Intranuclear inclusions of expanded polyglutamine protein in spinocerebellar ataxia type 3

The mechanism of neurodegeneration in CAG/polyglutamine repeat expansion diseases is unknown but is thought to occur at the protein level. Here, in studies of spinocerebellar ataxia type 3, also known as Machado-Joseph disease (SCA3/MJD), we show that the disease protein ataxin-3 accumulates in ubiquitinated intranuclear inclusions selectively in neurons of affected brain regions. We further provide evidence in vitro for a model of disease in which an expanded polyglutamine-containing fragment recruits full-length protein into insoluble aggregates. Together with recent findings from transgenic models, our results suggest that intranuclear aggregation of the expanded protein is a unifying feature of CAG/polyglutamine diseases and may be initiated or catalyzed by a glutamine-containing fragment of the disease protein.

Machado-Joseph disease gene product is a cytoplasmic protein widely expressed in brain

Machado-Joseph disease (MJD) is one of at least six neurodegenerative diseases caused by expansion of a CAG repeat encoding a polyglutamine tract in the disease protein. To study the molecular mechanism of disease, we isolated both normal and expanded repeat MJD1 cDNAs, and generated antiserum against the recombinant gene product, called ataxin-3. Using this antiserum, we demonstrate that in disease tissue, both the normal and mutant ataxin-3 protein are expressed throughout the body and in all regions of the brain examined, including areas generally spared by disease. In brain, certain regions (the striatum, for example) express ataxin-3 in only a limited subset of neurons. Immunolocalization studies in normal and disease brain, and in transfected cells, indicate that ataxin-3 is predominantly a cytoplasmic protein that localizes to neuronal processes as well. We conclude that in MJD, as in other polyglutamine repeat diseases, cellular expression of the disease gene is not itself sufficient to cause neuronal degeneration; other cell-specific factors must be invoked to explain the restricted neuropathology seen in MJD. The restricted expression of ataxin-3 in certain regions, however, may influence the pattern of neurodegeneration and provide clues to the protein's function.

Comparison of 99mTc infecton imaging with radiolabelled white-cell imaging in the evaluation of bacterial infection

BACKGROUND

Bacterial infection can pose a substantial diagnostic dilemma. Techniques involving radiolabelled leucocytes can pinpoint the site of inflammation. However, previous radiolabelling techniques have failed to distinguish between bacterial-mediated infection and non-bacterial inflammation. To overcome this difficulty, we have studied a radiopharmaceutical, technetium-99m (99mTc) Infecton, which is based on the antibiotic ciprofloxacin.

METHODS

We used this agent to image bacterial infection in 56 patients (one twice) with known or suspected sites of infection. We then compared the imaging results of these patients with those from a radiolabelled leucocyte study.

FINDINGS

The concordance rate was 68% (39 out of 57 images). In 18 discordant results 99mTc Infecton was correctly positive in 8 out of 9 positive studies and correctly negative in 4 out of 9 negative studies. 4 out of 5 of the falsely negative studies were in patients who had taken antibiotics for over 7 days. We found that 99mTc Infecton gave better imaging results than radiolabelled leucocytes. Comparison between 99mTc Infecton and leucocyte imaging gave sensitivities of 84% and 81%, and specificities of 96% and 77%, respectively.

INTERPRETATION

We believe that the specificity 99mTc Infecton confers for bacterial infection and its ease of administration are the main advantages of this new agent.

Imaging bacterial infection with (99m)Tc-ciprofloxacin (Infecton)

AIMS

The diagnosis of deep seated bacterial infections, such as intra-abdominal abscesses, endocarditis, and osteomyelitis, can be difficult and delayed, thereby compromising effective treatment. This study assessed the efficacy of a new radioimaging agent, Tc-99m ciprofloxacin (Infecton), in accurately detecting sites of bacterial infection.

METHODS

Eight hundred and seventy nine patients with suspected bacterial infection underwent Infecton imaging and microbiological evaluation. The sensitivity and specificity of Infecton in detecting sites of bacterial infection were determined with respect to Centres of Disease Control, World Health Organisation, and Dukes's criteria.

RESULTS

Five hundred and seventy four positive and 295 negative images were produced. These included 528 true positives, 46 false positives, 205 true negatives and 90 false negatives, giving an overall sensitivity of 85.4% and a specificity of 81.7% for detecting infective foci. Sensitivity was higher (87.6%) in microbiologically confirmed infections.

CONCLUSIONS

Infecton is a sensitive technique, which aids in the earlier detection and treatment of a wide variety of deep seated bacterial infections. The ability to localise infective foci accurately is also important for surgical intervention, such as drainage of abscesses. In addition, serial imaging with Infecton might be useful in monitoring clinical response and optimising the duration of antimicrobial treatment.

Evaluation of the efficacy of 99mTc-Infecton, a novel agent for detecting sites of infection

AIMS

To determine the sensitivity and specificity of 99mTc-Infecton (Infecton), a novel ciprofloxacin based imaging agent, in detecting sites of infection.

METHODS

Ninety patients thought to be suffering from a variety of infections were administered 300-400 MBq of Infecton intravenously. Whole body images were taken one and four hours later. Appropriate specimens were taken for microbiological investigations. Statistical analysis was performed using a computer statistical package.

RESULTS

Ninety eight Infecton images were produced. Forty one of these were positive, including three false positives, where the patients had non-infective conditions. Fifty seven negative images were obtained, of which 41 were true negatives and 16 were false negatives, having definite evidence of infection. Thus, Infecton imaging has a sensitivity of 70.3% and a specificity of 93.1% for detecting infective foci. The positive and negative predictive values were 92.6% and 71.9%, respectively.

CONCLUSION

Infecton imaging is a new diagnostic tool that is specific for detecting sites of bacterial infection in the body. The high positive predictive value displayed by the technique is clinically important because a positive image strongly supports a diagnosis of bacterial infection. A negative result does not rule out an infection, and may be a result of previous or current antibiotic treatment and/or infection with organisms that do not take up Infecton. Infecton imaging has major advantages over well established imaging techniques, including radiolabelled leucocytes, and may prove to be a superior method for localising bacterial infections.

Dietary yeast RNA supplementation reduces mortality by Aeromonas hydrophila in rohu (Labeo rohita L.) juveniles

A feeding trial was conducted for 60 days to delineate the effect of dietary ribonucleic acid or chitin on haematological parameters, phagocyte respiratory burst and resistance to Aeromonas hydrophila of Labeo rohita juveniles. One hundred and twenty-six (avg. wt. 13.40 +/- 0.17 g) juveniles were randomly distributed in six treatment groups, each one in three replicates. Six isonitrogenous (crude protein: 34.34-35.37%) and isocaloric (414-425 kcal 100 g(-1)) purified diets were prepared with different concentrations of either ribonucleic acid or chitin except the control group, viz., control, T1 (0.1% ribonucleic acid), T2 (0.2% ribonucleic acid), T3 (0.4% ribonucleic acid), T4 (25 mg chitin kg (-1)) and T5 (50 mg chitin kg (-1)). Weight gain %, specific growth rate, feed efficiency ratio, protein efficiency ratio did not vary significantly (P > 0.05) among the experimental groups. Haemoglobin content and total erythrocyte count were observed within the normal range and were not influenced by the dietary immunostimulants. Highest total leukocyte count was found in the T(3) group. The immunomodulatory effects of dietary immunostimulants were studied by using nitroblue tetrazolium (NBT) assay and serum parameters, namely total protein, albumin, globulin and A/G ratio. The respiratory burst activity (NBT) of blood phagocytes was highest in the T3 group followed by the T2 group, which varied significantly (P < 0.05) from other groups. Significantly (P < 0.05) higher total protein, globulin and lower A/G ratio was observed in the T(3) group. The relative percent survival after challenging with Aeromonas hydrophila was highest in the T3 group, compared to the control group, followed by the T2 group. The results indicate that dietary ribonucleic acid at 0.4% enhances phagocyte respiratory burst and protection of Labeo rohita juveniles to challenge by A. hydrophila.

Enterotoxigenicity of mature 45-kilodalton and processed 35-kilodalton forms of hemagglutinin protease purified from a cholera toxin gene-negative Vibrio cholerae non-O1, non-O139 strain

Cholera toxin gene-negative Vibrio cholerae non-O1, non-O139 strain PL-21 is the etiologic agent of cholera-like syndrome. Hemagglutinin protease (HAP) is one of the major secretory proteins of PL-21. The mature 45-kDa and processed 35-kDa forms of HAP were purified in the presence and absence of EDTA from culture supernatants of PL-21. Enterotoxigenicities of both forms of HAP were tested in rabbit ileal loop (RIL), Ussing chamber, and tissue culture assays. The 35-kDa HAP showed hemorrhagic fluid response in a dose-dependent manner in the RIL assay. Histopathological examination of 20 microg of purified protease-treated rabbit ileum showed the presence of erythrocytes and neutrophils in the upper part of the villous lamina propria. Treatment with 40 microg of protease resulted in gross damage of the villous epithelium with inflammation, hemorrhage, and necrosis. The 35-kDa form of HAP, when added to the lumenal surface of rat ileum loaded in an Ussing chamber, showed a decrease in the intestinal short-circuit current and a cell rounding effect on HeLa cells. The mature 45-kDa form of HAP showed an increase in intestinal short-circuit current in an Ussing chamber and a cell distending effect on HeLa cells. These results show that HAP may play a role in the pathogenesis of PL-21.

Curative effect of dexamethasone-cyclophosphamide pulse therapy for the treatment of pemphigus vulgaris

In 1982, five patients having pemphigus vulgaris, four men and one woman, ranging in age between 16 and 48 years, were treated with an arbitrary regimen designed by us. The regimen consisted of giving 100 mg dexamethasone in 500 mL of 5% glucose by a slow intravenous infusion on three consecutive days, along with 500 mg cyclophosphamide on one day only. Such dexamethasone-cyclophosphamide pulses (DCP) were meant to be given once a month, but most patients were not regular in this treatment. In between these pulses the patients received only 50 mg cyclophosphamide orally per day. Oral corticosteroids were given only when necessary. After having received a total of 14 to 48 DCPS, further treatment for pemphigus was withdrawn. All the patients are in continuous clinical remission for the last 4 to 9 years and without any treatment for 2 to 7 years. Further studies on more pemphigus patients have yielded similar results suggesting that it may be possible to cure pemphigus.

Treatment of prosthetic valve infective endocarditis due to multi-resistant Gram-positive bacteria with linezolid

OBJECTIVES

Clinical experience with linezolid in the treatment of infective endocarditis either alone or in combination with other agents is limited. We describe our experience in the treatment of two patients with IE due to multi-resistant Gram-positive bacteria.

METHODS

One patient with MRSE and one with VRE endocarditis were treated with regimens containing linezolid. The killing kinetics of linezolid in combination with gentamicin or vancomycin against isolates of Staphylococcus epidermidis and Enterococcus faecalis were analysed in vitro.

RESULTS

Clinical response and eradication of bacteraemia was achieved with linezolid therapy in both patients. Time-kill curve studies showed that linezolid was bacteriostatic against the MRSE and VRE isolates used. Combination with gentamicin or vancomycin did not produce synergy or antagonism but at best only marginal additive effect.

CONCLUSIONS

Although bacteriostatic, linezolid provides an important therapeutic option in IE due to multi-resistant Gram-positive pathogens. It challenges the conventional wisdom that bactericidal synergy is required for the effective treatment of most cases of IE due to Gram-positive organisms.

Determination of anthelmintic activity of the leaf and bark extract of tamarindus indica linn

The aim of the present study was to evaluate the anthelmintic activity of ethanolic and aqueous extract of leaves and bark of Tamarindus indica Linn using Pheretima posthuma and Tubifex tubifex as test worms. The time of paralysis and time of death were studied and the activity was compared with piperazine citrate as reference standard. The alcohol and aqueous extract of bark of Tamarindus indica exhibited significant anthelmintic activity as evidenced by decreased paralyzing time and death time. The results thus support the use of Tamarindus indica as an anthelmintic agent.

Nosocomial empyema caused by Clostridium difficile

Pleural infection with Clostridium difficile is extremely rare. A case of nosocomial empyema following chest drain insertion in a 46 year old man is described. The potential of C difficile to cause extra-intestinal infections should be recognised and its isolation from other sites should not be ignored.

Rapid diagnosis of Campylobacter pyloridis infection

Images

Opsonophagocytosis of Campylobacter pylori

The opsonic activity of human serum from various sources against Campylobacter pylori was compared. All sera, whether from control subjects with no symptoms of gastritis or peptic ulceration, or from symptomatic patients from whom C. pylori had or had not been isolated, opsonised C. pylori equally well. Opsonisation depended on the alternative pathway of complement activation but not on antibody. These findings suggest that antibody plays no role in protection against C. pylori and that the presence of antibody in patients' sera is mainly of diagnostic value.

Calcium and magnesium levels during automated plateletpheresis in normal donors

It is well known that citrate induces ionized hypocalcaemia by the chelating effect during plateletpheresis. However, the kinetics of serum magnesium (Mg) ions has not been well documented. We, therefore, evaluated biochemical changes in healthy donors during plateletpheresis procedure. Ten healthy donors underwent plateletpheresis on continuous cell separator (CS3000, Baxter, Round Lake, IL, USA) and 10 on intermittent flow cell separator (MCS 3p, Hemonetics, Braintree, MA, USA). Serum levels of total and ionized calcium (tCa and iCa, respectively) and Mg (tMg and iMg, respectively) were measured before, during and after the procedures. Although, the fall in tCa (from 2.62 +/- 0.12 to 2.36 +/- 0.12 mmol L(-1)) and tMg (from 0.89 +/- 0.01 to 0.79 +/- 0.01 mmol L(-1)) was modest and not significant; drop in iCa (from 1.33 +/- 0.1 to 0.84 +/- 0.1 mmol L(-1)) and iMg (from 0.53 +/- 0.01 to 0.35 +/- 0.1 mmol L(-1)) was statistically significant (P < 0.001). There were no significant differences observed between the CS3000 and MCS 3p cell separators regarding the fall in Ca and Mg. None of the donors experienced any adverse reactions during the procedures. In the study, an acute ionized hypocalcaemia and hypomagnesaemia have been observed after the plateletpheresis; therefore, measurement of both the ions may be monitored. However, there is no justification for prophylactic supplementation of either of these elements.

Not everything acid fast is Mycobacterium tuberculosis--a case report

The Ziehl-Neelsen (ZN) stain is important in identifying organisms that are acid fast, principally Mycobacterium tuberculosis. However, decolorisation with a weaker acid concentration (for example 1% hydrochloric acid), often used in ZN staining in histology, can result in a wider variety of organisms appearing acid fast and can be a cause of misidentification. To illustrate this point, a patient is described with pulmonary nocardiosis who was misdiagnosed as having tuberculous empyema on pleural biopsy.

Campylobacter pylori in esophagus, antrum, and duodenum. A histological and microbiological study

Two hundred forty-six patients with a wide range of upper gastrointestinal tract disorders were investigated for the presence of Campylobacter pylori infection in esophagus, gastric antrum, and duodenum. C. pylori was identified in 52% of patients in at least one site, and microbiological and histological techniques were used to exclude the presence of the organism. Esophageal infection was not significant and is probably due to reflux. Antral C. pylori was significantly associated with active gastritis and active duodenitis and is possibly pathogenic.

Effects of Petroleum Ether Extract of Amorphophallus paeoniifolius Tuber on Central Nervous System in Mice

The central nervous system activity of the petroleum ether extract of Amorphophallus paeoniifolius tuber was examined in mice, fed normal as well as healthy conditions. The petroleum ether extract of Amorphophallus paeoniifolius tuber at the doses of 100, 300 and 1000 mg/kg showed significant central nervous system activity in mice.

Polymicrobial brain abscess involving Haemophilus paraphrophilus and Actinomyces odontolyticus

A case of brain abscess involving Haemophilus paraphrophilus and Actinomyces odontolyticus is presented. This combination of organisms has not previously been described. All brain abscess specimens should routinely be processed rapidly and cultured for a prolonged period to ensure recovery of fastidious organisms which may have implications for antibiotic therapy.

Diagnosis and treatment of cervical intraepithelial neoplasia in a single visit

We evaluated the diagnostic and therapeutic efficacy of large loop excision of the transformation zone (LLETZ) performed in the first visit (see and treat policy) as compared to LLETZ treatment performed as an interval procedure. Data of 248 patients were analyzed of which 206 patients had LLETZ. Two thirds of the procedures were performed at the first visit. Of all the women who had the 'see and treat policy' 94.9% were diagnosed to have cervical intraepithelial neoplasia (CIN) on histology compared to 90.8% in the interval treatment group. A total of 3 (1.4%) patients were detected to have microinvasive carcinoma. There was no difference in the immediate postoperative complication rate, overtreatment rate and need of repeat treatment in both the groups. Single visit colposcopy and loop treatment is a safe and effective option for treatment of cervical epithelial abnormalities. The experience of the colposcopist is very important.

Innervation-independent changes in the mRNAs encoding tyrosine hydroxylase and the norepinephrine transporter in rat adrenal medulla after high-dose reserpine

To determine whether a trans-synaptic mechanism triggered the effects of reserpine on adrenomedullary mRNAs encoding the norepinephrine transporter and tyrosine hydroxylase, we administered 10 mg/kg reserpine to rats after unilateral splanchnicotomy, and examined their adrenal medullas using quantitative in situ hybridization. Splanchnicotomy did not alter the decrease in norepinephrine transporter mRNA that follows reserpine administration, but diminished the reserpine-induced increase in tyrosine hydroxylase mRNA by almost 80%. Despite the latter effect, reserpine still induced a significant increase in tyrosine hydroxylase mRNA in denervated adrenal medullas, compared to vehicle-treated adrenal medullas. These results show that a trans-synaptic mechanism does not trigger the decrease in adrenomedullary norepinephrine transporter mRNA following reserpine. In addition, an innervation-independent mechanism mediates a portion of the reserpine-induced increase in adrenomedullary tyrosine hydroxylase mRNA.

Effect of a herbal compound for treatment of sarcoptic mange infestations on dogs

Charmil gel, a herbal product was tried against Sarcoptes scabei var canis on dogs and its efficacy was compared with that of amitraz. Mite scrapings examined at scheduled intervals after the topical application of Charmil gel caused complete recovery after 14 days in severe infestation and 7 to 10 days in mild to moderate infestations with regrowth of hair on Day 28 post-treatment. No adverse reactions were observed except mild irritation and restlessness, which persisted for a few hours soon after application.

Endocarditis due to high level gentamicin resistant Enterococcus faecium

We describe the first reported case in the literature of bacterial endocarditis caused by Enterococcus faecium that was highly resistant to gentamicin. The case is unusual in that it followed a successfully treated Streptococcus sanguis endocarditis. The micro-organism was susceptible only to the glycopeptide antibiotics, vancomycin and teicoplanin and to agents such as pristinamycin and daptomycin which are not routinely available for treatment. It illustrates the therapeutic dilemma posed by serious infections with such micro-organisms and supports previous observations that early heart valve replacement surgery may be necessary to achieve cure of endocarditis due to enterococci which are highly resistant to gentamicin. It further emphasises the importance of screening for high-level aminoglycoside resistance in enterococci in all life threatening enterococcal infections, including endocarditis, septicaemia and meningitis when aminoglycoside-penicillin synergy is required for successful treatment.

A study of dichotomous thought processes in accident-prone drivers

When a frequency distribution of motor vehicle accidents in any particular group is analysed, there is found to be a number of individuals who have a greater proportion of accidents than can be explained by chance alone. Research on the psychology of accident causation has been aimed largely at isolating particular personality characteristics which seem to be associated with high accident liability. However, the results from past research have been far from encouraging. Very little has been conclusively proved regarding the bearing of any one attribute on the accident rate, and there is still no single specific factor that is psychometrically capable of being identified as a predictor of accident liability.