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Background/purpose: Intracranial dural arteriovenous fistulas (DAVFs) can be complicated by ischemic stroke. This study investigated the frequency and determinants of ischemic stroke in patients with intracranial DAVF., Methods: We conducted a retrospective study of consecutive patients with intracranial DAVF. Patients with pure hemorrhagic stroke or without available brain imaging for clarifying stroke type were excluded. DAVF was diagnosed by cerebral catheter angiography. Cognard classification and location of DAVFs were ascertained. The clinical characteristics, outcome, and radiographic findings were recorded. Factors associated with occurrence of ischemic stroke in the patients with DAVFs were determined., Results: A total of 134 patients were enrolled. Six patients (4.5%) had ischemic stroke (mean age: 53.8 ± 13.4 years) and 128 patients were free from stroke (mean age: 55.4 ± 15.2 years). Men accounted for 83% in the ischemic stroke group and 34% in the non-stroke group. Chemosis, exophthalmos and tinnitus were more frequent in the non-stroke group, whereas seizure and mental decline were more frequent in the ischemic stroke group. DAVF was associated with highest risk of ischemic stroke at locations other than the cavernous sinus or large sinuses. Ischemic stroke also correlated with types of DAVF involving cortical venous drainage, including type IIb (18%), III (15%), and IV (100%). No patient with DAVF type I and IIa had ischemic stroke. The rate of ischemic stroke in patients with concomitant DAVF and cerebral sinus thrombosis was higher than in DAVF patients without cerebral sinus thrombosis. Venous infarct was the major subtype of ischemic stroke in five DAVF patients. Endovascular therapy was the most common choice in both groups, and fewer patients in the ischemic stroke group did not receive any treatment for DAVFs., Conclusion: Location and type of DAVF were two important factors related to the occurrence of ischemic stroke in DAVF patients., (Copyright © 2011 Formosan Medical Association & Elsevier. Published by Elsevier B.V. All rights reserved.)

Precursor B cell acute lymphoblastic leukemia (pre-B ALL) affects five to six thousand adults and almost three thousand children every year. Approximately 25% of the children and 60% of the adults die from their disease, highlighting the need for new therapies that complement rather than overlap chemotherapy and bone marrow transplantation. Immunotherapy is a class of therapies where toxicities and mechanisms of action do not overlap with those of chemotherapy. Because CD19 is a B cell- restricted membrane antigen that is expressed on the majority of pre-B tumor cells, a CD19-based immunotherapy is being developed for ALL. In this study, the anti-tumor activities of immunotoxins (ITs) constructed by conjugating a murine monoclonal antibody (MAb), HD37, or its chimeric (c) construct to recombinant ricin toxin A chain (rRTA) were compared both in vitro using human pre-B ALL and Burkitt's lymphoma cell lines and in vivo using a disseminated human pre-B ALL tumor cell xenograft model. The murine and chimeric HD37 IT constructs were equally cytotoxic to pre-B ALL and Burkitt's lymphoma cells in vitro and their use in vivo resulted in equivalent increases in survival of SCID mice with human pre-B ALL tumors when compared with control mice.

Valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, is known to protect against cerebral ischemia. The effects of VPA on blood-brain barrier (BBB) disruption were investigated in rats subjected to transient middle cerebral artery occlusion (MCAO). Postischemic VPA treatment remarkably attenuated MCAO-induced BBB disruption and brain edema. Meanwhile, VPA significantly reduced MCAO-induced elevation of matrix metalloproteinase-9 (MMP-9), degradation of tight junction proteins, and nuclear translocation of nuclear factor-κB (NF-κB). Sodium butyrate, another HDAC inhibitor, mimicked these effects of VPA. Our findings suggest that BBB protection by VPA involves HDAC inhibition-mediated suppression of NF-κB activation, MMP-9 induction, and tight junction degradation.

Mesenchymal stem cells (MSCs) show high potential for the therapy of several human diseases; however, the effectiveness of MSC transplantation has been hampered by the relatively poor migratory capacity of these cells toward disease target sites. This study investigated whether treatment of MSCs with two mood stabilizers-valproic acid (VPA) and lithium-would enhance cell migration and, if so, to explore the mechanisms underlying their effects. Short-term (3 h) exposure of MSCs to a relatively high concentration (2.5 mM) of VPA markedly increased the transcript and protein levels of CXC chemokine receptor 4 (CXCR4). VPA-induced CXCR4 expression required inhibition of histone deacetylases (HDACs), including the HDAC1 isoform, and involved histone hyperacetylation at the promoter region of the CXCR4 gene. Notably, VPA treatment enhanced stromal cell-derived factor-1α (SDF-1α)-mediated MSC migration, which was completely blocked by AMD3100, a CXCR4 antagonist. Treatment of MSCs with lithium (2.5 mM for 1 day) selectively elevated the transcript and protein levels of matrix metalloproteinase-9 (MMP-9) and its enzymatic activity; these effects were mimicked by inhibition or gene silencing of glycogen synthase kinase-3β (GSK-3β). Lithium treatment also potentiated SDF-1α-dependent MSC migration across the extracellular matrix, which was suppressed by two MMP-9 inhibitors, doxycycline and GM6001. Combining VPA and lithium treatment further increased MSC migration. Overall, VPA and lithium stimulated MSC migration through distinct targets and mediators: HDAC-CXCR4 and GSK-3β-MMP-9, respectively.

Background and Purpose: Pulsatile tinnitus is a common symptom of intracranial dural arteriovenous fistulas (DAVF). This study aims to characterize the clinical and ultrasonographic features of DAVF in patients with pulsatile tinnitus., Methods: We compared the characteristics of DAVF and carotid duplex sonography (CDS) results between 67 DAVF patients with and without pulsatile tinnitus. We also investigated the relationship between changes in tinnitus status and serial CDS changes in 25 DAVF patients with pulsatile tinnitus., Results: Pulsatile tinnitus was highly associated with the location and feeding arteries of DAVF (P < .001). The sensitivity of resistive index (RI; Norm, >.72) and end diastolic velocity (EDV; Norm, <21 cm/sec) of external carotid artery (ECA) in CDS study for diagnosing DAVF in patients with pulsatile tinnitus was 95% and 92%, respectively. Changes of RI and EDV of ECA also correlated with the changes of tinnitus status., Conclusions: RI and EDV of ECA have high diagnostic sensitivity and reliability for detecting DAVF in patients with pulsatile tinnitus., (Copyright © 2009 by the American Society of Neuroimaging.)

Cobicistat (3, GS-9350) is a newly discovered, potent, and selective inhibitor of human cytochrome P450 3A (CYP3A) enzymes. In contrast to ritonavir, 3 is devoid of anti-HIV activity and is thus more suitable for use in boosting anti-HIV drugs without risking selection of potential drug-resistant HIV variants. Compound 3 shows reduced liability for drug interactions and may have potential improvements in tolerability over ritonavir. In addition, 3 has high aqueous solubility and can be readily coformulated with other agents.

Objectives: Early diagnosis and management of intracranial dural arteriovenous fistulae (DAVF) may prevent the occurrence of stroke. This study aimed to identify the best carotid duplex sonography (CDS) parameters for screening DAVF., Methods: 63 DAVF patients and 170 non-DAVF patients received both CDS and conventional angiography. The use of seven CDS haemodynamic parameter sets related to the resistance index (RI) of the external carotid artery (ECA) for the diagnosis of DAVF was validated and the applicability of the best CDS parameter set in 20 400 patients was tested., Results: The CDS parameter set (ECA RI (cut-off point = 0.7) and internal carotid artery (ICA) to ECA RI ratio (cut-off point = 0.9)) had the highest specificity (99%) for diagnosis of DAVF with moderate sensitivity (51%). Location of the DAVF was a significant determinant of sensitivity of detection, which was 70% for non-cavernous DAVF and 0% for cavernous sinus DAVF (p<0.001). The above parameter set detected abnormality in 92 of 20 400 patients. These abnormalities included DAVF (n = 25), carotid stenosis (n = 32), vertebral artery stenosis (n = 7), intracranial arterial stenosis (n = 6), head and neck tumour (n = 3) and unknown aetiology (n = 19)., Conclusion: Combined CDS parameters of ECA RI and ICA to ECA RI ratio can be used as a screening tool for the diagnosis of DAVF.

Stroke centers and intravenous tissue plasminogen activators (tPA) are effective management for acute ischemic stroke. This study aimed to analyze stroke center characteristics on the administration of thrombolytic therapy. A national survey of stroke centers in academic medical centers and regional teaching hospitals in Taiwan was conducted. The survey questions included the number of tPA or other thrombolytic therapies, presence of stroke intensive care units and wards, initiation of rehabilitation, and 15 criteria for establishment of stroke centers adopted from the Brain Attack Coalition's recommendation. Factors influencing administration of thrombolytic therapy were analyzed. Intravenous tPA increased from 135 cases in 2004 to 246 cases in 2006, accounting for approximately 0.4% and 0.8% of all acute ischemic stroke patients in Taiwan, respectively. The frequency of thrombolytic therapy administration significantly correlated with stroke center criteria (Spearman's rho=0.731, P<0.001). Multivariate analysis showed routine intravenous tPA protocol in the emergency room (odds ratio=4.6, P=0.042) and supervision by the stroke center director (odds ratio=3.7, P=0.031) significantly influenced the administration of thrombolytic therapy. Well-organized stroke centers, routine use of thrombolytic therapy protocols in the emergency room, and guidance by a stroke center director are important for enhancing thrombolytic therapy in patients with acute ischemic stroke.

Survival motor neuron (SMN) messenger RNA and protein levels in spinal muscular atrophy (SMA) model mice and in patients with SMA were measured. There was a high correlation between leukocyte and spinal cord SMN expression in SMA model mice and a moderate correlation between leukocyte SMN expression and age of disease onset in patients with SMA.

Background and Purpose: It is still controversial whether the nature of cerebral infarcts differs between cancer patients and the general population. The aim of this study is to delineate the characteristics of acute cerebral infarction in patients with active malignancy using diffusion-weighted imaging (DWI)., Materials and Methods: Seventy consecutive patients with both active malignancy and acute cerebral infarction (confirmed by DWI) were retrospectively included. These 70 were divided into 3 groups on the basis of infarct pattern: embolic infarction, large artery disease, and lacunar infarction. Medical records were reviewed in detail for demographic data, cancer information, vascular risk factors, and prognosis., Results: Two thirds of cancer patients had multiple infarcts, and 30% of infarcts were located infratentorially. Embolic infarction, large artery disease, and lacunar infarction occurred in 60, 31, and 9% of cancer patients, respectively. Gastrointestinal (GI) cancer was significantly related to embolic infarction (odds ratio 4.64, p = 0.04). The 3-month mortality rates were higher in patients with rather than without cancer metastasis (68 vs. 8%; p < 0.001)., Conclusions: Cerebral infarcts in cancer patients tended to be embolic and multiple. Patients with GI cancer were particularly susceptible to embolic infarction., (Copyright 2009 S. Karger AG, Basel.)

Gaucher disease is a recessively inherited lysosomal storage disorder, caused by deficiency of glucocerebrosidase activity. Affected individuals usually present with hepatosplenomegaly, anaemia, thrombocytopenia, and skeletal diseases. A wide range of neurological manifestations have also been recognized in Gaucher patients including acute neurological deterioration in infancy, mental retardation, ocular motor apraxia, seizure, and parkinsonism. Although muscle weakness is not an uncommon finding in patients with Gaucher disease, the aetiology of weakness is not well understood. We prospectively investigated seven Gaucher patients and found that four of them (patients 1-4) had mild to moderate degree of proximal-predominant symmetrical muscle weakness in four limbs. By history, three patients (patients 1-3) developed insidious onset of nonprogressive muscle weakness in four limbs with easy muscle fatigue from adolescence. A needle electromyographic study detected some small, brief polyphasic waves in these four patients. Muscle biopsy in one patient (patient 1) showed a few atrophic type II muscle fibres without infiltration of Gaucher cells. Three patients (patients 1-3) continuously received enzyme replacement therapy with imiglucerase and their muscle strength seemed improved after two years. We concluded that Gaucher disease may be associated with myopathy.

Spinal muscular atrophy (SMA) is a progressive disease involving the degeneration of motor neurons with no currently available treatment. While valproic acid (VPA) is a potential treatment for SMA, its therapeutic mechanisms are still controversial. In this study, we investigated the mechanisms of action of VPA in the treatment of type III-like SMA mice. SMA and wild-type mice were treated with VPA from 6 to 12 months and 10 to 12 months of age, respectively. Untreated SMA littermates and age-matched wild-type mice were used for comparison. VPA-treated SMA mice showed better motor function, larger motor-evoked potentials, less degeneration of spinal motor neurons, less muscle atrophy, and better neuromuscular junction innervation than non-treated SMA mice. VPA elevated SMN protein levels in the spinal cord through SMN2 promoter activation and probable restoration of correct splicing of SMN2 pre-messenger RNA. VPA also increased levels of anti-apoptotic factors, Bcl-2 and Bcl-x(L), in spinal neurons. VPA probably induced neurogenesis and promoted astrocyte proliferation in the spinal cord of type III-like SMA mice, which might contribute to therapeutic effects by enhancing neuroprotection. Through these effects of elevation of SMN protein level, anti-apoptosis, and probable neuroprotection, VPA-treated SMA mice had less degeneration of spinal motor neurons and better motor function than untreated type III-like SMA mice.

Currently, no curative treatment is available for spinal muscular atrophy (SMA). Since the degeneration of spinal motor neurons in SMA is mediated by apoptosis, over-expression of an anti-apoptotic factor, Bcl-x(L), may benefit SMA. Here, we crossed a mouse model of SMA with Bcl-x(L) transgenic mice to create SMA/Bcl-x(L) mice. The Bcl-x(L) expression in the spinal neurons of SMA/Bcl-x(L) mice was nearly double that in SMA mice. SMA/Bcl-x(L) mice showed preserved motor function, normalized electrophysiological tests, diminished muscle atrophy, and less motor neuron degeneration. In addition, the life span of SMA/Bcl-x(L) mice was 1.5 times longer than that of SMA mice. Therefore, over-expression of Bcl-x(L) has a potential for amelioration of SMA, and Bcl-x(L) may be another attractive therapeutic target other than survival motor neuron (SMN) protein for use in future drug screening for SMA.

Niemann-Pick disease type C (NP-C) is a lipid storage disorder characterized by the accumulation of unesterified cholesterol and glycolipids in the lysosomal/late endosomal system of certain cells in the central nervous system (CNS) and visceral organs. Clinical symptoms include progressive neurological deterioration and visceral organomegaly. Miglustat, a small iminosugar molecule approved for the treatment of Gaucher disease, reversibly inhibits glucosylceramide synthase, which catalyses the first committed step in glycosphingolipid synthesis. The physicochemical properties of miglustat allow it to cross the blood-brain barrier and suggest possible benefits in lysosomal storage diseases affecting the CNS. Here, we present findings in two children with NP-C, aged 14 years (patient 1) and 9 years (patient 2), treated with miglustat for 1 year. Before treatment, patient 1 presented with severe difficulties in swallowing and walking, and patient 2 with problems mostly affecting communication and social interaction. Videofluoroscopic studies in patient 1 demonstrated a substantial improvement in swallowing by month 6 of treatment, and ambulation index measurements indicated improved walking. Mini Mental-State Examination (MMSE) assessments in patient 2 showed cognitive improvement by month 6, which was sustained up to month 12. Liver/spleen volume and plasma chitotriosidase activities were stabilized in both cases. There was no weight loss during treatment. Patient 1 experienced severe but self-limiting paresthesia, which was not associated with peripheral neuropathy. We conclude that miglustat can provide therapeutic benefits in CNS symptoms and allows stabilization of systemic disease in childhood-onset NP-C. Further follow-up is crucial to determine the long-term maintenance of these effects.

Several mice models have been created for spinal muscular atrophy (SMA); however, there is still no standard preclinical testing system for the disease. We previously generated type III-specific SMA model mice, which might be suitable for use as a preclinical therapeutic testing system for SMA. To establish such a system and test its applicability, we first created a testing protocol and then applied it as a means to investigate the use of valproic acid (VPA) as a possible treatment for SMA. These SMA mice revealed tail/ear/foot deformity, muscle atrophy, poorer motor performances, smaller compound muscle action potential and lower spinal motoneuron density at the age of 9 to 12 months in comparison with age-matched wild-type littermate mice. In addition, VPA attenuates motoneuron death, increases spinal SMN protein level and partially normalizes motor function in SMA mice. These results suggest that the testing protocol developed here is well suited for use as a standardized preclinical therapeutic testing system for SMA.

Although retrograde gene transfer from infected muscles to neurons by viral vectors has been known for years, it is still unknown whether interneuronal gene transportation of viral vectors occurs after retrograde gene transfer. To determine this, we injected adenoviral vectors carrying eGFP gene with or without a neural tracer into the right gastrocnemius muscles of mice. After 7 days, some spinal motor neurons were detected with green fluorescence but without the signal of neural tracer. In addition, nerves with green fluorescence could be noted in the right lumbosacral paraspinal muscles of viral-injected mice. The green fluorescence in the right lumbosacral paraspinal muscles might have resulted from retrograde gene transportation from the viral-injected gastrocnemius muscles to the spinal neurons, followed by interneuronal transfer and anterograde expression of eGFP in the axons belonging to neurons innervating the paraspinal muscles. This phenomenon of interneuronal transportation raises the possibility that we could treat motoneuron diseases by injection of viral vectors containing therapeutic genes into a few muscles resulting in widespread beneficial effects.

During the worldwide outbreak of severe acute respiratory syndrome (SARS) in 2002-2003, there were 664 probable SARS patients reported in Taiwan. SARS patients usually present with symptoms related to the respiratory system while neurological manifestations have rarely been described. There were three patients who developed axonopathic polyneuropathy 3-4 weeks after onset of SARS; their clinical condition and electrophysiological studies revealed obvious improvement at follow-up. Two SARS patients have experienced myopathy and three other patients developed rhabdomyolysis. These neuromuscular disorders in SARS patients were considered as critical illness neuropathy and myopathy, but the possibility of direct attack by SARS coronavirus on the nerve and muscle could not be excluded. Large artery ischemic stroke were described in five SARS patients with poor prognosis. Multiple factors contributed to this vascular insult included hypercoagulabe status related to both SARS coronavirous and the usage of intravenous immunoglobulin, septic and cardiogenic shock, and possible vasculitis. The relationship between SARS and above neurological problems still needs further clarification. Pathological and microbiological studies are mandatory to delineate this issue.

Background and Purpose: Studies to determine the value of noninvasive neurovascular studies for the effectiveness of treatment and long-term follow-up of dural arteriovenous fistulas (AVFs) are of clinical importance. We determined whether the serial changes of carotid duplex sonography (CDS) were correlated with the evolution of dural AVF status after treatment or follow-up., Methods: Four parameters of CDS were studied in two groups of patients with dural AVF: resistance index, end diastolic velocity, peak systolic velocity, and flow volume of the external carotid artery (ECA). The first group included 13 patients who received endovascular therapy, the efficacy of which was determined by the results of postembolization angiography. In the second group, 16 patients received only clinical and CDS follow-up. Evolution of clinical symptoms was recorded and classified as deteriorating, stationary, or improving. Patients underwent CDS before and after treatment (group 1) or at long-term follow-up (group 2)., Results: In the first group, the resistance index of the ECA increased in patients with occluded or nearly occluded dural AVF after embolization (n = 7, P = .01), but it did not change significantly in patients with partial treatment (n = 6, P = .11). Of patients with occluded or nearly occluded dural AVF after embolization, the ECA resistance index increased in patients with noncavernous sinus dural AVF (n = 5, P = .003) but not in patients with cavernous sinus dural AVF (n = 2, P = .48). In the second group, CDS parameters-particularly the resistance index-were well correlated with clinical status during follow-up., Conclusion: The resistance index of the ECA is correlated with the effectiveness of treatment and clinical evolution of dural AVF.

Objective: To delineate and clarify neuromuscular disorders in patients with probable severe acute respiratory syndrome (SARS)., Design: Case series with follow-up ranging from 3 weeks to 2 months., Setting: National Taiwan University Hospital, Taipei., Patients: We investigated 4 patients with SARS who had concomitant neuromuscular problems. A diagnosis of SARS was based on the demonstration of serum coronavirus antibodies. Clinical presentations, laboratory results, electrophysiologic findings, and follow-up conditions were determined., Results: Patients developed neuromuscular problems approximately 3 weeks after the onset of SARS. Two women experienced motor-predominant peripheral nerve disorders. A man developed myopathy and a third woman experienced neuropathy and myopathy. Cerebrospinal fluid obtained from 2 patients with neuropathy disclosed normal protein content and the absence of pleocytosis and SARS coronavirus antibodies. Both patients with myopathy had elevated serum creatine kinase levels. A rapid clinical and electrophysiologic improvement was evident during follow-up examinations, with a good prognosis., Conclusions: The neuromuscular problems in patients with SARS are considered to be critical-illness polyneuropathy or myopathy, possibly coexistent. Further pathological and microbiological studies are necessary to determine the relationship between SARS coronavirus and neuromuscular problems.

Objectives: To compare the characteristics of dural arteriovenous fistulas (AVFs) with or without cerebral sinus thrombosis (CST), and to analyse the determinants of aggressive manifestations in patients with dural AVF., Methods: We investigated 69 patients aged 51.4 (SD 15) years who were diagnosed as having dural AVF. According to the location of the lesion and venous drainage pattern, dural AVF was classified into three sites (cavernous sinus, large sinus, and other) and five types (by Cognard's method). Aggressive manifestations of dural AVF were defined as intracranial haemorrhage, venous infarction, seizure, altered mental status, and intracranial hypertension. The diagnosis of CST was based on cerebral angiography. Logistic regression methods were used to analyse the determinants of aggressive manifestation in patients with dural AVF., Results: CST was found in 39% of the patients with dural AVF. It was located at almost either the sinus around the dural AVF or the downstream venous flow pathways of the dural AVF. There was no significant difference with regard to sex, location, or type of dural AVF between patients with dural AVF with and without CST. The location "other sinuses" and the type of dural AVF "IIb/IIa+b/III/IV/V" were significantly related to aggressive manifestations of dural AVF (odds ratio 19 (p = 0.001) and 5.63 (p = 0.033), respectively). Presence of CST in patients with dural AVF had an odds ratio of 4.25 (p = 0.12) for development of aggressive manifestations., Conclusions: CST affects two fifths of patients with dural AVF. The location and type of dural AVF are major determinants of aggressive manifestations in patients with dural AVF.

Objective: To validate carotid duplex sonography (CDS) in diagnosis of intracranial dural arteriovenous fistulas (AVFs) against the standard of cerebral catheter angiography., Methods: We investigated 35 patients with dural AVFs and 64 patients without dural AVFs confirmed by the catheter angiographic studies. Twenty CDS parameters in 4 categories, including resistive index (RI), flow volume, peak systolic velocity, and end-diastolic velocity, were evaluated. Abnormal CDS findings were defined as the data above 95th percentile or below 5th percentile values from 180 control subjects. We determined the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in each CDS parameter., Results: The parameter of RI of the external carotid artery (ECA; cutoff points: right, 0.72; left, 0.71) yielded the highest sensitivity (74%), specificity (89%), positive predictive value (79%), negative predictive value (86%), and accuracy (84%) for predicting dural AVFs. All other ECA-related parameters yielded sensitivity lower than 70%, and those related to the internal carotid artery were lower than 30%. The sensitivity values for the parameter of RI of the ECA in different locations of dural AVFs were 54% (7 of 13 patients) in cavernous sinus dural AVFs and 86% (19 of 22 patients) in non-cavernous sinus dural AVFs (P = .05)., Conclusions: The RI of the ECA is the best CDS parameter for predicting intracranial dural AVFs. Carotid duplex sonography can be used as the initial screening tool for diagnosis in patients having symptoms related to dural AVFs.

The Candida albicans gene EFG1 encodes a putative trans-acting factor. In strain WO-1, which undergoes the white-opaque transition, EFG1 is transcribed as a 3.2-kb mRNA in white-phase cells and a less-abundant 2.2-kb mRNA in opaque-phase cells. cDNA sequencing and 5' rapid amplification of cDNA ends analysis demonstrate that the major difference in molecular mass of the two transcripts is due to different transcription start sites. EFG1 null mutants form opaque-phase colonies and express the opaque-phase cell phenotype at 25 degrees C. When shifted from 25 to 42 degrees C, mutant opaque-phase cells undergo phenotypic commitment to the white phase, which includes deactivation of the opaque-phase-specific gene OP4 and activation of the white-phase-specific gene WH11, as do wild-type opaque-phase cells. After the commitment event, EFG1 null mutant cells form daughter cells which have the smooth (pimpleless) surface of white-phase cells but the elongate morphology of opaque-phase cells. Taken together, these results demonstrate that EFG1 expression is not essential for the switch event per se, but is essential for a subset of phenotypic characteristics necessary for the full expression of the phenotype of white-phase cells. These results demonstrate that EFG1 is not the site of the switch event, but is, rather, downstream of the switch event.

Although Candida glabrata has emerged in recent years as a major fungal pathogen, there have been no reports demonstrating that it undergoes either the bud-hypha transition or high-frequency phenotypic switching, two developmental programs believed to contribute to the pathogenic success of other Candida species. Here it is demonstrated that C. glabrata undergoes reversible, high-frequency phenotypic switching between a white (Wh), light brown (LB), and dark brown (DB) colony phenotype discriminated on an indicator agar containing 1 mM CuSO(4). Switching regulates the transcript level of the MT-II metallothionein gene(s) and a newly discovered gene for a hemolysin-like protein, HLP. The relative MT-II transcript levels in Wh, LB, and DB cells grown in the presence of CuSO(4) are 1:27:81, and the relative transcript levels of HLP are 1:20:35. The relative MT-II and HLP transcript levels in cells grown in the absence of CuSO(4) are 1:20:30 and 1:20:25, respectively. In contrast, switching has little or no effect on the transcript levels of the genes MT-I, AMT-I, TRPI, HIS3, EPAI, and PDHI. Switching of C. glabrata is not associated with microevolutionary changes identified by the DNA fingerprinting probe Cg6 and does not involve tandem amplification of the MT-IIa gene, which has been shown to occur in response to elevated levels of copper. Finally, switching between Wh, LB, and DB occurred in all four clinical isolates examined in this study. As in Candida albicans, switching in C. glabrata may provide colonizing populations with phenotypic plasticity for rapid responses to the changing physiology of the host, antibiotic treatment, and the immune response, through the differential regulation of genes involved in pathogenesis. More importantly, because C. glabrata is haploid, a mutational analysis of switching is now feasible.

Candida albicans strain WO-1 undergoes two developmental programs, the bud-hypha transition and high-frequency phenotypic switching in the form of the white-opaque transition. The WH11 gene is expressed in the white budding phase but is inactive in the white hyphal phase and in the opaque budding phase. WH11 expression, therefore, is regulated in the two developmental programs. Through fusions between deletion derivatives of the WH11 promoter and the newly developed Renilla reniformis luciferase, the WH11 promoter has been characterized in the two developmental programs. Three transcription activation sequences, two strong and one weak, are necessary for the full expression of WH11 in the white budding phase, but no negative regulatory sequences were revealed as playing a role in either the white hyphal phase or the opaque budding phase. These results suggest that regulation is solely through activation in the white budding phase and the same mechanism, therefore, is involved in regulating the differential expression of WH11 in the alternative white and opaque phases of switching and the budding and hyphal phases of dimorphism.

The infectious yeast Candida albicans progresses through two developmental programs which involve differential gene expression, the bud-hypha transition and high-frequency phenotypic switching. To understand how differentially expressed genes are regulated in this organism, the promoters of phase-specific genes must be functionally characterized, and a bioluminescent reporter system would facilitate such characterization. However, C. albicans has adopted a nontraditional codon strategy that involves a tRNA with a CAG anticodon to decode the codon CUG as serine rather than leucine. Since the luciferase gene of the sea pansy Renilla reinformis contains no CUGs, we have used it to develop a highly sensitive bioluminescent reporter system for C. albicans. When fused to the galactose-inducible promoter of GAL1, luciferase activity is inducible; when fused to the constitutive EF1 alpha 2 promoter, luciferase activity is constitutive; and when fused to the promoter of the white-phase-specific gene WH11 or the opaque-phase-specific gene OP4, luciferase activity is phase specific. The Renilla luciferase system can, therefore, be used as a bioluminescent reporter to analyze the strength and developmental regulation of C. albicans promoters.

Thirty ASA class I female patients underwent gynecologic pelvioscopy and laparoscopic cholecystectomy were included in this study. All of them received general anesthesia and certain volume of CO2 pneumoperitoneum. We evaluated the effect of positioning (Trendelenburg as group I and reverse Trendelenburg as group II) on hemodynamic parameters and ventilation. The hemodynamic parameters, ventilation, and arterial blood gas were determined at the following stages: (1) after 10 minutes of normoventilation and before CO2 pneumoperitoneum (as control), (2) 5 minutes after CO2 pneumoperitoneum and positioning, (3) 25 minutes after positioning, (4) 50 minutes after positioning, (5) 10 minutes after resumption of supine position and decompression of abdomen. Arterial blood pressure, heart rate, minute volume, end-tidal CO2, oxygen saturation and blood gas analysis were taken during normoventilation. We found that there was no statistical difference between either group in respect to hemodynamic parameters. For the ventilation, both groups had appropriate SpO2 during the period of CO2 pneumoperitoneum, but PaCO2 was significantly increased in group I 25 min after CO2 pneumoperitoneum and Trendelenburg positioning. Nonetheless, end-tidal CO2 was not significantly increased. pH value and PaCO2 did respectively decrease and increase significantly in group I 50 min after Trendelenburg position. However, no change was found in end-tidal CO2. All data were not significantly different after resumption of supine position and decompression of abdomen. Conclusively, except that pH and PaCO2 had changed after a period of Trendelenburg positioning with CO2 pneumoperitoneum, the patients who underwent laparoscopic surgery with normoventilation have no hemodynamic and respiratory change.(ABSTRACT TRUNCATED AT 250 WORDS)