and luteinizing hormone (LH)-independent stimulatory effect of lactate on the secretion of testosterone. In the present study, the acute and direct effects of lactate on testosterone production by rat Leydig cells were investigated. Leydig cells from rats were purified by Percoll density gradient centrifugation subsequent to enzymatic isolation of testicular interstitial cells. Purified rat Leydig cells (1 x 10(5) cells/ml) were in vitro incubated with human chorionic gonadotropin (hCG, 0.05 IU/ml), forskolin (an adenylyl cyclase activator, 10(-5) M), or 8-bromo-adenosine-3':5'-cyclic monophosphate (8-Br-cAMP, 10(-4) M), SQ22536 (an adenylyl cyclase inhibitor, 10(-6)-10(-5) M), steroidogenic precursors (25-hydroxy-cholesterol, pregnenolone, progesterone, and androstenedione, 10(-5) M each), nifedipine (a L-type Ca(2+) channel blocker, 10(-5)-10(-4) M), or nimodipine (a potent L-type Ca(2+) channel antagonist, 10(-5)-10(-4) M) in the presence or absence of lactate at 34 degrees C for 1 h. The concentration of medium testosterone was measured by radioimmunoassay. Administration of lactate at 5-20 mM dose-dependently increased the basal testosterone production by 63-187% but did not alter forskolin- and 8-Br-cAMP-stimulated testosterone release in rat Leydig cells. Lactate at 10 mM enhanced the stimulation of testosterone production induced by 25-hydroxy-cholesterol in rat Leydig cells but not other steroidogenic precursors. Lactate (10 mM) affected neither 30- nor 60-min expressions of cytochrome P450 side chain cleavage enzyme (P450scc) and steroidogenic acute regulatory (StAR) protein. The lactate-stimulated testosterone production was decreased by administration of nifedipine or nimodipine. These results suggested that the physiological level of lactate stimulated testosterone production in rat Leydig cells through a mechanism involving the increased activities of adenylyl cyclase, cytochrome P450scc, and L-type Ca(2+) channel.

Efficacy of candesartan cilexetil as add-on therapy in hypertensive patients uncontrolled on background therapy: a clinical experience trial. ACTION Study Investigators

A large-scale, 8-week, open-label, clinical experience trial evaluated the efficacy of the angiotensin II receptor (AT1 subtype) blocker candesartan cilexetil (16 to 32 mg once daily) either alone or as add-on therapy in 6465 hypertensive patients. The study population was 52% female and 16% African American with a mean age of 58 years. It included 5,446 patients who had essential hypertension (HBP) and 1,014 patients who had isolated systolic hypertension (ISH). These patients had either untreated or uncontrolled hypertension (systolic blood pressure [SBP] 140 to 179 mm Hg or diastolic blood pressure [DBP] 90 to 109 mm Hg inclusive at baseline) despite a variety of antihypertensive medications including diuretics, calcium antagonists, angiotensin converting enzyme (ACE) inhibitors, and alpha- or beta-blockers, either singly or in combination. The mean baseline blood pressure for the HBP group was 156/97 mm Hg. Candesartan cilexetil as monotherapy (in 51% of HBP patients) reduced mean SBP/DBP by 18.7/ 13.1 mm Hg. As add-on therapy (in 49% of HBP patients) to various background therapies, candesartan cilexetil consistently reduced mean SBP/DBP further, irrespective of the background therapy: diuretics (17.8/11.3 mm Hg), calcium antagonists (16.6/11.2 mm Hg), beta-blockers (16.5/ 10.4 mm Hg), ACE inhibitors (15.3/10.0 mm Hg), alpha-blockers (16.4/10.4 mm Hg). The mean baseline blood pressure for the ISH group was 158/81 mm Hg. Candesartan cilexetil, as monotherapy (in 34% of ISH patients), reduced SBP/DBP by 17.0/4.4 mm Hg. As add-on therapy (in 66% of ISH patients) to various background therapies, candesartan cilexetil consistently reduced mean SBP/DBP further, irrespective of the background therapy: diuretics (17.4/5.1 mm Hg), calcium antagonists (15.6/3.6 mm Hg), beta-blockers (14.0/4.8 mm Hg), ACE inhibitors (13.4/4.3 mm Hg), and alpha-blockers (11.6/4.5 mm Hg). The further blood pressure lowering effects of candesartan cilexetil as add-on therapy were seen regardless of age, sex, and race. Overall, 6.8% of the 6465 patients withdrew because of adverse events, most commonly headache (6.3%) and dizziness (5.0%). Orthostatic hypotension was infrequent; 0.2% with candesartan cilexetil alone, and 0.8% with candesartan cilexetil as add-on therapy. Thus, candesartan cilexetil either alone or as add-on therapy was highly effective for the control of systolic or diastolic hypertension regardless of demographic background when used in typical clinical practice settings.

SEN virus infection and its relationship to transfusion-associated hepatitis

SEN virus (SEN-V) is a recently identified single-stranded, circular DNA virus. Two SEN-V variants (SENV-D and SENV-H) were assayed by polymerase chain reaction (PCR) to investigate their role in the causation of transfusion-associated non-A to E hepatitis. The incidence of SEN-V infection after transfusion was 30% (86 of 286) compared with 3% (3 of 97) among nontransfused controls (P < .001). Transfusion risk increased with the number of units transfused (P < .0001) and donor-recipient linkage for SEN-V was shown by sequence homology. The prevalence of SEN-V in 436 volunteer donors was 1.8%. Among patients with transfusion-associated non-A to E hepatitis, 11 of 12 (92%) were infected with SEN-V at the time of transfusion compared with 55 of 225 (24%) identically followed recipients who did not develop hepatitis (P < .001). No effect of SEN-V on the severity or persistence of coexistent hepatitis C virus (HCV) infection was observed. In 31 infected recipients, SEN-V persisted for greater than 1 year in 45% and for up to 12 years in 13%. SEN-V-specific RNA (a possible replicative intermediate) was recovered from liver tissue. In summary, SENV-D and -H were present in nearly 2% of US donors, and were unequivocally transmitted by transfusion and frequently persisted. The strong association of SEN-V with transfusion-associated non-A to E hepatitis compared with controls raises the possibility, but does not establish that SEN-V might be a causative agent of posttransfusion hepatitis. The vast majority of SEN-V-infected recipients did not develop hepatitis.

The effects of sodium bicarbonate on thioridazine-induced cardiac dysfunction in the isolated perfused rat heart

To determine the site of thioridazine-induced cardiotoxicity and investigate the effectiveness of sodium bicarbonate (NaHCO3) therapy, isolated rat hearts were perfused with Krebs-Henseleit-Bicarbonate buffer (KHB) at a constant coronary flow of 10 mL/min and electrically paced at 300 bpm. Experimental protocol included 15 min intervals of KHB, thioridazine (TDZ), TDZ + NaHCO3, KHB. Left ventricular (LV) pressure was measured with a balloon-tipped catheter placed in the LV via the mitral valve. Coronary perfusion pressure was monitored continuously as an index of coronary vascular resistance (CVR). LV generated pressure (LVGP) was used as our index of cardiac function and was calculated by subtracting LV end diastolic pressure (LVEDP) from LV peak systolic pressure (LVPSP). TDZ at 7,500 ng/mL was chosen as the toxic dose. NaHCO3 treatment was at an approximate sodium = 155 mM and pH = 7.60. Hearts perfused with TDZ resulted in a progressive decrease in LVGP. After 15 min of TDZ perfusion, LVGP decreased by 50%, and 75% at 30 min (n = 5). TDZ increased LVEDP and decreased LVPSP. TDZ perfusion increased CVR by 83%. In another experiment, hearts were perfused with TDZ for 15 min and then for an additional 15 min with TDZ + NaHCO3. NaHCO3 treatment transiently (approximately 5 min) increased LVGP by 23% (n=5). During NaHCO3 treatment, LVPSP increased and LVEDP and CVR decreased during the first 5 min. During the remainder of the NaHCO3 protocol, the hearts failed, similar to TDZ alone. TDZ diminished left ventricular function and promoted coronary artery vasoconstriction. NaHCO3 temporariy reversed these toxic effects.

The simulation effects of mountain climbing training on selected endocrine responses

The simulation effects of mountain climbing exercise training on plasma testosterone, cortisol and luteinizing hormone (LH) levels were examined in ten recreational mountain male climbers. Subjects underwent a simulating mountain climbing exercise training 3 times a week for a total of eight weeks before an expedition to Mount Muztag Ata (7546 m, Xingian, China). During training, each subject carried a 40 kg back pack while walking on a treadmill at a speed of 1.9 mph for 60 min at sea level. Subjects completed an incremental treadmill test to exhaustion prior to training, after training, and one week after returning from Mount Muztag Ata. Blood samples were collected from antecubital vein at rest and at 5, 60, and 120 min post testing to determine the plasma testosterone, cortisol and LH levels. The basal plasma testosterone and cortisol concentrations were lower in both post-training and after-climbing conditions compared with that in the pre-training condition (p<0.01). The basal plasma LH concentration was remained unchanged after training and after the mountain climbing compared with levels measured in the pre-training phase. No correlation could be established between plasma LH and testosterone level. These results suggest that an eight-week period of mountain climbing training protocol may be beneficial in maintaining normal endocrine function during and after high altitude mountain expedition. Our results also indicate the decrease of plasma testosterone was LH independent.

Subchronic treatment with either clozapine, olanzapine or haloperidol produces a hyposensitive response of the rat cortical cells to N-methyl-D-aspartate

Using the technique of intracellular recording in in vitro brain slice preparations, we examined the effects produced by repeated administration of the antipsychotic drugs clozapine, olanzapine and haloperidol, on N-methyl-D-aspartic acid-induced responses in pyramidal cells of the rat medial prefrontal cortex. Rats were anesthetized and decapitated 24h after the conclusion of daily intraperitoneal injection with either clozapine (25mg/kg), olanzapine (1, 5 or 10mg/kg) or haloperidol (0.5mg/kg) for 21 days, and the slices from medial prefrontal cortex were used for electrophysiological recordings. The concentration-response curves for N-methyl-D-aspartic acid to activate cortical cells shifted markedly to the right in rats which received the subchronic antipsychotic drug treatment, compared with those obtained from rats which received repeated injections of vehicle (1ml/kg/day, i.p. for 21 days). In addition, repeated exposure to antipsychotic drugs caused a significant reduction in the ability of these antipsychotic drugs to augment the N-methyl-D-aspartic acid-induced inward current in pyramidal cells of the rat medial prefrontal cortex. Repeated administration of haloperidol, but not clozapine or olanzapine, significantly hyperpolarized the resting membrane potential and increased membrane resistance in pyramidal cells of the medial prefrontal cortex. Moreover, subchronic treatment with haloperidol, but not clozapine or olanzapine, depressed (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid-induced responses. The desensitized response of medial prefrontal cortex cells to N-methyl-D-aspartic acid could be the result of a compensatory response to the facilitating action of antipsychotic drugs on N-methyl-D-aspartic acid receptor-mediated transmission. The inhibitory action of haloperidol on (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid responses may also contribute to the rightward shift of the N-methyl-D-aspartic acid concentration-response curve.Thus, the present study suggests that the atypical antipsychotic drugs, clozapine and olanzapine, as well as the typical antipsychotic drug haloperidol strongly modulate glutamatergic transmission after prolonged treatment. This might be an important factor in the mechanisms by which these drugs alleviate symptoms in schizophrenic patients.

Genomic and molecular evolutionary analysis of a newly identified infectious agent (SEN virus) and its relationship to the TT virus family

A new group of transmissible single-stranded (ss) DNA viruses (SENV) distantly related to the large TT virus (TTV) family was recently identified. Eight different SENV isolates have been found, some with an association with posttransfusion hepatitis. A phylogenetic analysis of near-complete open-reading frame 1, including conserved motifs and excluding recombinant regions, was performed. The analysis used TTV-like minivirus as an outgroup, to determine a root of the phylogenetic tree, and compared 8 SENV isolates, 6 prototype TTV isolates, and 7 TTV variants (including SANBAN, TUS01, PMV, and YONBAN). Four distinct clusters separated by a bootstrap value of 100% were observed. YONBAN isolates formed a distinct outer group, representing the earliest recognized phylogenetic divergence (group 1). Prototype TTV formed group 2, PMV formed group 3, and SENV, SANBAN, and TUS01 isolates formed group 4, the most recently evolved group. This taxonomic classification suggests that these circular ssDNA viruses probably evolved from a common ancestor virus.

Comparative efficacy as antioxidants between ascorbic acid and epigallocatechin gallate on cells of two human lymphoblastoid lines

Both ascorbic acid and epigallocatechin gallate, which is one of the key polyphenols contained in green tea leaves, have been considered excellent antioxidants. The present study compared the efficacy as antioxidants between the two agents on an equimolar basis. Cells of two lymphoid lines were used as test material to determine the reduction of chromosome damage induced by the radiomimetic antibiotic bleomycin. Without bleomycin, both agents, at concentrations of 10(-7), 10(-6), 10(-5), and 10(-4) M, showed chromosome damage similar to the untreated controls. With bleomycin, the weakest concentration of both showed no protective effect. At concentrations of 10(-6) and 10(-5) M, especially the latter, a significant reduction in frequencies of chromatid breaks was recorded. However, at the highest concentration, 10(-4) M, the chromatid break frequencies rose to the same level as that of cells treated with bleomycin alone, suggesting that both behaved like pro-oxidants.