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A Curry

Publications and source records attributed to A Curry.

At least 37 records · Page 2Linked to original sources
PubMed2000

Electron microscopy as a tool for identifying new pathogens.

Electron microscopy (EM) is still an important tool for the investigation of infectious diseases, despite the introduction of powerful new methods, mainly involving the polymerase chain reaction. Particularly in the field of parasitic protozoology associated with AIDS, where many new species of human pathogens have been recognized in tissue biopsies, EM remains an essential 'catch-all' diagnostic method. The resolved ultrastructural details of these newly recognized parasites allows a unique insight into the biology of these organisms. The information produced by EM is different, but complementary, to that provided by alternative methods.

AIDS-Related Opportunistic Infections↗
PubMed2000

Histamine and tryptase levels in patients with acute allergic reactions: An emergency department-based study.

BACKGROUND: Emergency department visits for acute allergic reactions are common. Although the diagnosis and classification of these allergic reactions is primarily empiric, it is not always clear whether certain signs and symptoms constitute systemic mediator release syndromes, such as anaphylaxis, and thus may warrant more aggressive therapy or follow-up. OBJECTIVE: We sought to determine associations between various clinical signs and symptoms with both plasma histamine levels and serum tryptase levels in adult patients presenting to an emergency department with acute allergic syndromes. The clinical correlates of raised beta-tryptase levels were also investigated. METHODS: Ninety-seven adult emergency department patients were prospectively studied by using a questionnaire, physical examination, and serum-plasma sampling. Plasma histamine and serum total and beta-tryptase levels were determined. Clinical groupings were compared for mediator levels by using simple and multivariate analysis. RESULTS: Elevated levels of plasma histamine (>10 nmol/L) and serum total tryptase (>15 ng/mL) were observed in 42 and 20 patients, respectively. Detectable beta-tryptase (>/=1 ng/mL) was observed in 23 patients, including 15 of the patients with elevated total tryptase levels. Suspected food allergy incidences and the duration of reaction were similar in patients with increased histamine levels and in patients with increased tryptase levels. Increased total tryptase levels, histamine levels, or both were observed in some patients who did not have airway, cardiovascular, or abdominal signs. Histamine levels correlated better with clinical signs than tryptase levels. Histamine elevations (>10 nmol/L) were observed more frequently in patients characterized by the following clinical signs in univariate analysis: the presence of urticaria, more extensive erythema, abnormal abdominal findings, and wheezing. Total tryptase increases were observed more frequently only in patients with urticaria. Histamine levels correlated with initial heart rates. In multivariate analysis the extent of urticaria was the best single predictor of plasma histamine levels and of either an elevated histamine or tryptase level. Detectable beta-tryptase levels were observed in some patients who had neither elevated total tryptase nor elevated histamine levels. Unlike patients without detectable beta-tryptase levels, patients who had detectable beta-tryptase levels had a significant correlation between total tryptase and histamine levels (P <.05). CONCLUSIONS: Raised histamine and, less commonly, raised tryptase levels are observed in almost 50% of patients presenting to emergency departments with acute allergic reactions. Some cases associated with systemic mediator release do not have classical features of severe anaphylaxis, such as hypotension or tachycardia. The lack of total tryptase elevations in many patients with elevated plasma histamine levels suggests basophil involvement. The clinical utility of beta-tryptase determinations in the evaluation of acute allergic reactions needs further study.

Adult↗
PubMed2000

Improved outcomes in patients with acute allergic syndromes who are treated with combined H1 and H2 antagonists.

STUDY OBJECTIVE: Although the addition of H(2) blockers to H(1) antagonists has been promoted for use in anaphylaxis, there have been no large studies establishing the advantage of this approach in treating acute allergic syndromes. In this study we tested the hypothesis that combined H(1) and H(2) blockage results in improved outcomes in patients treated for acute allergic syndromes compared with treatment with H(1) blockade alone. METHODS: In a randomized, double-blind, placebo-controlled trial, 91 adult patients with acute allergic syndromes were treated with either 50 mg of diphenhydramine and saline solution (control group) or with 50 mg of diphenhydramine and 50 mg of ranitidine (active group). These patients were treated with parenteral administration. Patients were recruited from an emergency department at an urban academic medical center. The primary endpoints were resolution of urticaria, angioedema, or erythema at 2 hours after protocol treatment. Areas of cutaneous involvement, heart rates, blood pressures, respiratory findings, and symptom scores were also assessed at baseline, 1 hour, and 2 hours. RESULTS: There were significantly more patients without urticaria at 2 hours among the patients in the active group compared with those in the control group. Both groups had similar proportions of urticaria at baseline. Logistic regression models to predict resolution of urticaria, which accounted for baseline urticarial involvement, showed odds ratios in favor of the active group treatment. Similar findings were observed when the absence of both urticaria and angioedema was considered as the dependent variable. There was not a significant difference between the 2 groups with regard to the absence of erythema or angioedema (irrespective of the presence of urticaria) at 2 hours. Blood pressure and symptoms did not show differences between the 2 groups over time. Lower heart rates were observed 1 hour after treatment in the active treatment group (mean reduction 10 beats/min) compared with those found in the placebo group (mean reduction 6 beats/min). CONCLUSION: These data show that adding H(2) blockers to H(1) antagonists results in additional improvement of certain cutaneous outcomes for patients presenting with acute allergic syndromes. These findings favor the recommendation for using combined H(1) and H(2) antihistamines in acute allergic syndromes.

Acute Disease↗
PubMed2000

Quality of service in nursing homes.

This paper illustrates the relevance of using the Servqual instrument as a service quality measurement tool in the healthcare context. The expectations and perceptions of nursing home residents and their relatives are compared and contrasted to determine the priorities and satisfaction levels of both groups with respect to the services provided. Some interesting differences emerged between the two respondent groups, which gave more accurate and relevant pointers as to potential areas of future improvement. Because a number of nursing homes were surveyed, it was also possible to ascertain which homes might serve as useful examples of the best practice and which were in need of improvement action. In frail, elderly respondent groups it is not especially easy to elicit views as to quality of service. Servqual, carefully and sympathetically designed and applied, proved appropriate for this task.

Aged↗
PubMed1999

Nosema tyriae n.sp. and Nosema sp., microsporidian parasites of Cinnabar moth Tyria jacobaeae.

Nosema tyriae n.sp. was found in 63% of a population of Cinnabar moth larvae (Tyria jacobaeae). The infection was found in the gut wall, silk glands, and fat body and was probably generalized but appeared to be of low pathogenicity. Merogony and sporogony were by binary fission of diplokaryotic stages. Fresh spores were elongate, slightly pointed at the anterior end, and measured 4.7 x 2.0 microm. Ultrastructural features of special interest were 20-nm tubules connecting the surface of sporonts with host cell cytoplasm and, in the spores, a deeply domed polar sac, polaroplast consisting of closely packed longitudinally arranged membranes and loosely packed horizontally arranged membranes, and 10.5-14 coils of the polar tube in a single rank. The 16S rRNA genes of N. tyriae and Nosema bombycis from silkworms, Bombyx mori, differed by only six nucleotides and N. tyriae spores gave a moderately positive reaction with a monoclonal antibody raised to N. bombycis. N. tyriae was infective to B. mori but was less virulent than N. bombycis. However, no amplification product was obtained by PCR using N. tyriae DNA and primers considered to be specific for N. bombycis. Also, the spores of the two species are of entirely different shapes. A second diplokaryotic microsporidium, Nosema sp., found as a light infection in only one of the larvae had much smaller developmental stages and spores measuring 3.8 x 2.0 microm (fixed). Ultrastructurally it was distinguished by an abundance of dense membranes in cytoplasmic vesicles in both meronts and sporonts. Spores with up to 15 coils of the polar tube in irregular clusters or with about 12 coils in a single rank were observed in the tissues fixed from the one larva infected with this parasite. As this larva had been kept with N. tyriae-infected larvae for a few days before examination, it is possible that the two types of spores resulted from a double infection.

Animals↗
PubMed1999

Ultrastructure of Myxidium trachinorum sp. nov. from the gallbladder of the lesser weever fish Echiichthys vipera.

Myxidium trachinorum sp. nov. is described from the gallbladder of the lesser weever fish Echiichthys vipera. Pseudoplasmodia attach themselves to the gallbladder epithelium by filose processes, which are inserted between host cells. Pseudoplasmodia undergo endogenous cell formation at the secondary and tertiary levels. In the proliferative cycle, primary and endogenous cells are packed with digestive vacuoles formed by phagocytosis. In the sporogonic cycle the pseudoplasmodium becomes a pericyte enclosing two secondary cells (lacking digestive vacuoles) in a vacuole. These give rise to five cells each two valvogenic, two capsulogenic and a binucleate sporoplasm, which mature into spores. Comparison of the disporic M. trachinorum with polysporic species of Myxidium revealed significant differences in plasmodial ultrastructure, especially their attachments to host cells, surface characteristics and mode of nutrition, and in formation of generative cells. These suggest that the genus Myxidium may require revision.

Animals↗
PubMed1999

Rapid improvement of peak flow in asthmatic patients treated with parenteral methylprednisolone in the emergency department: A randomized controlled study.

STUDY OBJECTIVE: Corticosteroids are thought to exert their physiologic effects in asthma over the course of several hours. In this study we tested the hypothesis that intravenous methylprednisolone improves airflow in a shorter time frame (2 hours) in adults with acute asthma. METHODS: In a randomized, double-blind, placebo-controlled trial, 56 adult asthmatic patients with peak expiratory flow rates (PEFRs) less than 50% predicted after an initial albuterol aerosol treatment were studied. These patients were randomly assigned to treatment with either 125 mg of intravenous methylprednisolone or an equivalent volume of normal saline solution (placebo). Patients were also treated with identical schedules of nebulized ipratropium and albuterol. Patients were recruited from an emergency department at an urban academic medical center. The primary endpoints were changes in PEFR and in percent predicted PEFR over time. PEFRs were assessed at baseline and at 1 and 2 hours. Heart rate changes over time and the proportion of admissions in the 2 groups were also compared. RESULTS: The increases in PEFR and percent predicted PEFR over time were both significantly greater in the methylprednisolone treatment group (P =. 002 and P =.005, respectively). The increases in geometric mean peak flow at 60 and 120 minutes were 79 and 96 L/min for the methylprednisolone group and 54 and 68 L/min for the placebo group. There was also a significantly different change in heart rates with time between the methylprednisolone and placebo groups (P =.029), with the placebo group showing a moderate increase in heart rate over time. Although the proportion of patients admitted for status asthmaticus was less in the methylprednisolone treatment group (8/30) compared with the placebo group (10/26), this difference in proportions (-.118, 95% confidence interval -.363 to.127) was not significant. CONCLUSION: These data suggest that use of corticosteroids should be considered relatively early in the treatment of patients with acute asthma in whom initial bronchodilator therapy fails to produce an adequate response.

Adult↗
PubMed1999

Vairimorpha imperfecta n.sp., a microsporidian exhibiting an abortive octosporous sporogony in Plutella xylostella L. (Lepidoptera: Yponomeutidae).

The microsporidian genus Nosema is characterized by development in direct control with host cell cytoplasm, diplokaryotic nuclei throughout development and disporous sporogony. The genus Vairimorpha exhibits the same features plus an octoporous sporogony producing uninucleate spores in a sporophorous vesicle. A microsporidium from diamondback moth, Plutella xylostella, falls between Nosema and Vairimorpha in that it initiates but fails to complete the octosporous sequence in this host. The name Vairimorpha imperfecta n.sp. is proposed. Merogony is mainly by formation of buds from multinucleate meronts, the buds remaining attached in chains. Diplokaryotic spores measure 4.3 x 2.0 microns (fresh) and have 15.5 coils of the polar tube in 1 rank. The octosporous sporogony is aborted owing to irregular formation of nuclear spindles, incomplete cytoplasmic fission and bizarre deposition of electron-dense episporontal secretions. Phylogenetic analyses of the sequences of the small subunit rRNA genes of V. imperfecta and of several Nosema and Vairimorpha spp. place V. imperfecta in a clade with Nosema spp. from Lepidoptera rather than in the clade containing the more typical species of Vairimorpha. It is suggested that the ancestors of the Vairimorpha/Nosema complex of species exhibited both disporous and octosporous sporogonies, as does the type species of Vairimorpha, Vairimorpha necatrix. It would follow that true Nosema spp. have lost the ability to express an octosporous sequence and that V. imperfecta is in the process of losing it. It is proposed that the genera Nosema and Vairimorpha be placed in the same family Nosematidae Labbé 1899, rather than in separate families and orders as at present.

Animals↗
PubMed1999

Human microsporidial infection and possible animal sources.

Sources of human microsporidial infection remain speculative, but possible animal reservoirs are emerging. Of the common human microsporidial infections, Enterocytozoon bieneusi has now been identified in non-human primates, pigs, dogs and a cat; Encephalitozoon intestinalis in dogs, pigs, cows, goats and donkeys and Encephalitozoon hellem in budgerigars and parrots. Evidence of species heterogeneity is also emerging suggesting that some animal isolates may be distinctive. Further molecular epidemiological studies need to be undertaken to clarify which animal genotypes can also infect humans. Some of the less common microsporidial infections found in humans, such as those involving Pleistophora-like species, may be the result of infrequent accidental exposure (for example, inadequately cooked infected fish muscle) and establishment, particularly if the individual is severely immunocompromised.

Journal Article↗
PubMed1999

A rationalised virological electron microscope specimen testing policy. PHLS North West Viral Gastroenteritis and Electron Microscopy Subcommittee.

The aim of this project was to produce guidance for a rationalised virological electron microscopy specimen testing policy for PHLS North West, to facilitate centralisation of a groupwide diagnostic electron microscopy service on a single site. Careful specimen selection to limit numbers and the groupwide use of commercially available enzyme immunoassays has allowed PHLS North West to reduce the number of specimens prepared for electron microscopy. The rationalised virological electron microscopy specimen testing policy has enabled a diagnostic electron microscopy service to be provided from a single site with a manageable workload. Implementation of this specimen testing policy by PHLS North West has been successful and may be applicable to other laboratories (or groups of laboratories) to maximise the use of expensive electron microscopy facilities.

Aged↗
PubMed1999

Intraoperative bacterial contamination in operations for joint replacement.

All surgical operations have the potential for contamination, and the equipment used can harbour bacteria. We collected samples from 100 elective primary hip and knee arthroplasties. These showed rates of contamination of 11.4% for the sucker tips, 14.5% for light handles, 9.4% for skin blades and 3.2% for the inside blades used during surgery; 28.7% of gloves used for preparation were also contaminated. Of the samples taken from the collection bags used during hip arthroplasty, 20% grew bacteria, which represents a significant microbial reservoir. Also, 17% of theatre gowns were contaminated at the end of the operation. Contamination was found in 10% of the needles used during closure of the fascia. Overall, 76% of the organisms grown were coagulase-negative staphylococcus. A total of 63% of operations showed contamination in the field of operation. Some changes in practice are suggested. Follow-up for a minimum of two years revealed one deep infection but the organism was not identified as a contaminant. These data provide a baseline for studying the bacteriology of the surgery of revision arthroplasty.

Arthroplasty, Replacement, Hip↗
PubMed1998

Lactate causes changes in gonococci including increased lipopolysaccharide synthesis during short-term incubation in media containing glucose.

Gonococci (strain BS4(agar)), emerging from lag-phase during 1-1.5 h incubation in a medium containing glucose (28 mM) and either 5 microM or 50 microM sodium lactate, show enhanced capacity for their lipopolysaccharide (LPS) to be sialylated by cytidine 5'-monophospho-N-acetyl neuraminic acid. The sialyltransferase content of the lactate-treated gonococci was not greater than that of control organisms and showed no differences in LPS components. However, the total LPS content of the lactate-treated gonococci was 10-20% higher than that of control organisms, so lactate enhancement may be due to more sialyl receptors becoming available due to an overall stimulation of LPS synthesis. The protein and pentose contents of the lactate-treated gonococci were also higher than those of controls, indicating stimulation of protein synthesis and ribosome production. Electron microscopy showed hair-like external appendages on control but not on lactate-treated gonococci. The above growth conditions are unnatural. However, when concentrations of glucose and lactate were adjusted to values akin to those occurring in vivo (glucose 5 mM alone and with either 1 mM or 10 mM lactate), and gonococcal multiplication occurred during the short incubation period (1-1.5 h), lactate again induced greater contents of LPS, protein and pentose. A high content of LPS, which will contribute to pathogenicity, should be a constant feature of gonococci growing in human urogenital tissues, where lactate is ever present with glucose.

Bacterial Proteins↗
PubMed1998

Evidence for in vivo mitosis by granule-containing mast cells from canine mastocytomas.

Mast cell accumulations are generally considered to arise almost exclusively from the recruitment of non-granulated, bone-marrow-derived, precursor cells, with the stem cell factor (SCF) reported to play a crucial role in the growth, development and maturation of granulated mast cells within specific tissue sites. In this study dog mastocytoma specimens have been examined by both immunohistochemical and ultrastructural techniques, to demonstrate that fully granulated mast cells are capable of mitotic activity. Observations showing the formation of mitotic spindles, chromosome separation and cytokinesis all support the concept that granulated mast cells are capable of proliferative activity. The ability of mature granulated mast cells to replicate provides an alternative process for local increases in mast cell numbers, at least in canine mast cell tumours. Such observations suggest the possibility that normal or neoplastic human mast cells, fully granulated, have the potential to proliferate in specific tissue sites.

Animals↗
PubMed1998

Visceral leishmaniasis (Kala-azar) in two patients with HIV-1 infection: atypical features and response to therapy.

Visceral leishmaniasis (VL) is a well recognized opportunistic infection in patients with HIV-1 infection, which may occasionally present with atypical features. We describe two patients with advanced HIV-1 infection (CD4<100/ mm3) in whom visceral leishmaniasis presented with atypical features, and their response to therapy. Atypical features of visceral leishmaniasis in the two infected patients include absence of fever, dissemination to the duodenal mucosa and to the skin as xanthoma-like lesions. Therapy and secondary prophylaxis remain unsatisfactory, and studies to evaluate combinations of amphotericin B and immunotherapy are needed.

AIDS-Related Opportunistic Infections↗
PubMed1998

Emerging pathogens: Isospora, Cyclospora and microsporidia.

Isospora belli, Cyclospora cayetanensis as well as several species of microsporidia are recognized as emerging protozoan pathogens of humans. All are obligate intracellular parasites, with Isospora and the microsporidia being primarily associated with immunocompromised hosts. Cyclospora is a cause of traveller's diarrhoea, and is responsible for water-borne and food-borne outbreaks of disease. Drug treatment is available for these infections. Improved diagnostic methods including the autofluorescence of I. belli and C. cayetanensis oocysts have assisted in the routine detection of these pathogens. Since the recognition of immunosuppression due to HIV infection, microsporidia have become recognized as important human pathogens with a continuing expansion of the parasite-associated clinico-pathological spectrum. The small size, intracellular nature and poor staining properties with many histological stains result in under-reporting of microsporidial infections. Trichrome stain and optical brighteners are used to detect spores in faeces, urines, respiratory secretions and other aspirates. Electron microscopy remains an important diagnostic method but its sensitivity is relatively poor. Molecular techniques should overcome current diagnostic limitations. The ability to extract DNA and amplify by PCR directly from clinical samples has increased the usefulness of molecular methods. Restriction fragment length polymorphism analysis of amplicons can be used to determine genus, species and strain types of various microsporidia. Increased specificity is required in primer design because current primers used for amplifying non-microsporidian DNA also amplify microsporidian DNA. Diagnosis and pathogen characterisation rely increasingly on PCR-based approaches, and the sequence analysis approach becomes increasingly feasible and affordable. However, robust, reliable and sensitive methods are still required for dissecting pathogenesis, epidemiology, transmission routes and sources of infections.

Animals↗
PubMed1998

Differentiation of desquamative interstitial pneumonia (DIP) from pulmonary adenocarcinoma by immunocytochemistry.

AIM: After a misdiagnosis of pulmonary adenocarcinoma as desquamative interstitial pneumonia (DIP), we investigated whether immunohistochemical markers could differentiate these conditions. METHODS AND RESULTS: Three cases of DIP and one pulmonary adenocarcinoma masquerading as DIP were studied by light and electron microscopy. All cases were mucin-negative. The cases of DIP were CD68 positive but cytokeratin-negative. The adenocarcinoma was cytokeratin-positive (AE1/3 and CAM5.2), as well as showing some CD68-positive cells. Markers for carcinoma (CEA, Ber-EP4, and Leu M1) were negative in all cases. Ultrastructurally the adenocarcinoma appeared to be derived from Type II pneumocytes. CONCLUSION: Before a diagnosis of DIP is made, cytokeratin markers should be used.

Adenocarcinoma↗