A phase 2 trial of ponatinib in Philadelphia chromosome-positive leukemias

BACKGROUND

Ponatinib is a potent oral tyrosine kinase inhibitor of unmutated and mutated BCR-ABL, including BCR-ABL with the tyrosine kinase inhibitor-refractory threonine-to-isoleucine mutation at position 315 (T315I). We conducted a phase 2 trial of ponatinib in patients with chronic myeloid leukemia (CML) or Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph-positive ALL).

METHODS

We enrolled 449 heavily pretreated patients who had CML or Ph-positive ALL with resistance to or unacceptable side effects from dasatinib or nilotinib or who had the BCR-ABL T315I mutation. Ponatinib was administered at an initial dose of 45 mg once daily. The median follow-up was 15 months.

RESULTS

Among 267 patients with chronic-phase CML, 56% had a major cytogenetic response (51% of patients with resistance to or unacceptable side effects from dasatinib or nilotinib and 70% of patients with the T315I mutation), 46% had a complete cytogenetic response (40% and 66% in the two subgroups, respectively), and 34% had a major molecular response (27% and 56% in the two subgroups, respectively). Responses were observed regardless of the baseline BCR-ABL kinase domain mutation status and were durable; the estimated rate of a sustained major cytogenetic response of at least 12 months was 91%. No single BCR-ABL mutation conferring resistance to ponatinib was detected. Among 83 patients with accelerated-phase CML, 55% had a major hematologic response and 39% had a major cytogenetic response. Among 62 patients with blast-phase CML, 31% had a major hematologic response and 23% had a major cytogenetic response. Among 32 patients with Ph-positive ALL, 41% had a major hematologic response and 47% had a major cytogenetic response. Common adverse events were thrombocytopenia (in 37% of patients), rash (in 34%), dry skin (in 32%), and abdominal pain (in 22%). Serious arterial thrombotic events were observed in 9% of patients; these events were considered to be treatment-related in 3%. A total of 12% of patients discontinued treatment because of an adverse event.

CONCLUSIONS

Ponatinib had significant antileukemic activity across categories of disease stage and mutation status. (Funded by Ariad Pharmaceuticals and others; PACE ClinicalTrials.gov number, NCT01207440 .).

The outbreak of West Nile virus infection in the New York City area in 1999

BACKGROUND

In late August 1999, an unusual cluster of cases of meningoencephalitis associated with muscle weakness was reported to the New York City Department of Health. The initial epidemiologic and environmental investigations suggested an arboviral cause.

METHODS

Active surveillance was implemented to identify patients hospitalized with viral encephalitis and meningitis. Cerebrospinal fluid, serum, and tissue specimens from patients with suspected cases underwent serologic and viral testing for evidence of arboviral infection.

RESULTS

Outbreak surveillance identified 59 patients who were hospitalized with West Nile virus infection in the New York City area during August and September of 1999. The median age of these patients was 71 years (range, 5 to 95). The overall attack rate of clinical West Nile virus infection was at least 6.5 cases per million population, and it increased sharply with age. Most of the patients (63 percent) had clinical signs of encephalitis; seven patients died (12 percent). Muscle weakness was documented in 27 percent of the patients and flaccid paralysis in 10 percent; in all of the latter, nerve conduction studies indicated an axonal polyneuropathy in 14 percent. An age of 75 years or older was an independent risk factor for death (relative risk adjusted for the presence or absence of diabetes mellitus, 8.5; 95 percent confidence interval, 1.2 to 59.1), as was the presence of diabetes mellitus (age-adjusted relative risk, 5.1; 95 percent confidence interval, 1.5 to 17.3).

CONCLUSIONS

This outbreak of West Nile meningoencephalitis in the New York City metropolitan area represents the first time this virus has been detected in the Western Hemisphere. Given the subsequent rapid spread of the virus, physicians along the eastern seaboard of the United States should consider West Nile virus infection in the differential diagnosis of encephalitis and viral meningitis during the summer months, especially in older patients and in those with muscle weakness.

Suppression by diets rich in fish oil of very low density lipoprotein production in man

The highly polyunsaturated fatty acids in fish oils lower the plasma triglyceride concentration. We have studied the effect of a diet rich in fish oil on the rate of production of the triglyceride-transporting very low density lipoprotein (VLDL). Seven subjects, five normal and two with hypertriglyceridemia received up to 30% of daily energy needs from a fish oil preparation that was rich in eicosapentaenoic acid and docosahexaenoic acid, omega-3 fatty acids with five and six double bonds, respectively. Compared with a diet similarly enriched with safflower oil (in which the predominant fatty acid is the omega-6 linoleic acid, with two double bonds), the fish oil diet lowered VLDL lipids and B apoprotein concentrations profoundly. High density lipoprotein lipids and A1 apoprotein were also lowered, but the effect on low density lipoprotein (LDL) concentration was inconsistent. The daily production or flux of VLDL apoprotein B, calculated from reinjected autologous 125I-labeled lipoprotein, was substantially less in six subjects studied after 3 wk of fish oil, compared with after safflower oil. This effect on flux was more consistent than that on the irreversible fractional removal rate, which was increased in the four normolipidemic but inconsistent in the hypertriglyceridemic subjects. This suggests that fish oil reduced primarily the production of VLDL. The daily production of VLDL triglyceride, calculated from the kinetics of the triglyceride specific radioactivity-time curves after [3H]glycerol was injected, also showed very substantial reductions in five subjects studied. The marked suppression in VLDL apoprotein B and VLDL triglyceride formation was found not to be due to diminished plasma total free fatty acid or plasma eicosapentaenoic flux, calculated during constant infusions of [14C]eicosapentaenoic acid and [3H]oleic acid in four subjects. In two subjects there was presumptive evidence for substantial independent influx of LDL during the fish oil diet, based on the precursor-product relationship between the intermediate density lipoprotein and LDL apoprotein B specific radioactivity-time curves.

The Biomolecular Interaction Network Database and related tools 2005 update

The Biomolecular Interaction Network Database (BIND) (http://bind.ca) archives biomolecular interaction, reaction, complex and pathway information. Our aim is to curate the details about molecular interactions that arise from published experimental research and to provide this information, as well as tools to enable data analysis, freely to researchers worldwide. BIND data are curated into a comprehensive machine-readable archive of computable information and provides users with methods to discover interactions and molecular mechanisms. BIND has worked to develop new methods for visualization that amplify the underlying annotation of genes and proteins to facilitate the study of molecular interaction networks. BIND has maintained an open database policy since its inception in 1999. Data growth has proceeded at a tremendous rate, approaching over 100 000 records. New services provided include a new BIND Query and Submission interface, a Standard Object Access Protocol service and the Small Molecule Interaction Database (http://smid.blueprint.org) that allows users to determine probable small molecule binding sites of new sequences and examine conserved binding residues.

Type C retrovirus released from porcine primary peripheral blood mononuclear cells infects human cells

As part of the evaluation of porcine cells, tissues, and organs intended for transplantation into humans, we investigated the conditions required to induce expression and release of porcine endogenous retrovirus (PoEV) from primary cells. Pigs contain endogenous retroviral sequences encoding infectious retrovirus, yet little is known about the conditions required to activate the expression and release of PoEV from primary cells. We show here that mitogenic activation of peripheral blood mononuclear cells (PBMC) isolated from the National Institutes of Health (NIH) miniature pig and the Yucatan pig resulted in the activation and release of an infectious type C retrovirus. Coculture of activated porcine PBMC with pig or human cell lines resulted in the transfer and expression of PoEV-specific sequences and the establishment of a productive infection. Sequence comparison of portions of the PoEV pol gene expressed in pig cell lines productively infected with virus derived from NIH miniature pig and Yucatan pig PBMC revealed marked similarity, suggesting that one or a few loci may be capable of being activated to yield an infectious virus. These findings demonstrate that the presence of endogenous viruses in source animals needs to be carefully considered when the infectious disease potential of xenotransplantation is being assessed.

Acoustic characteristics of English fricatives

This study constitutes a large-scale comparative analysis of acoustic cues for classification of place of articulation in fricatives. To date, no single metric has been found to classify fricative place of articulation with a high degree of accuracy. This study presents spectral, amplitudinal, and temporal measurements that involve both static properties (spectral peak location, spectral moments, noise duration, normalized amplitude, and F2 onset frequency) and dynamic properties (relative amplitude and locus equations). While all cues (except locus equations) consistently serve to distinguish sibilant from nonsibilant fricatives, the present results indicate that spectral peak location, spectral moments, and both normalized and relative amplitude serve to distinguish all four places of fricative articulation. These findings suggest that these static and dynamic acoustic properties can provide robust and unique information about all four places of articulation, despite variation in speaker, vowel context, and voicing.

Randomized study of brachytherapy in the initial management of patients with malignant astrocytoma

PURPOSE

A randomized study was undertaken to assess the role of brachytherapy as a boost to external beam radiation therapy in the initial management of patients with malignant astrocytomas.

METHODS AND MATERIALS

Inclusion criteria included the following: biopsy-proven supratentorial malignant astrocytoma of brain < or =6 cm in size, not crossing midline or involving corpus callosum, age 18-70, Karnofsky Performance Status (KPS) > or =70. Patients were randomized to external radiation therapy only delivering 50 Gray (Gy) in 25 fractions over 5 weeks or external radiation therapy plus a temporary stereotactic iodine-125 implants delivering a minimum peripheral tumor dose of 60 Gy. Patients were stratified to age < or =50 or >50, and KPS > or =90 or < or =80.

RESULTS

There were 140 patients randomized between 1986 and 1996, 71 to the implant arm and 69 to external irradiation only. Pathologically 125 patients had necrosis noted in their tumor specimen. Factors associated with improved survival in univariate analysis were age < or =50, KPS > or =90, chemotherapy at recurrence, and reoperation at the original tumor site. The Cox proportional hazards model revealed the following significant factors: treatment at recurrence (chemotherapy or reoperation) with a relative risk (RR) of 0.6 (p = 0.004) and KPS > or =90 with a RR 0.6 (p = 0.007). Randomization to the implant arm was associated with a RR of 0.7 (p = 0.07). Median survival for patients randomized to brachytherapy or not were 13.8 vs. 13.2 months, respectively, p = 0.49.

CONCLUSIONS

We conclude that stereotactic radiation implants have not demonstrated a statistically significant improvement in survival in the initial management of patients with malignant astrocytoma.

Drug-drug and drug-disease interactions in the ED: analysis of a high-risk population

A study was undertaken to determine the potential for adverse drug interactions (ADIs) and drug-disease interactions (DDIs) in a high-risk population of emergency department (ED) patients and to characterize drug-drug and drug-disease interactions in terms of percentage of patients at risk from existing drug regimens, percentage of patients at risk from ED treatment, relation between number of drugs and potential for interactions, types of drugs and diseases posing greatest potential for interaction, and the differences in a general versus community hospital population with respect to these parameters. Records of 205 consecutive patients, 111 from a general hospital teaching facility ED (Facility 1) and 94 from a community hospital ED (Facility 2) were retrospectively reviewed. The records of all patients receiving three or more medications and all patients older than 50 years of age receiving two or more medications were analyzed by two computer programs for the presence of potential drug-drug and drug-disease interactions. A total of 226 potential ADIs were found in 89 patients (47%), with 50% of ADIs being related to ED treatment. A total of 94 potential DDIs were found in 44 patients (21%), with 34% of DDIs being related to ED treatment. The risk of an ADI rose from 13% for patients taking 2 medications to 82% for patients taking 7 or more medications. Eleven medications and four disease categories were identified as having particular potential for interactions. No significant differences were found between the general and the community hospital populations in these respects. ED patients taking three or more medications and patients older than 50 years of age taking two or more medications are at substantial risk for adverse drug-drug and drug-disease interactions. The risk is increased in patients taking particular drugs or having particular disease states.

Antibodies to metabotropic glutamate receptor 5 in the Ophelia syndrome

OBJECTIVE

To report the metabotropic glutamate receptor 5 (mGluR5) as the autoantigen of antibodies from 2 patients with Hodgkin lymphoma (HL) and limbic encephalopathy (Ophelia syndrome).

METHODS

Immunohistochemistry with brain tissue and cultures of rat hippocampal neurons were used to demonstrate antibodies. Immunoprecipitation, mass spectrometry, and mGluR5-null mice served to identify the antigen. HEK293 cells transfected with mGluR5 or mGluR1 were used to determine immunologic crossreactivity.

RESULTS

Both patients developed symptoms consistent with limbic encephalopathy; one had MRI findings typical of this disorder and the other had more extensive radiologic involvement, including parietal and occipital cortex. Patients' sera had antibodies that predominantly reacted with the neuropil of hippocampus and cell surface of live hippocampal neurons. Immunoprecipitation from cultured neurons and mass spectrometry demonstrated that the antigen was mGluR5, a receptor involved in processes of learning and memory. The reactivity of patients' sera was abrogated in brain of mGluR5-null mice, further confirming the antibody specificity. Studies with a large number of controls including 2 patients with cerebellar ataxia and mGluR1 antibodies showed that mGluR5 was only identified by sera of the 2 patients with the Ophelia syndrome, and that despite the homology of this receptor with mGluR1 each autoantigen was specific for a distinct syndrome.

CONCLUSIONS

Antibodies to mGluR5 should be considered in patients with symptoms of limbic encephalitis and HL (Ophelia syndrome). Recognition of this disorder is important because it can affect young individuals and is reversible.

Adherence to statin treatment and readmission of patients after myocardial infarction: a six year follow up study

OBJECTIVE

To investigate patients' adherence to statin treatment prescribed following their first myocardial infarction (MI) and to estimate the effect of adherence to statins on recurrence of MI and all cause mortality.

DESIGN

Cohort study using a record linkage database.

SETTING

Tayside, Scotland, UK.

PATIENTS

Patients who experienced their first MI between January 1990 and November 1995.

MAIN OUTCOME MEASURES

Percentage of statin use and adherence to statins by patients after an MI and the relative risk of hospitalisation for recurrent MI. The effect of adherence on all cause mortality was also examined. The covariates used were age, sex, socioeconomic deprivation, serum cholesterol concentration, diabetes mellitus, cardiovascular drug use, and other hospitalisations.

RESULTS

Of 5590 patients who experienced an incident MI, 717 (12.8%) experienced at least one further MI. Only 7.7% of patients used statins after an MI during the study period. Compared with those not taking statins, those who had 80% or better adherence to statin treatment had an adjusted relative risk of recurrent MI of 0.19 (95% confidence interval (CI) 0.08 to 0.47) and all cause mortality of 0.47 (95% CI 0.22 to 0.99). There was no significant reduction in either end point for those who were less than 80% adherent to statins.

CONCLUSIONS

Despite the infrequent use of statin during the study period, good adherence to statin treatment was associated with lower risk of recurrent MI.

Mechanical function of dystrophin in muscle cells

We have directly measured the contribution of dystrophin to the cortical stiffness of living muscle cells and have demonstrated that lack of dystrophin causes a substantial reduction in stiffness. The inferred molecular structure of dystrophin, its preferential localization underlying the cell surface, and the apparent fragility of muscle cells which lack this protein suggest that dystrophin stabilizes the sarcolemma and protects the myofiber from disruption during contraction. Lacking dystrophin, the muscle cells of persons with Duchenne muscular dystrophy (DMD) are abnormally vulnerable. These facts suggest that muscle cells with dystrophin should be stiffer than similar cells which lack this protein. We have tested this hypothesis by measuring the local stiffness of the membrane skeleton of myotubes cultured from mdx mice and normal controls. Like humans with DMD mdx mice lack dystrophin due to an x-linked mutation and provide a good model for the human disease. Deformability was measured as the resistance to indentation of a small area of the cell surface (to a depth of 1 micron) by a glass probe 1 micron in radius. The stiffness of the membrane skeleton was evaluated as the increment of force (mdyne) per micron of indentation. Normal myotubes with an average stiffness value of 1.23 +/- 0.04 (SE) mdyne/micron were about fourfold stiffer than myotubes cultured from mdx mice (0.34 +/- 0.014 mdyne/micron). We verified by immunofluorescence that both normal and mdx myotubes, which were at a similar developmental stage, expressed sarcomeric myosin, and that dystrophin was detected, diffusely distributed, only in normal, not in mdx myotubes. These results confirm that dystrophin and its associated proteins can reinforce the myotube membrane skeleton by increasing its stiffness and that dystrophin function and, therefore, the efficiency of therapeutic restoration of dystrophin can be assayed through its mechanical effects on muscle cells.

13C NMR of Nephila clavipes major ampullate silk gland

The major ampullate glands of the spider Nephila clavipes contain approximately 0.2 microliter each of a highly concentrated (approximately 50%) solution of silk fibroin. Therefore, the reservoir of silk in these glands presents an ideal opportunity to observe prefolded conformations of a protein in its native state. To this end, the structure and conformation of major ampullate gland silk fibroin within the glands of the spider N. clavipes were examined by 13C NMR spectroscopy. These results were compared to those from silk protein first drawn from the spinneret and then denatured. The 13C NMR chemical shifts, along with infrared and circular dichroism data, suggest that the silk fibroin in the glands exists in dynamically averaged helical conformations. Furthermore, there is no evidence of proline residues in U-(13)C-D-glucose-labeled silk. This transient prefolded "molten fibril" state may correspond to the silk I form found in Bombyx mori silk. There is no evidence of the final beta-sheet structure in the ampullate gland silk fibroin before final silk processing. However, the conformation of silk in the glands appears to be in a highly metastable state, as plasticization with water produces the beta-sheet structure. Therefore, the ducts connecting the ampullate glands to the spinnerets play a larger role in silk processing than previously thought.

Extended analysis of the in vitro tropism of porcine endogenous retrovirus

We previously reported that mitogenic activation of porcine peripheral blood mononuclear cells resulted in production of porcine endogenous retrovirus(es) (PERV[s]) capable of productively infecting human cells (C. Wilson et al., J. Virol. 72:3082-3087, 1998). We now extend that analysis to show that additional passage of isolated virus, named here PERV-NIH, through a human cell line yielded a viral population with a higher titer of infectious virus on human cells than the initial isolate. We show that in a single additional passage on a human cell line, the increase in infectivity for human cells is accounted for by selection against variants carrying pig-tropic envelope sequences (PERV-C) as well as by enrichment for replication-competent genomes. Sequence analysis of the envelope cDNA present in virions demonstrated that the envelope sequence of PERV-NIH is related to but distinct from previously reported PERV envelopes. The in vitro host range of PERV was studied in human primary cells and cell lines, as well as in cell lines from nonhuman primate and other species. This analysis reveals three patterns of susceptibility to infection among these host cells: (i) cells are resistant to infection in our assay; (ii) cells are infected by virus, as viral RNA is detected in the supernatant by reverse transcription-PCR, but the cells are not permissive to productive replication and spread; and (iii) cells are permissive to low-level productive replication. Certain cell lines were permissive for efficient productive infection and spread. These results may prove useful in designing appropriate animal models to assess the in vivo infectivity properties of PERV.

Linking the Rb and polycomb pathways

Polycomb group (PcG) proteins associate to form complexes that repress Hox genes, thereby imposing the patterning of Hox expression required for development. However, these proteins have a second Hox-independent role in regulating cell proliferation. Our results suggest that association between Rb and PcG proteins forms a repressor complex that blocks entry of cells into mitosis. Also, we provide evidence that Rb colocalizes with nuclear PcG complexes and is important for association of PcG complexes with nuclear targets. The Rb-PcG complex may provide a means to link cell cycle arrest to differentiation events leading to embryonic pattern formation.

Glioblastoma multiforme occurring in a patient treated with gamma knife surgery

✓ Stereotactic radiosurgery is being increasingly advocated as the primary modality for treatment of vestibular schwannomas (VS). This modality has been shown to arrest tumor growth, with few associated short-term morbidities, and with possibly better hearing and facial nerve preservation rates than microsurgery. Radiation-induced oncogenesis has long been recognized, although stereotactic radiosurgery de novo induction of a secondary tumor has never been clearly described. The authors report on a patient with a VS who did not have neurofibromatosis Type 2 and who underwent gamma knife surgery (GKS). This patient required microsurgical removal of the VS within 8 months because of development of a tumor cyst with associated brainstem compression and progressive hydrocephalus. The operation resulted in clinical stabilization and freedom from tumor recurrence.

Seven and a half years after undergoing GKS, the patient presented with symptoms of raised intracranial pressure. Magnetic resonance imaging demonstrated a new ring-enhancing lesion in the inferior temporal lobe adjacent to the area of radiosurgery, which on craniotomy was confirmed to be a glioblastoma multiforme (GBM). Despite additional conventional external-beam radiation to the temporal lobe, the GBM has progressed. Whereas this first reported case of a GBM within the scatter field of GKS does not conclusively prove a direct causal link, it does fulfill all of Cahan's criteria for radiation-induced neoplasia, and demands increased vigilance for the potential long-term complications of stereotactic radiosurgery, and reporting of any similar cases.

Intrinsic efficacy of antipsychotics at human D2, D3, and D4 dopamine receptors: identification of the clozapine metabolite N-desmethylclozapine as a D2/D3 partial agonist

Drugs that antagonize D2-like receptors are effective antipsychotics, but the debilitating movement disorder side effects associated with these drugs cannot be dissociated from dopamine receptor blockade. The "atypical" antipsychotics have a lower propensity to cause extrapyramidal symptoms (EPS), but the molecular basis for this is not fully understood nor is the impact of inverse agonism upon their clinical properties. Using a cell-based functional assay, we demonstrate that overexpression of Galphao induces constitutive activity in the human D2-like receptors (D2, D3, and D4). A large collection of typical and atypical antipsychotics was profiled for activity at these receptors. Virtually all were D2 and D3 inverse agonists, whereas none was D4 inverse agonist, although many were potent D4 antagonists. The inverse agonist activity of haloperidol at D2 and D3 receptors could be reversed by mesoridazine demonstrating that there were significant differences in the degrees of inverse agonism among the compounds tested. Aripiprazole and the principle active metabolite of clozapine NDMC [8-chloro-11-(1-piperazinyl)-5H-dibenzo [b,e] [1,4] diazepine] were identified as partial agonists at D2 and D3 receptors, although clozapine itself was an inverse agonist at these receptors. NDMC-induced functional responses could be reversed by clozapine. It is proposed that the low incidence of EPS associated with clozapine and aripiprazole used may be due, in part, to these partial agonist properties of NDMC and aripiprazole and that bypassing clozapine blockade through direct administration of NDMC to patients may provide superior antipsychotic efficacy.

Resveratrol, an extract of red wine, inhibits lipopolysaccharide induced airway neutrophilia and inflammatory mediators through an NF-kappaB-independent mechanism

Consumption of a naturally occurring polyphenol, resveratrol, in particular through drinking moderate amounts of red wine, has been suggested to be beneficial to health. A plethora of in vitro studies published demonstrate various anti-inflammatory actions of resveratrol. The aim of this research was to determine whether any of these anti-inflammatory effects translate in vivo in a rodent model of LPS induced airway inflammation. Resveratrol reduced lung tissue neutrophilia to a similar magnitude as that achieved by treatment with budesonide. This was associated with a reduction in pro-inflammatory cytokines and prostanoid levels. Interestingly, the reduction did not appear to be due to an impact on NF-kappaB activation or the expression of the respective genes as suggested by various in vitro publications. These results suggest that resveratrol may possess anti-inflammatory properties via a novel mechanism. Elucidation of this mechanism may lead to potential new therapies for the treatment of chronic inflammation.

Killer whale (Orcinus orca) hearing: auditory brainstem response and behavioral audiograms

Killer whale (Orcinus orca) audiograms were measured using behavioral responses and auditory evoked potentials (AEPs) from two trained adult females. The mean auditory brainstem response (ABR) audiogram to tones between 1 and 100 kHz was 12 dB (re 1 mu Pa) less sensitive than behavioral audiograms from the same individuals (+/- 8 dB). The ABR and behavioral audiogram curves had shapes that were generally consistent and had the best threshold agreement (5 dB) in the most sensitive range 18-42 kHz, and the least (22 dB) at higher frequencies 60-100 kHz. The most sensitive frequency in the mean Orcinus audiogram was 20 kHz (36 dB), a frequency lower than many other odontocetes, but one that matches peak spectral energy reported for wild killer whale echolocation clicks. A previously reported audiogram of a male Orcinus had greatest sensitivity in this range (15 kHz, approximately 35 dB). Both whales reliably responded to 100-kHz tones (95 dB), and one whale to a 120-kHz tone, a variation from an earlier reported high-frequency limit of 32 kHz for a male Orcinus. Despite smaller amplitude ABRs than smaller delphinids, the results demonstrated that ABR audiometry can provide a useful suprathreshold estimate of hearing range in toothed whales.

A randomized controlled trial of surgery vs steroid injection for carpal tunnel syndrome

BACKGROUND

Decompressive surgery and steroid injection are widely used forms of treatment for carpal tunnel syndrome (CTS) but there is no consensus on their effectiveness in comparison to each other. The authors evaluated the efficacy of surgery vs steroid injection in relieving symptoms in patients with CTS.

METHODS

The authors conducted a randomized, single blind, controlled trial. Fifty patients with electrophysiologically confirmed idiopathic CTS were randomized and assigned to open carpal tunnel release (25 patients) or to a single injection of steroid (25 patients). Patients were followed up at 6 and 20 weeks. The primary outcome was symptom relief in terms of the Global Symptom Score (GSS), which rates symptoms on a scale of 0 (no symptoms) to 50 (most severe). Nerve conduction studies and grip strength measurements were used as secondary outcome assessments.

RESULTS

At 20 weeks after randomization, patients who underwent surgery had greater symptomatic improvement than those who were injected. The mean improvement in GSS after 20 weeks was 24.2 (SD 11.0) in the surgery group vs 8.7 (SD 13.0) in the injection group (p < 0.001); surgical decompression also resulted in greater improvement in median nerve distal motor latencies and sensory nerve conduction velocity. Mean grip strength in the surgical group was reduced by 1.7 kg (SD 5.1) compared with a gain of 2.4 kg (SD 5.5) in the injection group.

CONCLUSION

Compared with steroid injection, open carpal tunnel release resulted in better symptomatic and neurophysiologic outcome but not grip strength in patients with idiopathic carpal tunnel syndrome over a 20-week period.

Nucleotide sequence of the gyrA gene and characterization of ciprofloxacin-resistant mutants of Helicobacter pylori

PCR was used to amplify a 238-bp region from Helicobacter pylori which corresponded to the quinolone resistance-determining region in Escherichia coli. The gyrA gene of H. pylori was cloned and sequenced. An open reading frame of 2,478 nucleotides coded for a polypeptide of 826 amino acids with a calculated molecular mass of 92,508 Da. The amino acid sequence showed an overall 52% identity with other bacterial gyrA genes but was most closely related to the gyrA subunit of Campylobacter jejuni (76.5% identity). Sequencing of the amplification product from ciprofloxacin-resistant mutants of H. pylori revealed four classes of mutations with substitutions at amino acid 87 (Asn-->Lys), amino acid 88 (Ala-->Val), and amino acid 91 (Asp-->Gly, -->Asn, or -->Tyr) and a double substitution at amino acids 91 and 97 (Ala-->Val). Ciprofloxacin-susceptible strains of H. pylori could be transformed to ciprofloxacin resistance by using the amplified fragment from resistant strains as donor DNA. Of the 11 ciprofloxacin-resistant mutants examined, only one did not have an alteration within the quinolone resistance-determining region, suggesting that, in H. pylori, resistance to quinolones is primarily a result of alterations in gyrA.

Construction of stabilized proteins by combinatorial consensus mutagenesis

We constructed stabilized variants of beta-lactamase (BLA) from Enterobacter cloacae by combinatorial recruitment of consensus mutations. By aligning the sequences of 38 BLA homologs, we identified 29 positions where the E.cloacae gene differs from the consensus sequence of lactamases and constructed combinatorial libraries using mixtures of mutagenic oligonucleotides encompassing all 29 positions. Screening of 90 random isolates from these libraries identified 15 variants with significantly increased thermostability. The stability of these isolates suggest that all tested mutations make additive contributions to protein stability. A statistical analysis of sequence and stability data identified 11 mutations that made stabilizing contributions and eight mutations that destabilized the protein. A second-generation library recombining these 11 stabilizing mutations led to the identification of BLA variants that showed further stabilization. The most stable variant had a mid-point of thermal denaturation (Tm) that was 9.1 degrees C higher than the starting molecule and contained eight consensus mutations. Incubation of three stabilized BLA variants with several proteases showed that all tested isolates have significantly increased resistance to proteolysis. Our data demonstrate that combinatorial consensus mutagenesis (CCM) allows the rapid generation of protein variants with improved thermal and proteolytic stability.

Common effects of touch and vision on postural parameters

Subjects stood upright with the index finger of the right hand either touching a nearby surface gently or not touching it at all and with the eyes either open or closed. Trajectories of the center of pressure (COP) were analyzed as fractional Brownian motion. The extracted parameters were the effective diffusion (D) coefficients and Hurst (H) exponents for short-term time intervals (corresponding to positively correlated random walks) and long-term time intervals (corresponding to negatively correlated random walks). Gentle tactile contact reduced the effective stochastic activity measured by D to the same extent as the availability of vision. Further, touch interacted with time interval in the same way as vision, with the correlated activity closer to H = 0.5 at both time scales when the finger contacted the nearby surface. The results corroborate and extend major features of recent investigations of haptic influences on posture and recent analyses of vision's influence on the fractional Brownian motions of the COP. Discussion focused on (a) the equivalence of expropriospecific information (about the body's orientation to the environment) registered haptically and visually and (b) the possibility that postural sway may reflect exploratory motions in the short term (obtaining information about the postural system) and performatory motions in the long term (using this information).

Visual and circadian responses to light in aged retinally degenerate mice

The progression of photoreceptor degeneration in retinally degenerate (rd) mice commences early in postnatal development resulting in the complete loss of rods by 60-70 days of age followed by the more protracted loss of cones. We have previously shown that rd mice 80 days of age are capable of phase shifting their circadian locomotor rhythms in response to brief pulses of light and these animals show the same sensitivity as wild-type (+/+) controls. If surviving cones mediate these circadian responses, then one would expect the sensitivity of the circadian system in rd mice to decline with age and parallel the loss of cones. We demonstrate that aging rd mice (80-767 days of age) remain capable of photically regulating circadian locomotor rhythms in a manner indistinguishable from +/+ mice. Circadian responses to light do not parallel cone cell degeneration in rd mice. In contrast to the circadian responses to light, old (> 210 days of age) rd mice show no visually-evoked behavioral or electroretinogram (ERG) responses.

Reduced triglyceride formation from long-chain polyenoic fatty acids in rat hepatocytes

The mechanism for the marked reduction in hepatic triglyceride secretion when rats are fed fish oils was explored in studies with isolated rat hepatocytes. Hepatocytes obtained from Sprague-Dawley rats fed either chow or fish oil or safflower oil were incubated in the presence of [3H]-glycerol to estimate triglyceride formation. In some experiments, various fatty acids, complexed to albumin, were added to the incubations. Similar experiments were carried out with hepatocytes from a genetic strain of hypertriglyceridemic, obese rats. In the absence of added fatty acid, hepatocytes from fish oil-fed rats produced and secreted substantially less triglyceride than cells from safflower oil-fed rats. However, the addition of 2 mmol/L Na oleate stimulated triglyceride formation similarly in both types of hepatocytes. When hepatocytes from chow fed rats were incubated with fatty acids of increasing chain length and unsaturation (oleate, linolenate, arachidonate, eicosapentaenoate, and docosahexaenoate), the latter two, which characterize the fish oil used, almost totally suppressed triglyceride formation. Coincubation with oleate partly reversed this effect. Hepatocytes from the hypertriglyceridemic rats synthesized significantly more triglyceride than hepatocytes from normal rats; however triglyceride formation was markedly reduced also in this strain of rat by feeding fish oil or by adding docosahexaenoate to hepatocytes in vitro. These studies confirm previous conclusions with perfused livers from fish oil-fed rats that showed diminished triglyceride production and secretion. These findings suggest that diversion of polyenoic acids from pathways of esterification is a major factor in the triglyceride lowering effect of fish oils.(ABSTRACT TRUNCATED AT 250 WORDS)

Eicosapentaenoic acid inhibits the secretion of triacylglycerol and of apoprotein B and the binding of LDL in Hep G2 cells

The consumption of long chain polyunsaturated fatty acids by fish oils leads to profound lowering of plasma triacylglycerol but not of plasma cholesterol. Reasons for this were investigated with the human hepatoma cell line, the Hep G2 cell. Incubations with oleic acid (18:1 n9), linoleic acid (18:2 n6) and the characteristic marine fatty acid eicosapentaenoic acid (EPA, 20:5 n3) enriched cellular triacylglycerol mass, though least with EPA. However, secretion of very low density lipoprotein (VLDL) triacylglycerol and apoprotein B (measured by formation from [3H]glycerol and [3H]leucine) was markedly inhibited by EPA. Preincubation with linoleic acid reduced VLDL triacylglycerol but not apo B secretion in comparison with oleic acid which stimulated both. A possible effect on low density lipoprotein (LDL) removal was studied by measuring [125I]LDL binding. Preincubation with either EPA or linoleic acid inhibited the saturable binding of LDL, observed with oleic acid and control incubations. The binding of lipoproteins containing chylomicron remnants was not affected by any of the fatty acids.