Clozapine in the treatment of neuroleptic-induced blepharospasm: a report of 4 cases

BACKGROUND

Blepharospasm, the forcible closure of eyelids, is an infrequent consequence of neuroleptic treatment that, when severe, can interfere with the ability to walk, drive, or work. Like tardive dyskinesia, blepharospasm can be disfiguring and aesthetically distressing, contributing to the increased stigmatization of patients.

CASE REPORTS

We report 4 patients with DSM-IV schizoaffective disorder, paranoid schizophrenia, or chronic undifferentiated schizophrenia who developed neuroleptic-induced blepharospasm. In all patients, blepharospasm remitted without the reemergence of psychosis within 3 to 5 months of treatment with clozapine, 100-200 mg/day.

CONCLUSION

The results suggest that clozapine may successfully treat neuroleptic-induced blepharospasm without the reemergence of psychosis in patients with schizophrenia, schizoaffective disorder, or schizophreniform disorder.

Demonstration of a compact compressor for application of metastability-exchange optical pumping of 3He to human lung imaging

Hyperpolarized gas magnetic resonance imaging has recently emerged as a method to image lungs, sinuses, and the brain. The best lung images to date have been produced using hyperpolarized 3He, which is produced by either spin-exchange or metastability-exchange optical pumping. For hyperpolarized gas MRI, the metastable method has demonstrated higher polarization levels and higher polarizing rates, but it requires compression of the hyperpolarized gas. Prior to this work, compression of hyperpolarized gas had only been accomplished using a large, complex and expensive apparatus. Here, human lung ventilation images are presented that were obtained using a compact compressor that is relatively simple and inexpensive. For this test, 1.1 bar-L of 15% hyperpolarized 3He gas was produced at the National Institute of Standards and Technology using a modified commercial diaphragm pump. The hyperpolarized gas was transported to the University of Pennsylvania in a holding field provided by a portable solenoid.

A phase I/II study of recombinant human interleukin-12 in patients with chronic hepatitis B

BACKGROUND/AIMS

Interleukin-12 (IL-12) may be active against hepatitis B virus (HBV). The objective of the study was to assess the tolerability, activity, pharmacokinetics, and pharmacodynamics of three dose levels (0.03 microg/kg b.w., n=15; 0.25 microg/kg b.w., n=15; 0.50 microg/kg b.w., n=16) of recombinant human (rHu) IL-12 given s.c. once a week for 12 consecutive weeks.

METHODS

Forty-six patients with chronic hepatitis B, HBV DNA positivity and aminotransferase elevation were included in a multicenter prospective randomized phase I/II study.

RESULTS

Compared with the baseline, HBV DNA levels had decreased significantly at the end of rHuIL-12 treatment and after the 12-week follow-up period (p<0.001). The response to rHuIL-12 treatment was dose-dependent: at the end of the study HBV DNA clearance was greater in patients treated with 0.50 microg/kg b.w. (25%) or with 0.25 microg/kg b.w. (13%) compared with those given 0.03 microg/kg b.w. (7%). Moreover, HBeAg became undetectable at the end of follow-up in five of the patients given the 0.25microg/kg (2/15) or the 0.50 microg/kg (3/16) dose. The drug pharmacology showed that IL-12 had an estimated half-life of 30 h with levels remaining detectable for more than 48 h after rHuIL-12 administration. The serum levels of IL-12, interferon-gamma, IL-10, neopterin and beta2-microglobulin as well as the area under the curve (AUC) were rHuIL-12 dose-related. Side effects were observed more frequently with higher doses, including moderate decreases in lymphocyte and neutrophil counts; three patients withdrew prematurely from treatment. The local reaction observed at the injection site was unrelated to the drug dose. Only one patient showed detectable antibody levels to rHuIL-12 without clinical impact.

CONCLUSIONS

Treatment with rHuIL-12 at the doses investigated is safe and tolerable, and appears to be active against HBV in patients with chronic hepatitis B.

Sodium visibility and quantitation in intact bovine articular cartilage using high field (23)Na MRI and MRS

Noninvasive methods of detecting cartilage degeneration can have an impact on identifying the early stages of osteoarthritis. Accurate measurement of sodium concentrations within the cartilage matrix provides a means for analyzing tissue integrity. Here a method is described for quantitating sodium concentration and visibility in cartilage, with general applications to all tissue types. The sodium concentration in bovine patellar cartilage plugs was determined by three different methods: NMR spectroscopy of whole cartilage plugs, NMR spectroscopy of liquefied cartilage in concentrated HCl, and inductively coupled plasma emission spectroscopy. Whole bovine patellae were imaged with relaxation normalized calibration phantoms to ascertain sodium concentrations inside the articular cartilage. Sodium concentrations in intact articular cartilage were found to range from approximately 200 mM on the edges to approximately 390 mM in the center, with an average of approximately 320 mM in five separate bovine patellae studied. In essence, we have created sodium distribution maps of the cartilage, showing for the first time, spatial variations of sodium concentration in intact cartilage. This average concentration measurement correlates very well with the values obtained from the spectroscopic methods. Furthermore, sodium was found to be 100% NMR visible in cartilage plugs. Applications of this method in diagnosing and monitoring treatment of osteoarthritis are discussed.

Odorants induce the phosphorylation of the cAMP response element binding protein in olfactory receptor neurons

Although odorants are known to activate olfactory receptor neurons through cAMP, the long-term effects of odorant detection are not known. Our recent findings indicate that there is also a delayed and sustained cAMP response, with kinetics sufficient to mediate long-term cellular responses. This cAMP response is mediated by cGMP through activation of adenylyl cyclase by protein kinase G (PKG). Therefore, we investigated the ability of odorants to regulate gene expression in rat olfactory epithelium. The cAMP-responsive binding protein (CREB) is a well-characterized transcription factor regulated by cAMP. We examined CREB activity in rat olfactory epithelium and olfactory receptor neurons (ORNs) after stimulation with odorants. Odorants increased levels of phosphorylated CREB in olfactory epithelium in vivo, and this increase was localized to ORNs in vitro. Incubation with 8-bromo-cGMP or sodium nitroprusside, a guanylyl cyclase activator, also increased phosphorylated CREB. In vitro, cAMP-dependent protein kinase phosphorylated CREB. In contrast, PKG failed to phosphorylate CREB directly in vitro. Our results demonstrate that the delayed odorant-induced cAMP signal activates CREB, which in turn may modulate gene expression in ORNs. In addition, cGMP indirectly affects CREB activation. This effect of cGMP on CREB activity through cAMP provides another mechanism for the modulation of CREB.

Sodium and proton MR properties of cartilage during compression

Proton and sodium MR relaxation times of bovine articular cartilage specimens were measured as a function of proteoglycan (PG) depletion and as a function of mechanical compression. Proton and sodium relaxation times of normal cartilage were compared with relaxation times of PG-depleted cartilage to evaluate the significance of PG depletion-induced changes in MR relaxation parameters. These comparisons were conducted for both uncompressed and mechanically compressed states. The mechanical compressions were performed with an MR-compatible pressure cell and evaluated dynamically via interleaved one-dimensional proton and sodium MR projection imaging. The comparisons indicate that sodium relaxation parameters are sensitive to PG depletion when cartilage is in a mechanically compressed state or an uncompressed state. In contrast, proton relaxation parameters do not change significantly with PG depletion when cartilage is in an uncompressed state. However, during mechanical compression, proton T2 becomes sensitive to PG depletion. These results support the potential of sodium magnetic resonance imaging (MRI) as a possible modality for obtaining imaging contrast related to PG depletion. The results also indicate the potential of proton MRI to provide such contrast if the image acquisition is conducted in conjunction with a mechanical compression via physical exercise.J. Magn. Reson Imaging 10:961-967, 1999.

In vivo triple quantum filtered twisted projection sodium MRI of human articular cartilage

In this work, we present the first triple quantum filtered (TQF) sodium MR images of the human knee joint in vivo. A 3D TQF data set of 16 slices was obtained in 20 min using a TQF pulse sequence preencoded to a twisted projection imaging readout. Images clearly demarcate patellar cartilage and also demonstrate fluid signal suppressed by the triple quantum filter. Biexponential transverse relaxation times were calculated by fitting the TQF free induction decay to a theoretical signal expression. The average values from three healthy volunteers were T(2fall)(*) = 9.59 +/- 0.35 ms and T(2rise)(*) = 0.84 +/- 0.06 ms. Application of TQF imaging in biological tissues is discussed.

An RNA polymerase III transcription unit located in the upstream control regions of the human proliferating-cell nucleolar protein p120 gene is transcribed in vitro and in vivo

An RNA polymerase III (Pol III) transcription unit containing homology to highly repeated Alu sequences was identified in the upstream flanking sequences of the gene for the human proliferating-cell nucleolar antigen p120. When transcribed in vitro, this Pol III unit produced three RNA transcripts, designated by nucleotide length as T150, T385 and T635; RNA transcript T635 was the most abundant accounting for over 90%. The transcription initiates at nucleotide -729 of the human p120 promoter and proceeds in the opposite orientation to the p120 gene transcription. Northern blot analysis and cDNA cloning followed by sequencing showed the presence of the T635 RNA in HeLa cells, indicating that this Pol III transcription unit is functional and transcribed in vivo. Disruption of this Pol III transcription unit by deletion of the Box A residues (-733 to -744) resulted in a sixfold reduction of the p120 gene transcription. A possible role for this Pol III transcription unit in p120 gene transcription is discussed.

Post-transcriptional adenylation of signal recognition particle RNA is carried out by an enzyme different from mRNA Poly(A) polymerase

A fraction of the signal recognition particle (SRP) RNA from human, rat, Xenopus, and Saccharomyces cerevisiae cells contains a single post-transcriptionally added adenylic acid residue on its 3'-end; in the case of human SRP RNA, over 60% of the SRP RNA molecules contain a nontemplated adenylic acid residue on their 3'-ends (Sinha, K. M., Gu, J., Chen, Y., and Reddy, R. (1998) J. Biol. Chem. 273, 6853-6859). In this study, we investigated the enzyme that is involved in this 3'-end adenylation of SRP RNA. A U1A protein peptide conjugated to albumin completely inhibited the polyadenylation of a SV40 mRNA by HeLa cell nuclear extract in vitro; however, the 3'-end adenylation of human SRP RNA or Alu RNA, which corresponds to 5' and 3'-ends of SRP RNA, was not affected by this U1A peptide conjugate. SRP RNA from mutant strains of S. cerevisiae with a temperature-sensitive mRNA poly(A) polymerase grown at a restrictive temperature of 37 degrees C also contained a post-transcriptionally added adenylic acid residue just like SRP RNA from wild-type cells and mutant cells grown at permissive temperature of 23 degrees C. In addition, binding of SRP 9/14-kDa protein heterodimer was required for adenylation of Alu RNA in vitro. These lines of evidence, along with other data, show that post-transcriptional adenylation of SRP and Alu RNAs is carried out by a novel enzyme that is distinct from the mRNA poly(A) polymerase, CCA-adding enzyme, and nonspecific terminal transferase.

Pseudo-outbreak of methicillin-resistant Staphylococcus aureus

OBJECTIVE

To determine whether a high rate of methicillin-resistant Staphylococcus aureus at our institution was due to laboratory misclassification and to evaluate the effect of this misclassification.

MATERIAL AND METHODS

We evaluated all S. aureus isolates identified at our institution during a 60-day period in 1997. Automated susceptibility test results (using the Vitek system) from our clinical microbiology laboratory and an independent laboratory were compared with oxacillin agar screen plate results at both laboratories. Isolates with discordant results for susceptibility to oxacillin were tested by broth microdilution minimal inhibitory concentrations and for the presence of the mecA gene.

RESULTS

Eighteen (72%) of the 25 organisms (obtained from 17 patients) found to be resistant to oxacillin by the Vitek system at our institution were susceptible by the oxacillin agar screen. Discordant isolates tested by broth microdilution minimal inhibitory concentrations and for the mecA gene were found to be oxacillin susceptible and mecA gene negative. Thus, at our hospital, almost three fourths of the organisms initially identified as methicillin-resistant S. aureus by the Vitek system were actually susceptible to oxacillin. This misclassification resulted in needless infection control measures and unnecessary vancomycin use.

CONCLUSION

Hospitals that use only automated susceptibility testing for S. aureus should periodically validate their results with additional testing.

Acute myo-inositol enhances swimming activity in goldfish (short communication)

Inositol in concentrations of 1-4 Mm (but not the control condition: mannitol-glucose) administered in aquarium water showed enhancement of swimming activity of goldfish after acute treatment (5 hours). These data support similar findings in rats. These data suggest that inositol may enhance motor activity which may be of relevance in neuropsychiatric disorders. Future studies of the effects of lithium on this activity, and its potential reversal by inositol may shed light on the possible involvement of the phosphatidyl-inositol second messenger system in this behavior.

Metronidazole and clarithromycin resistance amongst Helicobacter pylori isolates from a large metropolitan hospital in the United States

BACKGROUND

Metronidazole and clarithromycin-based therapies are among the most efficacious treatment regimens for H. pylori infection. Resistance to metronidazole or clarithromycin is associated with impaired therapy with these agents. We conducted a retrospective review of susceptibility data to determine the frequency of primary metronidazole and clarithromycin resistance among H. pylori isolates from a single metropolitan hospital in the United States. The database comprised 933 patients who presented at the Digestive Diseases Clinic at the Veterans Affairs Medical Center in Houston between September 1988 and January 1997 with complaints of dyspepsia, abdominal pain and peptic ulcer disease. One hundred and seventy-nine of these patients had both pharmaceutical records available for evaluation and culture and antimicrobial susceptibility data for analysis. The MICs were determined by both E-test and broth microdilution tests. The frequency of primary metronidazole resistance was 37.4% (67/179). The level of primary clarithromycin resistance was 6.1%. Dual metronidazole and clarithromycin resistance was present in approx. 3%. The high level of primary metronidazole and clarithromycin resistance in H. pylori isolates from this metropolitan hospital is such that antimicrobial susceptibility data should be available so that informed choice can be made for specific eradication therapies, especially in patients who fail treatment.

Hepatitis C virus genotypes and viremia and hepatocellular carcinoma in the United States

OBJECTIVE

Hepatitis C virus (HCV) is a well recognized cause of hepatocellular carcinoma (HCC). The pathogenic significance of HCV genotypes in hepatocarcinogenesis is undefined. The aim of this study was to investigate the genotypic distribution and viremic level of HCV in patients with HCV-associated cirrhosis with or without HCC.

METHODS

A total of 28 HCV-infected patients with HCC (HCC+) and 38 patients with HCV-associated cirrhosis without HCC (HCC-) were studied. HCV genotype was assessed by the genotype-specific polymerase chain reaction (PCR) method of Okamoto and restriction fragment length polymorphism (RFLP) of the 5' untranslated region (5' UTR). Hepatitis C viremia was quantitated with the branched-chain DNA (bDNA) assay.

RESULTS

Using the Okamoto method, we found genotype 1b in 64% of the HCC+ group and 74% of the HCC- group, 36% of the HCC+ group and 16% of the HCC- group were coinfected with a combination of genotype 1b and another genotype. Using the RFLP method, we found genotype 1b in 41% of the HCC+ group and in 24% of the HCC- group. Other genotypes accounted for 18% of the HCC+ group and 55% of the HCC- group; no combination genotypes were identified. Poor concordance occurred between the two genotyping methods. Mean bDNA levels were not significantly different between the two groups.

CONCLUSIONS

Our study demonstrates that no particular HCV genotypes were associated with HCC and genotype did not appear to influence the development of HCV-associated HCC.

A novel approach to observing articular cartilage deformation in vitro via magnetic resonance imaging

The design of a pressure cell that compresses a cartilage specimen in one dimension within an imaging magnet is presented. One-dimensional projection images in a direction perpendicular to the articular surface of the cartilage specimen were used to generate a uniaxial confined deformation creep curve for normal and trypsin-degraded cartilage specimens during a continuous 0.690 MPa (100 psi) pressure application. The resulting curves are shown to fit a two time constant viscoelastic model well and also indicate that the elastic modulus of cartilage decreases and the deformation rate increases upon trypsin proteolysis. Furthermore, cartilage permeability is shown as a function of cartilage strain for both the normal and trypsin-degraded case. Several two-dimensional slice-selective images were collected both before and after 80 minutes of continuous compression. These images were used to evaluate the relative changes in the spin-lattice, T1, and spin-spin, T2, relaxation time constant maps for both normal and degraded cartilage specimens in response to compression. The results of this study demonstrate the utility of a novel, non-magnetic, cartilage compression device and also support the validity of a simple two-component rheological model of articular cartilage.

Bcl-2 and p53 immunoprofile in Kaposi's sarcoma

Seventy three cases of Kaposi's sarcoma (KS) from the 3 histological subtypes (patch, plaque and nodular) were assessed for bcl-2 and p53 protein expression. The aim was to determine the level of expression of these proteins in KS and in the different subtypes. Commercially available antibodies to bcl-2 and p53 were applied after both microwave and pressure cooking antigen retrieval. Bcl-2 immunoexpression increased from the patch stage (36%) to the plaque stage (45%) to the nodular stage (70.83%). Better immunostaining for bcl-2 was obtained after pressure cooking. p53 on the other hand, was not expressed in the patch or plaque stages, but 54.16% of cases in the nodular stage were immunopositive. These results show a progression of immunoexpression of both bcl-2 and p53 from the early histological stages to the late tumor stage, implying that these proteins are upregulated late in the evolution of KS.

Detection of residual quadrupolar interaction in the human breast in vivo using sodium-23 multiple quantum spectroscopy

Sodium multiple quantum (MQ) spectroscopy of the human breast in vivo was performed. Double quantum (DQ) filtered spectra were used to demonstrate the existence of a non-vanishing (residual) quadrupolar interaction in the tissue. Triple quantum (TQ) filtered spectra were used to measure the two time constants associated with the biexponential transverse relaxation times of sodium in biological tissues. The two time constants were found to be 0.64 and 26.57 msec. The potential applications of this finding are discussed.

An MR imaging method for simultaneous measurement of gaseous diffusion constant and longitudinal relaxation time

A magnetic resonance imaging method for simultaneous and accurate determination of gaseous diffusion constant and longitudinal relaxation time is presented. The method is based on direct observation of diffusive motion. Initially, a slice-selective saturation of helium-3 (3He) spins was performed on a 3He/O2 phantom (9 atm/2 atm). A time-delay interval was introduced after saturation, allowing spins to diffuse in and out of the labeled slice. Following the delay interval a one-dimensional (1-D) projection image of the phantom was acquired. A series of 21 images was collected, each subsequent image having been acquired with an increased delay interval. Gradual spreading of the slice boundaries due to diffusion was thus observed. The projection profiles were fit to a solution of the Bloch equation corrected for diffusive motion. The fitting procedure yielded a value of D3He = 0.1562+/-0.0013 cm2/s, in good agreement with a measurement obtained with a modified version of the standard pulsed-field gradient technique. The method also enabled us to accurately measure the longitudinal relaxation of 3He spins by fitting the change of the total area under the projection profiles to an exponential. A value of T1 = 1.67 s (2 T field) was recorded, in excellent agreement with an inversion recovery measurement.

Sodium NMR evaluation of articular cartilage degradation

One of the first effects of degenerative osteoarthritis is the loss of proteoglycans from the matrix of articular cartilage. Using a model of osteoarthritic change where the cartilage has been enzymatically degraded with trypsin, the sodium NMR characteristics of the cartilage were determined as a function of changes in the proteoglycan content. The results demonstrate that the single quantum sodium signal decreases as the proteoglycan content of the cartilage matrix decreases. In addition, the relaxation characteristics of the sodium change such that the T1 is longer, the T2s is longer, and the T2f is shorter. Short echo-time, T1-weighted sodium images are presented which demonstrate that this information may be utilized to detect the loss of proteoglycans from articular cartilage.

Accurate 3' end processing and adenylation of human signal recognition particle RNA and alu RNA in vitro

Human signal recognition particle (SRP) RNA is transcribed by RNA polymerase III and terminates with -GUCUCUUUUOH on its 3' end. Our previous studies showed that the three terminal uridylic acid residues of human SRP RNA are post-transcriptionally removed and a single adenylic acid residue is added, resulting in a 3' end sequence of -GUCUCUAOH (Sinha, K. M., Gu, J., Chen, Y., and Reddy, R. (1998) J. Biol. Chem. 273, 6853-6859). In this study we show that the Alu RNA, corresponding to the 5' and 3' ends of SRP RNA, is also accurately processed and adenylated in vitro. Alu RNAs containing 7 or 11 additional nucleotides on the 3' end were accurately processed and then adenylated. Deletion analysis showed that an 87-nucleotide-long motif comprising of the 5' and 3' ends, including stem IV of the Alu RNA, is sufficient and necessary for the 3' end processing and adenylation. A 73-nucleotide-long construct with deletion of stem IV, required for the binding of SRP 9/14-kDa proteins, was neither processed nor adenylated. The adenylated Alu RNA as well as adenylated SRP RNA were bound to the SRP 9/14-kDa heterodimer and were immunoprecipitated by specific antibodies. A significant fraction of SRP RNA in the nucleoli was found to be processed and adenylated. These data are consistent with nascent SRP and/or Alu RNAs first binding to SRP 9/14-kDa protein heterodimer, followed by the removal of extra sequence on the 3' end and then the addition of one adenylic acid residue in the nucleus, before transport into the cytoplasm.

Stepwise transplantation of an active site loop between heat-labile enterotoxins LT-II and LT-I and characterization of the obtained hybrid toxins

Members of the cholera toxin family, including Escherichia coli heat-labile enterotoxins LT-I and LT-II, catalyze the covalent modification of intracellular proteins by transfer of ADP-ribose from NAD to a specific arginine of the target protein. The ADP-ribosylating activity of these toxins is located in the A-subunit, for which LT-I and LT-II share a 63% sequence identity. The flexible loop in LT-I, ranging from residue 47 to 56, closes over the active site cleft. Previous studies have shown that point mutations in this loop have dramatic effects on the activity of LT-I. Yet, in LT-II the sequence of the equivalent loop differs at four positions from LT-I. Therefore five mutants of the active site loop were created by a stepwise replacement of the loop sequence in LT-I with virtually all the corresponding residues in LT-II. Since we discovered that LT-II had no activity versus the artificial substrate diethylamino-benzylidine-aminoguanidine (DEABAG) while LT-I does, our active site mutants most likely probe the NAD binding, not the arginine binding region of the active site. The five hybrid toxins obtained (Q49A, F52N, V53T, Q49V/F52N and Q49V/F52N/V53T) show (i) great differences in holotoxin assembly efficiency; (ii) decreased cytotoxicity in Chinese hamster ovary cells; and (iii) increased in vitro enzymatic activity compared with wild type LT-I. Specifically, the three mutants containing the F52N substitution display a greater Vmax for NAD than wild type LT-I. The enzymatic activity of the V53T mutant is significantly higher than that of wild type LT-I. Apparently this subtle variation at position 53 is beneficial, in contrast to several other substitutions at position 53 which previously had been shown to be deleterious for activity. The most striking result of this study is that the active site loop of LT-I, despite great sensitivity for point mutations, can essentially be replaced by the active site loop of LT-II, yielding an active 'hybrid enzyme' as well as 'hybrid toxin'.

Effects of haloperidol on antioxidant defense system enzymes in schizophrenia

Dysregulation of free radical metabolism as reflected by abnormal erythrocyte activities of three critical enzymes of the antioxidant defense system (AODS), i.e. superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), has been reported in schizophrenic patients. The present study examined the effects of haloperidol, a standard antipsychotic agent, on the AODS enzymes, using a within-subject, repeated-measures, on-off haloperidol treatment design. The mean drug free period was 40 days. At baseline, there were no significant differences for all three enzymes between patients and age and sex-matched normal volunteers. During the drug-free condition, SOD activity, but not GSH-Px and CAT activities, was significantly higher relative to normal control subjects. However, within-subjects both SOD and GSH-Px activities, but not CAT activity, were higher in the drug-free condition compared to the treatment condition. No significant correlation was observed between SOD activity and plasma haloperidol (or daily haloperidol dose) levels. Smoking status, as assessed by the cotinine level, was unrelated to enzyme activities. In addition, none of the major AODS enzymes showed significant differences between relapsed and clinically stable patients. These findings suggest that haloperidol may not have direct regulatory effect on AODS enzyme activities and that SOD and GSH-Px activities may change in response to other factors such as change in symptom severity.

Laparoscopic cholecystectomy in cirrhotic patients

BACKGROUND

Reported mortality for open cholecystectomy in patients with cirrhosis ranges from 10% to 80%. Laparoscopic cholecystectomy has gained acceptance in the general population and has become the procedure of choice for symptomatic cholelithiasis. We reviewed our experience with the use of laparoscopic cholecystectomy in this group.

STUDY DESIGN

We did a retrospective review of the records of 25 consecutive laparoscopic choleoystectomy procedures performed on cirrhotic patients from May 1992 to July 1996.

RESULTS

There were no mortalities in our group. All procedures were completed laparoscopically. Mean length of stay was 1.7 days (range, 1 to 8 days). Morbidity consisted of wound hematomas, pneumonia, and ascites for a rate of 32%. Only patients with Child's Class A and Class B cirrhosis were operated on.

CONCLUSIONS

Laparoscopic cholecystectomy can be performed safely in cirrhotic patients with well compensated liver function.

In vivo expression of a variant human U6 RNA from a unique, internal promoter

We previously isolated a variant of the human U6 small nuclear RNA gene (87U6) and demonstrated that transcription of this gene is controlled by a novel internal promoter. It has now been shown that two blocks of sequence within the coding region are both necessary and sufficient to direct expression of 87U6 in transcription assays performed in vitro. In addition, 87U6 is expressed in vivo and can assemble into snRNP complexes. Specific primer extension assays on total RNA from HeLa cells shows that 87U6 RNA is present in these cells. Also, microinjection of plasmid encoded 87U6 genes into Xenopus laevis oocyte nuclei results in the expression of this variant RNA. Immunoprecipitation with anti-Sm antibodies suggests that 87U6 RNA assembles into a snRNP particle with U4 snRNA. Finally, the variant snRNA is capped with the U6 specific gamma-monomethyl phosphate cap when incubated in HeLa extracts. These data suggest that 87U6 RNA may function in the splicing process, in a manner similar to the wild-type U6 RNA. The recent observations of a minor class of mRNA introns that are spliced by a distinct collection of snRNP particles suggest an important role for variant snRNAs in the splicing of transcripts with alternative splice junctions.

Sodium multiple quantum spectroscopy of articular cartilage: effects of mechanical compression

The effects of mechanical compression on the multiple quantum coherences generated from sodium ions in articular cartilage were investigated. Cartilage samples obtained from bovine patellae were studied during compression at 0.7 MPa (100 psi) for 1 hour. The double quantum filtered spectra showed marked lineshape changes in the compressed samples. Compression did not seem to influence the lineshapes of the single quantum and triple quantum filtered spectra significantly. We found that the residual quadrupolar interaction was reduced in the compressed samples. Changes in the ordering of collagen fibers may be responsible for the observed effect.

Proton T1rho-dispersion imaging of rodent brain at 1.9 T

Detection of H2(17)O with proton T1rho-dispersion imaging holds promise as a means of quantifying metabolism and blood flow with MRI. However, this technique requires a priori knowledge of the intrinsic T1rho dispersion of tissue. To investigate these properties, we implemented a T1rho imaging sequence on a 1.9-T Signa GE scanner. A series of T1rho images for different locking frequencies and locking durations were obtained from rat brain in vivo and compared with 5% (wt/vol) gelatin phantoms containing different concentrations of (17)O ranging from .037% (natural abundance) to 2.0 atom%. Results revealed that, although there is considerable T1rho-dispersion in phantoms doped with H2(17)O, the T1rho of rat brain undergoes minimal dispersion for spin-locking frequencies between .2 and 1.5 kHz. A small degree of T1rho dispersion is present below .2 kHz, which we postulate arises from natural-abundance H2(17)O. Moreover, the signal-to-noise ratios of T1rho-weighted images are significantly better than comparable T2-weighted images, allowing for improved visualization of tissue contrast. We have also demonstrated the feasibility of proton T1rho-dispersion imaging for detecting intravenous H2(17)O on a live mouse brain. The potential application of this technique to study brain perfusion is discussed.

Houseflies are an unlikely reservoir or vector for Helicobacter pylori

The route of transmission of Helicobacter pylori from individual to individual remains undefined. It has recently been reported that the domestic housefly, Musca domestica, when fed pure cultures of H. pylori, was able to harbor the organism in its midgut for up to 30 h (P. Grubel, S. Hoffman, F. K. Chong, N. A. Barstein, C. Mepani, and D. R. Cave, J. Clin. Microbiol. 35:1300-1303, 1997). Our investigation examined whether houseflies could acquire H. pylori from fresh human feces. Domestic houseflies (40 flies/group) were exposed for 24 h to feces from an H. pylori-positive volunteer, feces from an H. pylori-negative volunteer, or feces from an H. pylori-negative volunteer to which a known amount of viable H. pylori had been added. At various intervals, flies were sacrificed and the midguts were excised, homogenized, and plated in duplicate onto selective horse blood agar plates. All plates were incubated under microaerobic conditions at 37 degreesC for 14 days. Emergent colonies presumptive of H. pylori were picked and tested biochemically to confirm the identity as H. pylori. H. pylori was not recovered from houseflies fed human feces either naturally infected or artificially infected with H. pylori. These results suggest that the domestic housefly is not a vector for transmission or a reservoir for H. pylori infection.

Isolation and characterization of a new 110 kDa human nuclear RNA-binding protein (p110nrb)

RNA-protein interactions play key roles in many fundamental cellular processes such as RNA processing, RNA transport, and RNA translation. During our attempts to isolate the human U6 small nuclear RNA capping enzyme, we identified a new 110 kDa nuclear RNA-binding protein, designated p110nrb. The full-length cDNA clone for p110nrb was characterized, and it encodes a 963 amino acid polypeptide. It is a highly acidic protein (pI 5.28) and the carboxyl terminal portion contains two conserved RNP motifs. A databank search found a putative C. elegans protein that might be the p110nrb homologue. The p110nrb was overexpressed as a glutathione S-transferase fusion protein in insect Sf9 cells, purified by affinity chromatography and injected into rabbits to produce specific polyclonal antibodies. Immunofluorescent staining showed that p110nrb is distributed evenly throughout the nucleoplasm. Northern blots showed that the mRNA is expressed in all tissues examined. An in vitro RNA-binding assay showed that p110nrb bound to RNA. These data suggest that p110nrb may play a role in the metabolism of nuclear RNA.

Reduced level of plasma antioxidant uric acid in schizophrenia

There is evidence of dysregulation of the antioxidant defense system in schizophrenia. The purpose of the present study was to examine whether uric acid, a potent antioxidant, is reduced in the plasma of patients with schizophrenia. To this end, a within-subject, repeated measures, on-off-on haloperidol treatment design was utilized. Male schizophrenic patients with either a haloperidol treatment (n=47) or a drug-free condition (n=35) had significantly lower levels of plasma uric acid than the age- and sex-matched normal control subjects (n=34). Following haloperidol withdrawal, plasma uric acid levels were further reduced in schizophrenic patients (P=0.018; paired t-test, n=35). However, no relationship was found between uric acid levels and the length of the drug-free period (< 5 or > 5 weeks) or days drug free. In addition, the plasma levels of uric acid in patient groups were significantly and inversely correlated with psychosis. There was a trend for lower uric acid levels in relapsed patients relative to clinically stable patients. Smoking, which can modify plasma antioxidant capacity, was not found to have prominent effects on uric acid levels. The present finding of a significant decrease of a selective antioxidant provides additional support to the hypothesis that oxidative stress in schizophrenia may be due to a defect in the antioxidant defense system.

Reduced status of plasma total antioxidant capacity in schizophrenia

To examine whether antioxidant capacity is reduced in patients with schizophrenia, we determined plasma total antioxidant status (TAS) by quenching the absorbance of the radical cation formed by the reaction of 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) with a metmyoglobin and hydrogen peroxide. TAS serves as an index of net antioxidant activity derived from various antioxidants in plasma. Male schizophrenic patients were compared with age- and sex-matched healthy control subjects, using a within-subject, repeated measures, on-off-on haloperidol treatment design. Drug-free patients were free of all psychotropic medications for an average of 32 days. Plasma TAS was significantly lower in patients with schizophrenia than in normal controls. Plasma TAS in patients was significantly and inversely correlated with symptom severity during the drug-free condition. There were no significant differences between on and off haloperidol-treatment conditions. When patients returned to haloperidol treatment after relapse, the plasma TAS remained fairly constant and was not significantly different from the same individuals during haloperidol-stabilization or drug-free periods. These findings are indicative of an impaired antioxidant defense system, not attributable to neuroleptic treatment, and lend further support to the notion that oxidative stress may have a pathophysiological role in schizophrenia.

MRI of hyperpolarized 3He gas in human paranasal sinuses

In this study, MRI of hyperpolarized 3He gas in human paranasal sinuses is presented. Helium images were obtained at 1.5 T, using a surface coil and a 2D, fast gradient-echo sequence with a nominal constant flip angle of 12 degrees. Coronal images of 20-mm thick slices were generated and compared with proton images of the corresponding sections. The images enable visualization of the paranasal sinuses and the nasal cavity, suggesting a potential use of this method not only in identifying the anatomical configuration of these pneumatic spaces, but also in assessing sinus ventilation.

Sodium MRI of human articular cartilage in vivo

Preliminary results from in vivo sodium MRI of human patellar articular cartilage are presented. Sodium images generated of an in vitro bovine patella clearly distinguish the region of proteoglycan depletion from the region of healthy cartilage. This provides the first evidence that sodium imaging may be used to detect changes due to osteoarthritis in vivo. The process of optimizing imaging time and signal-to-noise ratio, as well as potential implications in the detection of osteoarthritic change, are discussed.

The Splendore-Hoeppli phenomenon in hepatic botryomycosis

A 68 year old diabetic man developed septicaemia and multiple liver abscesses due to Streptococcus intermedius. Liver biopsy revealed streptococcal botryomycosis which showed the Splendore-Hoeppli phenomenon. Diabetes mellitus is an example of the immunosuppressed states that have been associated with botryomycosis.

Off-resonance proton T1rho dispersion imaging of 17O-enriched tissue phantoms

Proton T1rho dispersion imaging is a recently described method for indirect detection of 17O. However, clinical implementation of this technique is hindered by the requirement for a high-amplitude spin-locking field (gammaB1 > 1 kHz) that exceeds current limitations in specific absorption rate (SAR). Here, a strategy is offered for circumventing high SAR in T1rho dispersion imaging of 17O through the use of low-amplitude off-resonance spin-locking pulses (gammaB1 < 300 Hz). Proton spin-lattice relaxation times in the off-resonance rotating frame were measured in H2(17)O-enriched tissue phantoms. On- and off-resonance T1rho dispersion imaging was implemented at 2 T using a spin-locking preparatory pulse cluster appended to a standard spin-echo sequence. On- and off-resonance dispersion images exhibited similar 17O-based image contrast. Magnetization transfer effects did not depend on 17O concentration and had no effect on image contrast. In conclusion, off-resonance proton T1rho dispersion imaging shows promise as a safe, sensitive technique for generating 17O-based T1rho contrast without exceeding SAR limitations.

Adenylation of small RNAs in human cells. Development of a cell-free system for accurate adenylation on the 3'-end of human signal recognition particle RNA

The 3'-end sequences of several human small RNAs were determined, and the results show that a fraction of human cytoplasmic 7SL, ribosomal 5S, and nuclear U2, U6, and 7SK small RNAs contain a post-transcriptionally added adenylic acid residue on their 3'-ends. Incubation of HeLa cell extract in vitro in the presence of [alpha-32P]ATP resulted in labeling of several small RNAs including ribosomal 5S and cytoplasmic 7SL as well as U2 and U6 small nuclear RNAs. Analysis of 7SL RNA labeled in this in vitro adenylation system showed that a single adenylic acid residue is added to the 3'-end. These results show that the adenylation observed in the in vitro system reflects the post-transcriptional adenylation occurring in vivo.

A comparative study of retentive strengths of zinc phosphate, polycarboxylate and glass ionomer cements with stainless steel crowns--an in vitro study

This study was conducted on 30 extracted human primary molars to assess the retentive strengths of zinc phosphate, polycarboxylate and glass ionomer cements. The teeth were embedded in resin blocks and were randomly divided into 3 groups of 10 each. The occlusal surfaces of all teeth were reduced uniformly by 1.0 to 1.5 mm. All mesial, distal undercuts were removed and sharp angles rounded. This was followed by cementing pretrimmed and precontoured stainless steel crowns on each tooth with hand pressure and storing in artificial saliva at 37 degrees C for 24 hours. Retentive strength was tested using Instron Universal Testing Machine. The load was applied starting from a zero reading and gradually increased until the cemented stainless steel crowns showed signs of movement and then the readings were recorded. It was found that retentive strengths of zinc phosphate and glass ionomer cements were statistically better (P < 0.05) when compared to the polycarboxylate cement. Negligible difference (0. 59 kg/cm2) was however observed between zinc phosphate and glass ionomer cements.

Percutaneous dilatation of biliary strictures through the afferent limb of a modified Roux-en-Y choledochojejunostomy or hepaticojejunostomy

BACKGROUND

This report is a 13-year prospective evaluation of percutaneous balloon dilatation of benign biliary strictures through the subcutaneous or subfascially positioned afferent limb of a choledocho or hepaticojejunostomy in 30 patients.

DATA SOURCE

Twenty-seven strictures developed after a common duct injury sustained at the time of cholecystectomy, two after hepatectomy reconstruction for trauma and one following a gastrectomy. Twelve injuries (40%) were recognized at operation. Of the 18 patients where the injury was unrecognized at the time of operation, 8 had not been reoperated at the time of referral, 7 had late repairs by the referring physician, and 3 had late repairs at our institution. The follow-up is 1 to 13 years.

RESULTS

There has been 1 late death and 6 patients are lost alive. The jejunal-limb was accessed 50 times with two minor and no major complications. There have been two parajejunal hernia repairs, but there have not been any reoperations for recurrent biliary strictures.

CONCLUSIONS

Benign biliary strictures can be effectively managed by repeat balloon dilatations thru the afferent limb of a choledocho or hepaticojejunostomy, thus eliminating the need for repeat surgical interventions.

Vital signs services for secure telemedicine applications

Telemedicine using teleconference provides only a part of the picture. The remote patient's electronic medical record and vital signs may often be essential for proper diagnosis and treatment. While there are commercial solutions for telemonitoring, they do not address issues such as security and interoperability leveraging the growing public communications infrastructure. On the other hand there are performance considerations due to the quality of service over available communications media that can hinder real-time operation. The objective of this research effort is to develop secure tele-monitoring facilities that enable healthcare providers to collaborate over public communication networks; to securely convey their patient's vital signs to a remote specialist; and to enable "near real-time" examination of those vital sign data. It is our belief that such applications can help overcome barriers to quality healthcare in the scattered populations of rural areas enabling telemedicine to be a part of the practice of medicine. The authors, who are developing secure telemedicine applications, describe their approach in developing secure vital signs services.

Small RNA database

The small RNA database is a compilation of all the small size RNA sequences available to date, including nuclear, nucleolar, cytoplasmic and mitochondria small RNAs from eukaryotic organisms and small RNAs from prokaryotic cells as well as viruses. Currently, approximately 600 small RNA sequences are in our database. It also gives the sources of individual RNAs and their GenBank accession numbers. The small RNA database can be accessed through the WWW (World Wide Web). Our WWW URL address is: http://mbcr.bcm.tmc. edu/smallRNA/smallrna.html . The new small RNA sequences published since our last compilation are listed in this paper (Table 1).

T1rho-relaxation in articular cartilage: effects of enzymatic degradation

Spin-lattice relaxation in the rotating frame (T1rho) dispersion spectroscopy and imaging were used to study normal and enzymatically degraded bovine articular cartilage. Normal specimens demonstrate significant T1rho "dispersion" (approximately 60 to approximately 130 ms) in the 100 Hz to 9 kHz frequency range. Proteoglycan-degraded specimens have 33% greater T1rho values than collagen-degraded or normal samples. T1rho-weighted images reveal structure not found in conventional T1- or T2-weighted images. Our results suggest that T1rho measurements are selectively sensitive to proteoglycan content. The potential of this method in distinguishing the early degenerative changes in cartilage associated with osteoarthritis is discussed.

Peripheral fibroma with calcification--a case report

A female patient aged 10 years reported with an intra oral swelling on the labial aspect of 32 & 33, appearing to originate from the marginal gingiva & interdental papilla. The swelling was pedunculated, mobile, non-tender, firm in consistency with an irregular surface. The colour of the gingiva was normal with slight ulceration. The swelling was excised & diagnosed histopathologically as peripheral cementifying/ossifying fibroma.

A simplified sequence for observing deoxymyoglobin signals in vivo: myoglobin excitation with dynamic unexcitation and saturation of water and fat (MEDUSA)

This paper describes a new, simplified pulse sequence for observing NMR signals from deoxymyoglobin in vivo. Paramagnetically shifted resonances from deoxymyoglobin can be exploited to noninvasively calculate intracellular oxygen tension in striated muscle. However, special sequences are required to observe these weak signals against the larger water and fat signals encountered in vivo. The pulse sequence described here, which is based on inversion recovery sequences, efficiently suppresses both water and fat resonances and can be implemented with short repetition rates. Moreover, it is perfectly suited for studies with surface coils, where RF inhomogeneities render other popular suppression sequences ineffective.

High resolution, short echo time sodium imaging of articular cartilage

The sodium present in articular cartilage interacts with the negatively charged proteoglycan aggregates in the matrix of the cartilage. Sodium images of short echo time may be useful for detecting changes that occur in the proteoglycan content of the cartilage. Such changes are indicative of early osteoarthritic damage, for example. Using an asymmetric short echo technique, sodium images of high resolution and signal-to-noise ratio that demonstrate anatomic features of the cartilage are presented. These images were obtained with echo times as short as 1 msec, at an in-plane resolution of 39 microns by 117 microns and signal-to-noise ratios of up to 40:1.

Expression of MAGE genes in ocular melanoma during progression from primary to metastatic disease

Primary melanomas that form within the eye have a unique pattern of disease progression as compared with melanomas that form within the skin. A high percentage of patients (approximately 50%) develop metastatic tumors that occur predominately in the liver. An unusual characteristic of ocular melanomas is the prolonged disease-free interval that extends for many years between the development of primary and metastatic tumors. It is estimated that the shortest interval between dissemination of tumor cells from the eye and the appearance of clinically detectable metastases is 6 years. A recent report indicated that fresh uveal melanoma tissue and metastatic tumor biopsies failed to express melanoma antigen gene (MAGE)-1, MAGE-2, or MAGE-3. In the present study, we examined the expression of MAGE genes on fresh and cultured tumor cells obtained from an ocular melanoma patient during different stages of progressive disease. MAGE gene expression was determined by reverse transcription-polymerase chain reaction using MAGE-1, MAGE-2 and MAGE-3 specific primers. Our results demonstrate that primary ocular tumor tissue and cultured tumor cells both express significant levels of MAGE-1, 2, and 3 at the time of enucleation. A high percentage of tumor cells within the primary tumor appear to express MAGE as demonstrated by consistent MAGE expression in 16 tumor cell clones. Metastatic liver tumors that developed 3 years after enucleation and 18 years after the initial formation of the primary tumor also expressed high levels of MAGE-1, -2, and -3. MAGE was expressed on fresh tumor tissue from a single biopsy and cultured tumor cells obtained from three of four different metastatic tumor nodules. When the MAGE-negative metastatic tumor cells were treated with the demethylating agent 5-Aza-2-Deoxycytidine (5-Aza-dC), transcription of MAGE-1 was restored, indicating the MAGE genes were not deleted. Our results demonstrate that in some patients, MAGE genes are expressed on primary and metastatic ocular melanomas.

Formation of 2',3'-cyclic phosphates at the 3' end of human U6 small nuclear RNA in vitro. Identification of 2',3'-cyclic phosphates at the 3' ends of human signal recognition particle and mitochondrial RNA processing RNAs

Approximately 90% of human U6 small nuclear RNA (snRNA) contains uridine cyclic phosphate (U>p) at its 3'-end (Lund, E., and Dahlberg, J. E. (1992) Science 255, 327-330). We studied the formation of U>p at the 3' end of human U6 snRNA using an in vitro system where uridylic acid residues are added from UTP precursor and U>p is formed. Analysis of U6 snRNAs with varying number of uridylic acid residues showed that each of these species contains U>p where the phosphate originated from alpha-phosphate of UTP precursor. The cyclic phosphate formation occurred on U6 snRNA in extracts where essential spliceosomal snRNAs were specifically degraded, thereby indicating that U>p formation is not coupled to pre-mRNA splicing. A subpopulation of human signal recognition particle and mitochondrial RNA processing RNAs isolated from HeLa cells also contained cyclic phosphates at their 3' ends. These data suggest that U>p in U6 snRNA is unlikely to be related to its participation in splicing of pre-mRNAs. It appears that cyclic phosphate is an intermediate product in the metabolism of these small RNAs.

Triple quantum sodium imaging of articular cartilage

Triple quantum (TQ) sodium imaging of bovine articular cartilage is presented. True triple quantum imaging sequence was modified to incorporate asymmetric echo acquisition. Triple quantum signal expression in the presence of residual quadrupolar interaction is presented. The filtering capability of the sequence is first demonstrated on an agarose phantom. Both single and triple quantum images of articular cartilage are compared. The TQ image shows non-zero signal intensity solely from cartilage, indicating complete suppression of signals from bone marrow and saline. The advantages of TQ imaging of articular cartilage, its feasibility in in vivo situations and further improvements in SNR are described.

Collaboration Technology for Rural Health-care

Health-care is a collaborative endeavor involving a number of individuals and organizations with diverse perspectives. Computer-supported collaboration technologies have great potential to enable health-care providers to improve the quality of care provided to their patients. Such technologies have the potential to overcome barriers to quality health-care in the small, scattered populations of rural areas. Rapid changes in technology are making it more and more possible for collaborative telemedicine to be a part of the practice of medicine. The World Wide Web has amply demonstrated that the globe has shrunk and information from afar is a mere mouse click away. However, the ease with which information is accessed along with the potential disclosure and misuse of personal information has raised serious concerns about the ability to restrict such information to legitimate accesses by duly authorized health-care providers. The authors present their experience in developing a health-care collaboration facility, ARTEMIS, which enabled Web-based access to electronic medical records, and provide a vision of their experiment to provide secure telemedicine for rural health-care practitioners.

In vivo sodium multiple quantum spectroscopy of human articular cartilage

The authors report, for the first time, sodium properties of human articular cartilage in vivo using sodium multiple-quantum-filtered methods with a surface coil. A flip angle-independent, phase-cycled pulse sequence was used to obtain triple-quantum-filtered spectra as a function of preparation time. Biexponential relaxation rates were calculated by fitting the triple-quantum-filtered spectral amplitudes to a theoretical expression. Theoretical analysis of the flip angle dependence of even rank two-quantum coherence (T2[2]), odd rank two-quantum coherence (T2[3]), and triple-quantum coherence are presented and verified against experimental results on a cartilage specimen. Sodium multiple-quantum-filtered spectral lineshapes obtained in vivo correlate well with those observed on in vitro specimens. Relaxation rates obtained from asymptomatic volunteers were found to be: T(2rise) = 1.0 + 0.12 ms, T(2decay) = 12.0 +/- 0.75 ms (mean +/- SD). The diagnostic potential of this method in detecting early changes in articular cartilage is described.

Point mutations in the 23S rRNA gene of Helicobacter pylori associated with different levels of clarithromycin resistance

Fifty-four of 59 (91.5%) clarithromycin-resistant isolates of Helicobacter pylori from different patients possessed either the A2143G (formerly A2058G) or the A2144G (formerly A2059G) mutation in the gene encoding 23S rRNA. The A2143G mutation was significantly more likely to occur in isolates with MICs exceeding 64 mg/L (65% versus 30% with the A2144G mutation; P = 0.01). The majority (26 of 31; 83.9%) of isolates with the A2143G mutation had MICs exceeding 64 mg/L. Peptic ulcer disease recurred in a substantial proportion of patients infected with H. pylori strains containing either the A2143G or the A2144G mutation.