MAP2 is localized to the dendrites of hippocampal neurons which develop in culture

The distribution of the microtubule-associated protein MAP2 in cultured hippocampal neurons was studied using immunocytochemistry with monoclonal antibodies. MAP2 was preferentially localized to dendritic, but not axonal, processes even in single isolated cells which developed without making intercellular contacts. Hence regional differences in the molecular composition of the neuronal cytoskeleton can develop independently of cell interactions. The presence of MAP2 may be a useful marker for identifying dendrites in cell culture.

Differential patterns of memory loss among patients with Alzheimer's disease, Huntington's disease, and alcoholic Korsakoff's syndrome

Patients with Huntington's disease (HD), alcoholic Korsakoff's syndrome (KS), and Alzheimer's disease (AD) were compared with normal control subjects on a task designed to assess recognition memory for different classes of stimuli: spatial, verbal, color, pattern, and facial. In addition, recall of verbal stimuli was assessed at two delay intervals. On recognition testing, AD and KS patients were impaired on each of the five stimulus conditions. However, HD patients, though impaired on four of the recognition conditions, were unimpaired when verbal stimuli were used. On recall testing, the AD, HD, and KS groups were equally impaired at the shorter delay (15 s). However, at the longer delay (two minutes), the KS and HD patients, though still impaired relative to the normal control group, performed significantly better than the AD group.

Pharmaceutical and personal care products in groundwater, subsurface drainage, soil, and wheat grain, following a high single application of municipal biosolids to a field

Dewatered municipal biosolids (DMBs) were applied to a field at a rate of ~22 Mg dw ha(-1) in October 2008. Pharmaceuticals and personal care products (PPCPs) were monitored in groundwater, tile drainage, soil, DMB aggregates incorporated into the soil post-land application, and in the grain of wheat grown on the field for a period of ~1 year following application. Over 80 PPCPs were analyzed in the source DMB. PPCPs selected for in-depth monitoring included: antibiotics (tetracyclines, fluoroquinolones), bacteriocides (triclosan, triclocarban), beta-blockers (atenolol, propranolol, metaprolol), antidepressants (fluoxetine, citalopram, venlafaxine, sertraline), antifungals (miconazole), analgesics (acetaminophen, ibuprofen) and anticonvulsants (carbamazepine). PPCPs in tile were observed twice, ~3 weeks and 2 months post-application. Of all PPCPs measured in tile drainage, only carbamazepine, ibuprofen, acetaminophen, triclosan, triclocarban, venlafaxine, and citalopram were detected (5-74 ng L(-1)). PPCPs were not detected in groundwater >2 m depth below the soil surface, and concentrations above detection limits at 2 m depth were only observed once just after the first rain event post-application. In groundwater, all compounds found in tile, except carbamazepine, acetaminophen and citalopram, were detected (10-19 ng L(-1)). PPCPs were detected in DMB aggregates incorporated in soil up to 1 year post-application, with miconazole and fluoxetine having the lowest percent reductions over 1 year (~50%). For several compounds in these aggregates, concentration declines were of exponential decay form. No PPCPs were detected in the grain of wheat planted post-application on the field. No PPCPs were ever detected in water, soil or grain samples from the reference plot, where no DMB was applied.

Dissociations between skill learning and verbal recognition in amnesia and dementia

Patients with Huntington's disease (HD), patients with alcoholic Korsakoff's syndrome, and normal control subjects were compared on tests of skill learning (mirror reading) and verbal recognition. Like previously reported results, the patients with Korsakoff's syndrome acquired the mirror-reading skill at a normal rate but were severely impaired in their recognition of the words used on the mirror-reading task. In contrast to the amnesic patients, the demented patients with HD were retarded in their ability to acquire this skill but showed normal verbal recognition. Besides emphasizing substantial differences in the anterograde substantial differences in the anterograde memory disorders of these two patient populations, the results suggest that the memory disorder of patients with HD may appear much more severe when recall rather than recognition test paradigms are employed. This failure of recall by the patients with HD may be due to an inability to generate strategies necessary to search their short- and long-term memories.

Endoscopic retrograde brush cytology. A new technique

Endoscopic retrograde cholangiopancreatography has been shown to be a very valuable adjunct in the diagnosis of malignancy involving the biliary and/or pancreatic ductal system. However, characteristic endoscopic retrograde cholangiopancreatography radiographic findings associated with malignant strictures are frequently not specific and cytological confirmation becomes essential for the diagnosis. Unfortunately, the current overall diagnostic yield of positive cytology in such circumstances ranges from 18%-56% depending on the technique. A new brush device has been designed which is uniquely adapted to pancreaticobiliary strictures of varying anatomical configurations. This study shows results using this new cytology brush in a series of 53 patients with pancreaticobiliary malignancy. A significant improvement in the cytological yield of tumor confirmation was obtained with a diagnostic sensitivity of 70% and specificity of 100% using the new brush technique.

Physical function and fear of falling after hip fracture rehabilitation in the elderly

OBJECTIVE

The purpose of this study was to determine the relationship between physical function and fall-related self-efficacy in older patients with a hip fracture who are undergoing an intensive rehabilitation program.

DESIGN

We used a prospective cohort study over 12 mo to determine the effect of a specialized hip fracture rehabilitation program in a geriatric hospital on physical function and fear of falling. Fifty-six patients were admitted consecutively from acute care. Physical function was assessed using the Functional Independence Measure, and fall-related self-efficacy was measured using two scales: the Falls-Efficacy scale and the Activities-Specific Balance Confidence scale. We also used the Vitality scale to measure quality of life. All measures, represented by change scores, were determined at the beginning and end of the patients' rehabilitation programs.

RESULTS

Significant improvement in physical function and fall self-efficacy was observed. The Vitality scale was also improved after rehabilitation. The Falls-Efficacy scale appeared to be more sensitive to change than the Activities-Specific Balance Confidence scale, whereas no correlation was found between changes in the fall-related self-efficacy measures and the Functional Independence Measure.

CONCLUSIONS

These findings may represent a discrepancy between attention of the rehabilitation program on functional outcomes and less emphasis on confidence building behaviors. Restrictions in function from a fear of falling may negate any gains made through rehabilitation, and this could limit the long-term success of these programs and patient outcomes after hip fracture.

Brain choline in depression: in vivo detection of potential pharmacodynamic effects of antidepressant therapy using hydrogen localized spectroscopy

1. Seven subjects with depression and matched controls were studied using proton spectroscopy to test the hypothesis that choline will be elevated in depression. 2. The proton spectroscopy was repeated after recovery from depression. 3. The study confirmed a state dependent increase in choline in the brain. 4. This change may be used as an in vivo marker of change in depression.

Pharmaceutical and personal care products in tile drainage following surface spreading and injection of dewatered municipal biosolids to an agricultural field

Land application of municipal biosolids can be a source of environmental contamination by pharmaceutical and personal care products (PPCPs). This study examined PPCP concentrations/temporally discrete mass loads in agricultural tile drainage systems where two applications of biosolids had previously taken place. The field plots received liquid municipal biosolids (LMB) in the fall of 2005 at an application rate of approximately 93,500 L ha (-1), and a second land application was conducted using dewatered municipal biosolids (DMB) applied at a rate of approximately 8Mg dw ha (-1) in the summer of 2006 [corrected].The DMB land application treatments consisted of direct injection (DI) of the DMB beneath the soil surface at a nominal depth of approximately 0.11 m, and surface spreading (SS) plus subsequent tillage incorporation of DMB in the topsoil (approximately 0.10 m depth). The PPCPs examined included eight pharmaceuticals (acetaminophen, fluoxetine, ibuprofen, gemfibrozil, naproxen, carbamazepine, atenolol, sulfamethoxazole), the nicotine metabolite cotinine, and two antibacterial personal care products triclosan and triclocarban. Residues of naproxen, cotinine, atenolol and triclosan originating from the fall 2005 LMB application were detected in tile water nearly nine months after application (triclocarban was not measured in 2005). There were no significant differences (p>0.05) in PPCP mass loads among the two DMB land application treatments (i.e., SS vs. DI); although, average PPCP mass loads late in the study season (>100 days after application) were consistently higher for the DI treatment relative to the SS treatment. While the concentration of triclosan (approximately 14,000 ng g(-1) dw) in DMB was about twice that of triclocarban (approximately 8000 ng g(-1) dw), the average tile water concentrations for triclosan were much higher (43+/-5 ng L(-1)) than they were for triclocarban (0.73+/-0.14 ng L(-1)). Triclosan concentrations (maximum observed in 2006 approximately 235 ng L(-1)) in tile water resulting from land applications may warrant attention from a toxicological perspective.

Methylphenidate for gait impairment in Parkinson disease: a randomized clinical trial

BACKGROUND

There is a paucity of therapies for gait impairment in Parkinson disease (PD). Open-label studies have suggested improved gait after treatment with methylphenidate (MPD).

OBJECTIVE

To evaluate the efficacy of MPD for the treatment of gait impairment in PD.

METHODS

Twenty-seven subjects with PD and moderate gait impairment were screened for this 6-month placebo-controlled, double-blind study. Subjects were randomly assigned to MPD (maximum, up to 80 mg/day) or placebo for 12 weeks and crossed over after a 3-week washout. The primary outcome measure was change in a gait composite score (stride length + velocity) between groups at 4 and 12 weeks. Secondary outcome measures included changes in motor function, as measured by the Unified Parkinson's Disease Rating Scale (UPDRS), Freezing of Gait Questionnaire (FOGQ), number of gait-diary freezing episodes, and measures of depression, sleepiness, and quality of life. Three-factor repeated-measures analysis of variance was used to measure changes between groups.

RESULTS

Twenty-three eligible subjects with PD were randomized and 17 completed the trial. There was no change in the gait composite score or treatment or time effect for any of the variables. Treatment effect was not modified by state or study visit. Although there was a trend for reduced frequency of freezing and shuffling per diary, the FOGQ and UPDRS scores worsened in the MPD group compared to placebo. There was a marginal improvement in some measures of depression.

CONCLUSIONS

MPD did not improve gait and tended to worsen measures of motor function, sleepiness, and quality of life.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence for the lack of benefit of MPD on PD-associated gait impairment.

CLINICAL TRIAL REGISTRATION

NCT00526630.

Specific cleavage of immunoglobulin G by copper ions

The hinge region of a recombinant-DNA-produced human IgG1 (Campath 1H) is specifically cleavable at a single copper-sensitive peptide bond, yielding a distinct fragment resolved by size-exclusion high-performance liquid chromatography. This novel metal ion-catalysed cleavage at slightly alkaline pH is inhibited by EDTA and its rate is reduced at slightly acidic conditions (pH 5-6) and accelerated by increasing concentrations of cupric ion and higher temperature. Complete cleavage was observed after incubation at pH 8 for 24 h with 1 mM CuCl2. Sequence analysis determined the cleavage site to be the Lys226-Thr227 bond in the hinge-region sequence DKTHT. Cleavage of other IgGs was observed to varying degrees, and specific cleavage of synthetic peptides containing this pentapeptide sequence was also observed.

Continuous intravenous infusion of morphine for severe dyspnea

We describe eight patients who had terminal lung cancer causing severe dyspnea unrelieved by oxygen, nonnarcotic drugs, or intermittent bolus narcotics. We treated these patients with continuous intravenous infusion of morphine, beginning with bolus IV injections of 1 or 2 mg of morphine every 5 to 10 minutes until the patient reported relief. A continuous morphine infusion was then started, with the hourly dose equal to 50% of the cumulative bolus dose. Vital signs, degree of sedation, and blood gases were serially followed. Six patients achieved good dyspnea relief, one had moderate relief, and one had a poor response. Variable changes were noted in the PaO2, whereas PaCO2 steadily increased in five of seven patients, and pH decreased in six. There was little change in systolic blood pressure or pulse, and only one individual had less than 10 respirations per minute. The major side effect of treatment was sedation, treated by temporarily discontinuing morphine until the patients' mental status improved and then restarting the infusion at a 50% lower hourly morphine dose. Mean time of study was 30 hours (range 16 to 87 hours). Seven of the eight study patients died during treatment. Whether morphine therapy shortened survival is uncertain. We conclude that continuous morphine infusion is effective therapy for severe dyspnea. The treatment is ethically justified. Relief of suffering is the primary goal of therapy, and less risky treatments are unavailable.

Isolation and characterization of intact mitochondria from neonatal rat brain

Poor outcome after neonatal brain injury may be associated with alterations in mitochondrial function. Thus, isolated mitochondria have been a useful tool in understanding the underlying mechanisms of mitochondrial dysfunction. However, isolation and characterization of mitochondria from neonatal rat brain are not fully described. Thus, the aim of this study was to develop a rapid method for the isolation and characterization of functional mitochondria from neonatal rat brain. Mitochondria were isolated from 7-day-old rat brain weighing approximately 500 mg using a discontinuous Percoll density gradient. Brains were homogenized in 12% Percoll/sucrose buffer and layered onto a 26% Percoll/40% Percoll gradient followed by centrifugation. Four methods were used for assessing mitochondrial integrity and function: (1) electron microscopy to assess the morphology of the mitochondria and to determine the relative purity of the preparation; (2) fluorescence of chloromethyl-X-rosamine (Mito Tracker Red) in mitochondria as an indicator of mitochondrial membrane potential (Delta psi(m)); (3) state 3 and 4 respiration; and (4) protein import into mitochondria using an in vitro-synthesized mitochondrial malate dehydrogenase (mMDH). These studies demonstrated that the morphology of mitochondria is maintained with intact outer membranes and well-developed cristae, and Delta psi(m) is preserved. Respiration measurements revealed tightly coupled mitochondria with a respiration control ratio (RCR) of 4.1+/-0.18 (n=6). Import of precursor mMDH into mitochondria increased in a time-dependent manner maximizing at 15 min. The results indicate that neonatal brain mitochondria isolated using this method are well coupled, morphologically intact and are capable of protein import across the outer and inner mitochondrial membranes.

Single case evaluation of the effects of aromatherapy and massage on disturbed behaviour in severe dementia

Aromatherapy and massage could provide a useful addition to psychological therapeutic interventions with clients suffering from dementia. The effects of aromatherapy and massage on disturbed behaviour in four individuals with severe dementia were evaluated using a single-case research design. Each participant received 10 treatment sessions of aromatherapy, aromatherapy and massage combined, and massage alone. The effects on each individual's behaviour in the hour following treatment were assessed against 10 'no treatment' control sessions. Reliable individualized disturbed behaviour scales were designed. The effects of the treatments were mixed. The opinion of the staff providing treatment was that all participants benefited. On close scrutiny, only one of the participants benefited from the aromatherapy and massage to a degree that reached statistical significance. In two of the cases aromatherapy and massage led to an increase in agitated behaviour. The importance of the single case study approach with this client group is discussed.

Directory of clinical databases: improving and promoting their use

BACKGROUND

The controversy surrounding the actual and potential use of clinical databases partly reflects the huge variation in their content and quality. In addition, use of existing clinical databases is severely limited by a lack of knowledge of their availability.

OBJECTIVES

To develop and test a standardised method for assessing the quality (completeness and accuracy) of clinical databases and to establish a web based directory of databases in the UK.

METHODS

An expert group was set up (1). to establish the criteria for inclusion of databases; (2). to develop a quality assessment instrument with high content validity, based on epidemiological theory; (3). to test empirically, modify, and retest the acceptability to database custodians, face validity and floor/ceiling effects; and (4). to design a website.

RESULTS

Criteria for inclusion of databases were the provision of individual level data; inclusion in the database defined by a common circumstance (e.g. condition, treatment), an administrative arrangement, or an adverse outcome; and inclusion of data from more than one provider. A quality assessment instrument consisting of 10 items (four on coverage, six on reliability and validity) was developed and shown to have good face and content validity, no floor/ceiling effects, and to be acceptable to database custodians. A website (www.docdat.org) was developed. Indications over the first 18 months (number of visitors to the site) are that it is increasingly popular. By November 2002 there were around 3500 hits a month.

CONCLUSIONS

A website now exists where visitors can identify clinical databases in the UK that may be suitable to meet their aims. It is planned both to develop a local version for use within a hospital and to encourage similar national systems in other countries.

Properties of two nuclear pet mutants affecting expression of the mitochondrial oli1 gene of Saccharomyces cerevisiae

This study details the characteristics of two temperature-conditional pet mutants of yeast, strains ts1860 and ts379, which at the non-permissive temperature show deficiencies in the formation of three mitochondrially encoded subunits of the ATP synthase complex. By analysis of mitochondrial translation products, and of mitochondrial transcription in temperature shift experiments from the permissive (22 degrees C) to the non-permissive (36 degrees C) temperature, it was concluded that the nuclear mutations in both mutants primarily inhibit synthesis of ATP synthase subunit 9, and that reductions in subunit 8 and 6 synthesis are secondary pleiotropic effects. Following transfer to 36 degrees C, cells of mutant ts379 display a near complete inhibition of subunit 9 synthesis within 1 h, coincident with a marked reduction in the level of the cognate oli1 mRNA. On the other hand, near complete inhibition of subunit 9 synthesis in strain ts1860 occurs after 3 h at 36 degrees C, at which time there is little change in the level of subunit 9 mRNA. In both mutants the mRNA levels for subunits 6 and 8 are not significantly affected at the time of inhibition of subunit 9 synthesis. Provision of an alternative source of subunit 8, translated extra-mitochondrially for import into the organelle, does not overcome the mutant phenotype of either mutant at 36 degrees C, confirming that subunit 8 is not the sole or primary deficiency in each mutant. The mutants indicate that the products of a least two nuclear genes (designated AEP1 and AEP2) are required for the expression of the mitochondrial oli1 gene and the synthesis of subunit 9. (ABSTRACT TRUNCATED AT 250 WORDS)

Endoscopic treatment of post-liver transplantation biliary leaks with stent placement across the leak site

BACKGROUND

Biliary tract leaks occur in over 10% of patients undergoing liver transplantation and are the most common cause of biliary tract-related death in these patients. A number of treatment options are available, but a standard approach has not been established.

METHODS

Twenty-six patients were retrospectively studied who had post-transplantation leaks develop with special reference to those who underwent endoscopic placement of a "leak-bridging" stent.

RESULTS

Endoscopic retrograde cholangiography was performed in all cases with no procedure-related complications. Twenty-four patients had a leak-bridging stent, 1 a transpapillary stent, and 1 a nasobiliary drain. Leak resolution occurred in 23 cases (88%) after initial stent placement. The median time to stent removal was 8 weeks. Three patients did not respond to initial treatment; 2 were successfully treated with another stent and a single patient required surgical repair. Four deaths occurred during follow-up, all unrelated to the biliary leak.

CONCLUSIONS

Placement of a leak-bridging stent is a safe and effective initial treatment for post-liver transplantation biliary leaks.

Temozolomide in the treatment of solid tumours: current results and rationale for dosing/scheduling

This review examines the current evidence for the use of temozolomide in the treatment of solid tumours. The possible molecular and clinical advantages of temozolomide are identified and the molecular mechanism of temozolomide resistance is explored. Attempts to maximise efficacy have led to manipulation of both dosage and drug scheduling and the evidence for the various strategies is reviewed. Finally, the potential role of combination therapy is considered.

Evidence for an [Fe]-type hydrogenase in the parasitic protozoan Trichomonas vaginalis

The hydrogenase of the pathogenic protozoan Trichomonas vaginalis was extracted and partially purified. The catalytic and spectroscopic properties of the enzyme indicate that it belongs to the class of [Fe]-hydrogenases, rather than the [NiFe]-hydrogenases. The hydrogenase activity was highly sensitive to carbon monoxide, 50% inhibition being attained by 1 microM CO. The EPR spectrum of the most active fractions from chromatography, after reduction by hydrogen and partial reoxidation under argon, showed an EPR spectrum at g = 2.10, 2.04, 2.00. This unusual spectrum is characteristic of the 'H-cluster', as seen in [Fe]-hydrogenases of anaerobic bacteria such as Clostridium spp.

Brominated flame retardants and perfluoroalkyl acids in groundwater, tile drainage, soil, and crop grain following a high application of municipal biosolids to a field

Dewatered municipal biosolids (DMB) were applied at a rate of 22Mgdwha^-1 to an agricultural field in fall 2008. Concentrations of polybrominated diphenyl ethers (PBDEs; BDE-47, -99, -100, -153, -154, -183, -197, -207, -209), other brominated flame retardants (BFRs; HBB, PBEB, DBDPE, BTBPE) and perfluoroalkyl acids (PFAAs; PFHxS, PFOS, PFDS, PFOSA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA, PFTA) were monitored in tile drainage, groundwater (2m, 4m and 6m depth), soil cores (0-0.3m) pre- and post-application, DMB aggregates incorporated into the soil post-application, and in wheat (Triticum spp.) planted post-application. Several compounds were detected in soil and water pre-application and on a reference field plot. PBDEs, other BFRs and PFAAs were detected in tile drainage and 2m groundwater throughout the post-application study period; a few PBDEs were also detected sporadically at lower depths in groundwater. Some of these compounds had not been detected pre-application, while some exceeded reference field plot/pre-application levels (some significantly (p<0.05) in tile drainage); both cases indicating biosolid-based water contamination. In DMB aggregates, several PBDE congeners were found to have dissipated exponentially, with reductions >90% in many of them within 1year post-application. Exponential dissipation of other BFRs and PFAAs in DMB aggregates were not significant. No PBDEs, other BFRs, or PFAAs were detected in wheat grain.

Characterization of a yeast nuclear gene, AEP2, required for accumulation of mitochondrial mRNA encoding subunit 9 of the ATP synthase

The temperature-conditional pet mutant, ts379, of Saccharomyces cerevisiae fails to synthesize mitochondrial ATP synthase subunit 9 at the restrictive temperature due to mutation of a single nuclear locus, AEP2. The inability to synthesize subunit 9 correlates with a lowered accumulation of the cognate oli1 mRNA indicating that the AEP2 product is involved in oli1 transcript maturation or stabilization. The AEP2 gene has been isolated in this study from a wild-type yeast genomic library by genetic complementation of ts379 at the restrictive temperature. A 1,740 nucleotide open-reading frame was observed that encodes a basic, hydrophilic protein of 67,534 Da which possesses a putative mitochondrial address signal. Disruption of chromosomal DNA within this reading frame produced a non-conditional respiratory mutant unable to synthesize subunit 9, identifying the AEP2 gene. Hybridization analyses indicate that AEP2 is located on chromosome XIII and produces a 2.1 kb poly(A)+ transcript. Two additional open-reading frames were found in close proximity to that of AEP2. The three open-reading frames shared no significant homology with entries in several data bases.

Use of bilevel positive airway pressure in out-of-hospital patients

OBJECTIVE

To evaluate the utility of bilevel positive airway pressure (BiPAP) in the out-of-hospital treatment of patients with presumed congestive heart failure (CHF).

METHODS

This was a prospective, sequential, parallel trial in an urban setting served by a single emergency medical services (EMS) system between January 4 and April 15, 1999. A convenience sampling of adults who were transported by rescue units judged to be in CHF by treating emergency medical technicians trained in advanced life support (ALS EMTs) was included. Rescue squads were divided into demographically matched pairs, and one of each was equipped with a BiPAP ventilatory support unit. Bilevel positive airway pressure therapy was added to the existing treatment protocols for eligible study patients. Main outcome measures were out-of-hospital treatment time, oxygen saturation changes, hospitalization length, need for endotracheal intubation, mortality rate, and ease of use of the device by EMS personnel.

RESULTS

Sixty-two of 71 enrolled patients completed the study. Out-of-hospital treatment times did not differ between groups (31.2 minutes vs 31.4 minutes; p = 0.931). The difference between pre- and post-treatment oxygen saturation levels was greater for the BiPAP group (13.71%) than the control group (6.69%) (p < 0.05). There was no statistical difference between groups in the length of hospital stay [control: 7.63 days, vs BiPAP: 6.33 days, p = 0.48], the intubation rate [control: 7 of 25 (28%) vs BiPAP: 4 of 37 (11%), p = 0.10], or death rate [control: 2 of 24, vs BiPAP: 6 of 37, p = 0.46]. All of the ALS EMTs who used BiPAP thought that it was safe to use, and 97% thought it was easy and appeared to improve patients' dyspnea and respiratory distress.

CONCLUSIONS

ALS EMTs can be trained to deliver noninvasive ventilation with BiPAP, find it easy to apply, and believe that it helps relieve dyspnea in patients with suspected CHF.

Identification of mitochondrial genes in Trypanosoma brucei and homology to cytochrome c oxidase II in two different reading frames

We have determined the nucleotide sequence of a 3.3 kilobase segment of the kDNA maxicircle of Trypanosoma brucei brucei 164. The nucleotide sequence and its predicted translated sequence have homology to cytochrome c oxidase subunits I and II (CO I and II) and mammalian unidentified reading frame 1 (URF 1). Amino acid homology to CO II extends for 170 residues from the amino terminus in one reading frame and then continues in another reading frame for 39 residues to the carboxyl terminus. Similar results have been obtained for Leishmania tarentolae [de la Cruz, V.F., Neckelmann, N. and Simpson, L. (1984) J. Biol. Chem., in press] and T. brucei 427 [Hensgens, L.A.M., Brackenhoff, J., De Vries, B.F., Sloof, P., Tromp, M.C., Van Boom, J.H. and Benne, R. (1984) Nucleic Acids Res. 12, 7327-7344]. This may indicate that novel events are required for expression of this gene. Amino acid homology to URF 1 exists predominantly at the amino terminal end although no corresponding AUG codon occurs in this area. An alternative initiation codon may therefore be utilized by trypanosome mitochondria. Two other open reading frames (ORFs) were detected and these are discussed with reference to transcripts from this region. ORFs corresponding to transcripts are organized compactly and are distributed more equally on both strands compared to ORFs of other mitochondrial systems.

The use of immobilized lectins in the separation of Staphylococcus aureus, Escherichia coli, Listeria and Salmonella spp. from pure cultures and foods

Lectins from Helix pomatia, Canavalia ensiformis, Agaricus bisporus and Triticum vulgaris agglutinated cultures of Staphylococcus aureus, Escherichia coli, Listeria and Salmonella spp. This agglutination was specific as it was inhibited (except with A. bisporus lectin) by the competing sugar substrates. The ability of three of these lectins, immobilized on a variety of supports, to separate these micro-organisms from pure cultures was investigated. Immobilization of the lectins on magnetic microspheres was the most effective method. Immobilized T. vulgaris lectin bound 87-100% of cells from cultures of L. monocytogenes, 80-100% of Staph. aureus, 33-45% of Salmonella spp. and 42-77% of E. coli. The A. bisporus lectin bound 31-63% of cells in cultures of L. monocytogenes, 83% of Staph. aureus but only 3-5% of the salmonella cells. Similarly H. pomatia lectin bound greater than 92% of Staph. aureus and 64% of L. monocytogenes cells but was poor at binding the Gram-negative organisms. This preference for binding Gram-positive organisms was confirmed when mixed cultures were studied. The T. vulgaris lectin was effective in removing L. monocytogenes (43%) and Staph. aureus (26%) from diluted milk and Salmonella (31-54%) from raw egg. Agaricus bisporus lectin removed L. monocytogenes from undiluted milk (10-47%) or ground beef (32-50%).