Effect of continuous microwave processing on enzymes and quality attributes of bael beverage

Bael (Aegle marmelos) beverage was pasteurized using continuous-microwave (MW) and traditional thermal processing and the activity of native enzymes, pulp-hydrolyzing enzymes, bioactive, physicochemical, and sensory properties were analyzed. First-order and linear biphasic models fitted well (R2 ≥ 0.90) for enzyme inactivation and bioactive alteration kinetics, respectively. For the most resistant enzyme, polyphenoloxidase (PPO), the inactivation target of ≥ 90 % was achieved at 90 °C TMW (final temperature under MW) and 95 °C for 5 min (conventional thermal). MW treatment displayed faster enzyme inactivation and better retention of TPC and AOC. MW treatment at 90 °C TMW showed 5.3 min D-value, 90% total carotenoid content, 3.42 crisp sensory score (out of 5), and no or minor change in physicochemical attributes. Thermal and MW treatment caused the loss of 14 and 10 bioactive compounds, respectively. The secondary and tertiary structural modifications of PPO enzyme-protein revealed MW's lethality primarily due to its thermal effects.

Pasteurization of fruit juices by pulsed light treatment: A review on the microbial safety, enzymatic stability, and kinetic approach to process design

Pulsed light (PL) is a polychromatic radiation-based technology, among many other non-thermal processing techniques. The microbiological lethality of the PL technique has been explored in different food matrices along with their associated mechanisms. Pasteurization of fruit juice requires a 5-log cycle reduction in the resistant pathogen in the product. The manufacturers look toward achieving the microbial safety and stability of the juice, while consumers demand high-quality juice. Enzymatic spoilage in fruit juice is also a crucial factor that needs attention. The retailers want the processed juice to be stable, which can be achieved by inactivating the spoilage enzymes and native microflora inside it. The present review argued about the potential of PL technology to produce a microbiologically safe and enzymatically stable fruit juice with a minimal loss in bioactive compounds in the product. Concise information of factors affecting the PL treatment (PLT), primary inactivation mechanism associated with microorganisms, enzymes, the effect of PLT on various quality attributes (microorganisms, spoilage enzymes, bioactive components, sensory properties, color), and shelf life of fruit juices has been put forward. The potential of PL integrated with other non-thermal and mild thermal technologies on the microbial safety and stability of fruit juices has been corroborated. The review also provides suggestions to the readers for designing, modeling, and optimizing the PLT and discusses the use of various primary, secondary kinetic models in detail that have been utilized for different quality parameters in juices. Finally, the challenges and future need associated with PL technology has been summarized.

Assessment of asthma control in users of oral anti-asthma medications

BACKGROUND: Despite guidelines recommending inhalation therapy as the preferred choice, oral therapy is still widely used in the treatment of asthma in India. However, data about the level of asthma control and healthcare use in patients on oral anti-asthma medications are scarce.METHODS: A retrospective study was conducted to assess the level of asthma control and healthcare use in patients taking oral anti-asthma medications.RESULTS: The study population consisted of 381 adults randomly selected from health screening programmes. All subjects were already receiving oral anti-asthma medications; however, up to 72% had not been diagnosed with asthma by their treating doctors prior to the screening programmes. The cohort had a mean age of 48.26 ± 13.83 years (70% males) and mean peak expiratory flow of 245 ± 78.93 mL/sec. The mean Asthma Control Questionnaire 5 (ACQ-5) score was 2.53 ± 1.15, with respectively 33%, 49.3% and 32.6% reporting at least one episode of breathlessness, one emergency doctor visit and one hospitalisation due to asthma or its symptoms in the past year.CONCLUSION: Underdiagnosis and inappropriate management, as indicated by the poor asthma control and increased hospitalisations seen in this study, is probably a key contributor to the increased burden of the disease in India.

COPD exacerbation rates are higher in non-smoker patients in India

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is common among non-smokers exposed to solid fuel combustion at home. Different clinical characteristics in these patients may have significant therapeutic and prognostic implications.METHODS: We used medical record review and a questionnaire among COPD patients at 15 centres across India to capture data on demographic details, different types of exposures and clinical characteristics. Chest radiography and pulmonary function testing were performed in all 1984 cases; C-reactive protein and exhaled breath nitric oxide were measured wherever available.RESULTS: There were 1388 current or ex-smokers and 596 (30.0%) non-smokers who included 259 (43.5%) male and 337 (56.5%) female patients. Sputum production was significantly more common in smokers with COPD (P < 0.05). The frequency of acute symptomatic worsening, emergency visits and hospitalisation were significantly higher (P < 0.05) in non-smokers with COPD; however, intensive care unit admissions were similar in the two groups. There was no significant difference with respect to the use of bronchodilators, inhalational steroids or home nebulisation among smoker and non-smoker patients. The mean predicted forced expiratory volume in 1 sec in smokers (43.1%) was significantly lower than in non-smokers (46.5%).CONCLUSION: Non-smoker COPD, more commonly observed in women exposed to biomass fuels, was characterised by higher rate of exacerbations and higher healthcare resource utilisation.

Formulation of a mixed fruit beverage using fuzzy logic optimization of sensory data and designing its batch thermal pasteurization process

The study aims to formulate a mixed fruit beverage through sensory analysis, and the composition was optimized using a fuzzy logic algorithm. The fuzzy optimization algorithm was developed using a modified Takagi and Sugeno's approach, polynomial mixture modeling, and nonlinear solver engine. The optimized blend consisted of amla juice, pineapple juice, and coconut water in 14.3, 63.0, and 22.7%, respectively. Further, the batch thermal treatment was carried out within 50 to 95 °C for an isothermal holding time of 1 s to 10 min, and pasteurization condition for the beverage was estimated from kinetic modeling. The concept of thermal pulse inactivation due to non-isothermal heat-up-time and cool-down-time has been introduced within the process time calculation. From the kinetic study, polyphenoloxidase enzyme appeared to be the most resistant entity towards inactivation among all the natural microbiota and quality deteriorating enzymes. Pasteurization in terms of achieving a 5D reduction of both aerobic mesophilic and yeast-mold counts was attained over a range of 80 to 95 °C for 10.2 + 1.4 to 3.1 + 2.0 min (1.4 and 2.0 min = heat-up-time + cool-down-time), respectively. The 90% inactivation of both polyphenoloxidase and peroxidase enzymes was obtained over a range of 90 to 95 °C for 12.8 + 1.7 to 8.4 + 2.0 min, respectively. While obtaining both the microbial and enzyme stability at the isothermal condition of 95 °C for 8.4 min, the corresponding retention in ascorbic acid, total phenolics, and antioxidant capacity were observed as 49.7, 63.0, and 61.4%, respectively. PRACTICAL APPLICATION: In this work, the formulation of a fruit blend was optimized through an intelligent optimization technique (fuzzy algorithm) applied to the sensory data set. The approach for calculating thermal processing time or pasteurization condition provides a new dimension with better precision. The thermal treatment condition of 95 °C for 10 min can be used for this mixed beverage to achieve both microbial stability (5-log reduction) and enzyme stability (90% reduction). The presented study can be used as a reference for other similar beverages to achieve a complete process design from basic formulation optimization to thermal (batch-type) processing conditions.

Abstract 3127: To investigate the role of BRAF V600E co-occurring mutations in Langerhans cell histiocytosis (LCH)

a. Introduction :

Langerhans cell histiocytosis (LCH) is an inflammatory myeloid neoplasia caused by alterations of several genes in the MAPKinase pathway. The cell of origin is a white blood cell known as a dendritic cell priviously called as histiocyte characterized by a unique cytoplasmic organelle, the Birbeck granule, and the expression of CD1a and class II major histocompatibility complex molecules . The mutations cause these dendritic cells to attract other white blood cells and cause a “lesion” in any organ of the body. LCH has multi-orgnan involvement affecting skin bones, lymph nodes, brain etc. Systemic symptoms may include fever, bone pain, weight loss, jaundice, diabetes insipidus.

b. Description:

LCH is a rare sporadic, non-hereditary and non-malignant disease with unknown etiology characterized with a clonal proliferation of pathologic cells.Recent discovery of recurrent somatic mutations, BRAFV600E in MAPK pathway genes at critical stages of myeloid hematopoietic differentiation in LCH patients supports redefinition of the disease as a myeloproliferative disorder and provides opportunities to develop novel approaches to diagnosis and therapy. In the present proposal, we intend to analyze the BRAFV600E status along with other co-occurring mutations in a cohort of pediatric LCH patients by DNA sequencing in bone marrow samples or Peripheral Blood. Additionally we approach the above unanswered questions by applying an improved machine learning approach for classification and defining an algorithm for disease into different clusters for immediate clinical implication and to address its clinical heterogeneity.

c. Results :

We screened about 5 LCH patients and performed tageted exome seq to asertain the mutational profile of these patients. Sequencing detected BRAF V600E mutation in 3 of 5 samples for a mutation frequency of 60%. IHC based immunofloroscence shows that the intensity of phospho-MEK and phospho-ERK staining shows no significant alterations samples with mutation in BRAF. We are currently investigating mutations in other members of MAK pathways

d. Conclusion :

BRAF-V600E mutations were detected in few of our LCH patients. Neverless seeing the disease heterogeneity, we expect additionall mutations. More studies are needed to investigate mutations in the MAPK pathways that could efffect the course of disease management.We further plan to integrate the clinical and genomic findings to design a predictive model for the disease outcome.

Citation Format: Subhradip Karmakar, R Dhar, K Purkayastha, R Seth, S Karmakar. To investigate the role of BRAF V600E co-occurring mutations in Langerhans cell histiocytosis (LCH) [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3127.

Outcomes and risk factors of cholecystectomy in high risk patients: A case series

Introduction

Many studies looked at outcomes and risk factors in laparoscopic cholecystectomies in general, including a few studies on risk factors and scoring systems in predicting conversion to open surgery. Little data has been produced on high-risk patients undergoing cholecystectomy. Identifying risk factors in this group could help stratify decision making regarding best management strategies.

The aim of this study was to investigate outcomes of laparoscopic cholecystectomies in patients with ASA 3 and 4.

Methods

Data was collected and collated from a prospectively maintained database of all laparoscopic cholecystectomies performed by 13 general surgeons in a single unit. Case notes were reviewed for all patients with ASA 3 and 4 between 2013 and 2017. Data analysis was performed using R studio v 3.4.

Results

244 cases were reviewed. Common bile duct was dilated in 52 cases (21.31%). Gall bladder wall was thick in 102 (41.8%) of the patients. Surgery was elective in 203 (83.2%) of the patients. ERCP was performed in 41 (16.9%) of the patients prior to surgery. 150 patients (62.2%) stayed for 1 day while 36 (14.9%) stayed for 2 days and the remaining 55 (22.9%) stayed for 3 days or more. Complications occurred in 37 (15.16%) of the patients while 23 (9.43%) of the patients were readmitted. 7 patients (2.87%) returned to theatre and 8 (3.28%) stayed in ITU post-op. Two patients died (0.82%).

Conclusion

Laparoscopic cholecystectomies in higher risk populations are safe. Alternative methods such as cholecystostomy and ERCP may be of benefit in these patients.

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Gallstone disease represents a significant volume of elective and emergency work in the United Kingdom.

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The primary aim of the study was to explore the factors that lead to complications in high risk patients (ASA 3-4).

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Histological gallbladder thickness and emergency surgery were the factors most strongly associated with negative outcomes.

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Age greater than 65 as an independent variable does not lead to an increase in negative outcomes.

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Cholecystectomy is a relatively safe procedure in what is typically considered higher risk patients.

Elucidation of the de Vries behavior in terms of the orientational order parameter, apparent tilt angle, and field-induced tilt angle for smectic liquid crystals by polarized infrared spectroscopy

We report experimental results of the orientational order parameter, the apparent tilt angle, and the field-induced tilt angle for three chiral smectic liquid crystalline materials investigated using infrared (IR) polarized spectroscopy. The common feature in these materials is use of the core 5-methyl-2- pyrimidine benzoate as the central part of the mesogen. This core is terminated by siloxane or carbosilane chains on one of the ends and by the chiral alkoxy chains on the opposite. These compounds exhibit low concomitant layer shrinkage at the smectic A^{*} (SmA^{*}) to smectic C^{*} (SmC^{*}) transition temperature and within the SmC^{*} phase itself. The maximum layer shrinkage in SmC^{*} is observed as ∼1.5%. We calculate the apparent orientational order parameter, S_{app} in the laboratory reference frame from the observed IR absorbance for homeotropic aligned samples, and the true order parameter, S, is calculated using the measured tilt angle and is also interpolated from Iso-SmA^{*} transition temperature closer to SmC^{*} phase. The apparent tilt angle in the SmA^{*} phase calculated from a comparison of order parameters S and S_{app} is found to be significantly large. A low magnitude of S_{app} found for homeotropic aligned samples in the SmA^{*} phase indicates that the order parameter plays a vital role in determining the de Vries characteristics, especially of exhibiting larger apparent tilt angles. Furthermore there is a significant increase in the true order parameter at temperatures close to SmA^{*} to SmC^{*} transition temperature in all three compounds. The planar-aligned samples are used to study the dependence of induced tilt angle on the applied electric field. The generalized Langevin-Debye model given by Shen et al. reasonably fits the experimental data on the field-induced tilt angle. The results show that the dipole moment of the tilt correlated domain in SmA^{*} diverges as temperature is lowered to the SmA^{*}-SmC^{*} transition temperature. The generalized Langevin-Debye model is also found to be extremely effective in confirming some of the conclusions of the de Vries behavior.

Chiral smectic-A and smectic-C phases with de Vries characteristics

Infrared and dielectric spectroscopic techniques are used to investigate the characteristics of two chiral smectics, namely, 1,1,3,3,5,5,5-heptamethyltrisiloxane 1-[4^{'}-(undecyl-1-oxy)-4-biphenyl(S,S)-2-chloro-3-methylpentanoate] (MSi_{3}MR_{11}) and tricarbosilane-hexyloxy-benzoic acid (S)-4'-(1-methyl-hexyloxy)-3'-nitro-biphenyl-4-yl ester (W599). The orientational features and the field dependencies of the apparent tilt angle and the dichroic ratio for homogeneous planar-aligned samples were calculated from the absorbance profiles obtained at different temperatures especially in the smectic-A* phase of these liquid crystals. The dichroic ratios of the C-C phenyl ring stretching vibrations were considered for the determination of the tilt angle at different temperatures and different voltages. The low values of the order parameter obtained with and without an electric field applied across the cell in the Sm-A^{*} phase for both smectics are consistent with the de Vries concept. The generalized Langevin-Debye model introduced in the literature for explaining the electro-optical response has been applied to the results from infrared spectroscopy. The results show that the dipole moment of the tilt-correlated domain diverges as the transition temperature from Sm-A^{*} to Sm-C^{*} is approached. The Debye-Langevin model is found to be extremely effective in confirming some of the conclusions of the de Vries chiral smectics and gives additional results on the order parameter and the dichroic ratio as a function of the field across the cell. Dielectric spectroscopy finds large dipolar fluctuations in the Sm-A^{*} phase for both compounds and again these confirm their de Vries behavior.

Neurologic complications of transplantation

Major neurologic morbidity, such as seizures and encephalopathy, complicates 20-30% of organ and stem cell transplantation procedures. The majority of these disorders occur in the early posttransplant period, but recipients remain at risk for opportunistic infections and other nervous system disorders for many years. These long-term risks may be increasing as acute survival increases, and a greater number of "sicker" patients are exposed to long-term immunosuppression. Drug neurotoxicity accounts for a significant proportion of complications, with posterior reversible leukoencephalopathy syndrome, primarily associated with calcineurin inhibitors (i.e., cyclosporine and tacrolimus), being prominent as a cause of seizures and neurologic deficits. A thorough evaluation of any patient who develops neurologic symptoms after transplantation is mandatory, since reversible and treatable conditions could be found, and important prognostic information can be obtained.

Species spectrum and antifungal susceptibility profile of vaginal isolates of Candida in Kuwait

OBJECTIVE

The study was undertaken to determine the prevalence of vulvovaginal candidiasis (VVC) among patients with vaginitis, frequency of different Candida species, and their susceptibility profile.

PATIENTS AND METHODS

Over six months period, high vaginal swabs were cultured on Sabouraud's dextrose agar and isolates were identified by culture on CHROMagar Candida and Vitek2 yeast identification system or/and API 20C (BioMerieux, France). Antifungal susceptibility of the Candida isolates was determined by E-test against amphotericin B, flucytosine, fluconazole, voriconazole, posaconazole and caspofungin.

RESULTS

One thousand seven hundred and fifty-two women with vaginitis were screened for the prevalence of Candida spp. Vaginal swab cultures of 231 (13.2%) women yielded Candida spp. The isolation rates of different species were as follows: Candida albicans (73.9%), Candida glabrata (19.8%), Candida kefir (1.94%), Candida tropicalis (0.96%), Candida parapsilosis (0.96%), Candida krusei (0.96%), Candida guilliermondii (0.96%), and Saccharomyces cerevisiae (0.52%). All strains of C. albicans and non-C. albicans were susceptible to most of the antifungal agents tested.

CONCLUSION

The high frequency with which C. albicans was recovered and its azole susceptibility support the continued use of azole agents for empirical therapy of uncomplicated VVC. However, a larger controlled study is required to determine the role of non-C. albicans in recurrent VVC.

Adaptation of Saccharomyces cerevisiae to saline stress through laboratory evolution

Most laboratory evolution studies that characterize evolutionary adaptation genomically focus on genetically simple traits that can be altered by one or few mutations. Such traits are important, but they are few compared with complex, polygenic traits influenced by many genes. We know much less about complex traits, and about the changes that occur in the genome and in gene expression during their evolutionary adaptation. Salt stress tolerance is such a trait. It is especially attractive for evolutionary studies, because the physiological response to salt stress is well-characterized on the molecular and transcriptome level. This provides a unique opportunity to compare evolutionary adaptation and physiological adaptation to salt stress. The yeast Saccharomyces cerevisiae is a good model system to study salt stress tolerance, because it contains several highly conserved pathways that mediate the salt stress response. We evolved three replicate lines of yeast under continuous salt (NaCl) stress for 300 generations. All three lines evolved faster growth rate in high salt conditions than their ancestor. In these lines, we studied gene expression changes through microarray analysis and genetic changes through next generation population sequencing. We found two principal kinds of gene expression changes, changes in basal expression (82 genes) and changes in regulation (62 genes). The genes that change their expression involve several well-known physiological stress-response genes, including CTT1, MSN4 and HLR1. Next generation sequencing revealed only one high-frequency single-nucleotide change, in the gene MOT2, that caused increased fitness when introduced into the ancestral strain. Analysis of DNA content per cell revealed ploidy increases in all the three lines. Our observations suggest that evolutionary adaptation of yeast to salt stress is associated with genome size increase and modest expression changes in several genes.

Clinical presentation of adult coeliac disease

The mode of presentation of coeliac disease has been changing to more atypical or silent disease. Few studies described the clinical presentation of adult coeliac disease in Ireland in recent years. We retrospectively collected the clinical data for all patients who had a diagnosis of coeliac disease made in our centre between January 07 and December 08. Forty seven adults, predominantly females (n = 30), had a confirmed diagnosis of coeliac disease made during the study period. In our patient cohort, the presenting symptom was diarrhoea in 19 (40%) patients, while 16 patients (34%) did not have any G.I. symptoms, 10 (21%) presented with anaemia. Females presented at a significantly younger age compared to males, with median ages at diagnosis of 44.5 and 57 years, respectively (p = 0.04). Females also presented more commonly with non G.I. symptoms (p = 0.07). The reasons behind this gender difference need further study.

Characteristics of the collective dielectric relaxation mode of the incommensurate SmC(α)(*) phase

Employing the dielectric relaxation spectroscopy technique, we have observed two different characteristics of the collective relaxation mode of an incommensurate SmC(α)(*) phase. Recent theoretical advances predict two different natures for the dielectric relaxation mode in the SmC(α)(*) phase. Our experimental results confirm two different behaviours of the relaxation mode in different temperature ranges for this phase for one unique compound having an exceptionally wide temperature range (∼9 °C) for the SmC(α)(*) phase.

Surveillance of antibacterial resistance in Staphylococcus aureus isolated in Kuwaiti hospitals

OBJECTIVE

To investigate the prevalence of antibiotic resistance among Staphylococcus aureus isolated in Kuwaiti hospitals.

MATERIALS AND METHODS

S. aureus were isolated and identified following standard microbiological methods. Antibacterial susceptibility test was performed by disk diffusion and the measurement of minimum inhibitory concentration with E-test strips.

RESULTS

A total of 1,846 S. aureus isolates were analyzed from 13 hospitals between 1 March and 30 October 2005. They were isolated from 1,765 (95.6%) inpatients and 81 (4.4%) outpatients. Methicillin resistance was detected in 588 (32.0%) of the isolates. The methicillin-resistant S. aureus (MRSA) consisted of 461 (78%) multiresistant and 127 (22%) nonmultiresistant isolates. The nonmultiresistant MRSA consisted of epidemic MRSA-15 and community-associated MRSA. The community-associated MRSA was detected in all hospitals with MRSA, indicating its establishment in Kuwaiti hospitals. The proportion of isolates resistant to gentamicin, kanamycin, erythromycin, tetracycline, ciprofloxacin, fusidic acid and trimethoprim was higher among MRSA than methicillin-susceptible S. aureus (MSSA) isolates. Twenty-four and 22% of MRSA and MSSA isolates, respectively, expressed reduced susceptibility to vancomycin (minimum inhibitory concentration = 3-4 mg/l).

CONCLUSION

The study revealed the presence of methicillin resistance in 32% of S. aureus isolated in Kuwaiti hospitals and revealed an increase in the number of MRSA and MSSA with reduced susceptibility to vancomycin.

High prevalence and level of resistance to metronidazole, but lack of resistance to other antimicrobials in Helicobacter pylori, isolated from a multiracial population in Kuwait

BACKGROUND

The primary treatment regimen for Helicobacter pylori infection for Kuwaitis does not contain metronidazole, but that for expatriates does. There is also increasing failure of antimicrobial therapy.

AIM

To determine the susceptibility of H. pylori from upper gastrointestinal biopsies of Kuwaitis and non-Kuwaitis to find out if differences existed in the susceptibilities of the isolates from the two different populations.

METHODS

The susceptibilities of 96 H. pylori isolates were tested against metronidazole, amoxicillin, clarithromycin and tetracycline by the E test. The rdxA gene was analysed from selected metronidazole-susceptible and metronidazole-resistant strains to find out polymorphism and the basis of metronidazole resistance.

RESULTS

Approximately, 70% of isolates from both populations were metronidazole resistant with 65% isolates showing high minimum inhibitory concentration values of >256 mug/mL. No resistance to the other three antimicrobials was found. There were novel nonsense and missense mutations with no deletion in the rdxA gene by insertion of mini-IS605.

CONCLUSIONS

The prevalence and level of metronidazole resistance in H. pylori in the two populations was high with no difference, in spite of different treatment regimens. Metronidazole resistance in this transitional country appeared to be independent of prior metronidazole use for treatment of H. pylori infection.

Are rheumatologists' treatment decisions influenced by patients' age?

OBJECTIVES

The objective of this study was to determine whether physicians' treatment preferences are influenced by patients' age.

METHODS

We mailed a survey to a random sample of rheumatologists practicing in the US. The survey included a scenario describing a hypothetical patient with rheumatoid arthritis (RA) on hydroxychloroquine, sulfasalazine and low-dose prednisolone, who presents with active disease during a follow-up appointment. The scenario was formulated in two versions that were identical except for the age of the patient. After reading the scenario, respondents were asked to rate (on a 10 cm numerical rating scale) their recommendations for each of the three options: (i) increasing the dose of prednisolone, (ii) adding a new disease-modifying anti-rheumatic drug (DMARD) and (iii) switching DMARDs. Rheumatologists who rated either adding a new DMARD or switching DMARDs higher than increasing the dose of prednisolone were classified as 'preferring aggressive treatment with DMARDs', while the others were classified as 'NOT preferring aggressive treatment with DMARDs'.

RESULTS

A total of 480 rheumatologists were mailed a questionnaire; 204 responded, giving a response rate of 42.5%. Overall 163 (80%) respondents were classified as preferring aggressive treatment with DMARDs. Rheumatologists responding to this survey were more likely to prefer aggressive DMARD treatment for the young RA patient vs the older RA patient (87 vs 71%, P= 0.007).

CONCLUSIONS

Our findings suggest that rheumatologists' treatment recommendations may be influenced by age. Future educational efforts should increase physician awareness of this possible bias in order to ensure equal service delivery across ages.

Dielectric spectroscopy of a binary mixture of liquid crystals showing wide temperature range twisted grain boundary phase with re-entrant cholesteric phase

There are only few materials, which have shown long temperature range twisted grain boundary (TGB) phases. One such material is the chiral binary mixture of 7OCB and 5* CBB (mole ratio 0.8 and 0.2) which shows unique phase sequence of cholesteric ( N*) , a wide temperature range TGBA (approximately 31 degrees C) and reentrant cholesteric (N*re) phases. In the present work we are reporting the dielectric spectroscopy of the above mixture with a chiral analog of earlier reported nematic (N) , smectic- A (SmA) , and reentrant nematic (Nre) phase sequences [Phys. Rev. A 46, 7733 (1992)] for different conditions of molecular orientations. Two modes of dielectric relaxations have been detected in a homeotropically aligned sample with unusually low relaxation frequencies for one of them. Planar oriented molecules in the TGBA phase show a soft mode of relaxation and support the recently proposed theory for the soft mode relaxation of the TGBA phase [Phys. Rev. E 65, 11701 (2001)]. By applying the dc electric field on planar oriented molecules in the TGBA phase, it has been possible to obtain a helix free homeotropically aligned TGBA phase.

Significance of atypical pathogens among community-acquired pneumonia adult patients admitted to hospital in Kuwait

OBJECTIVES

The aim of this study is to determine the microbial etiology and severity of community-acquired pneumonia (CAP) in Kuwait.

SUBJECTS AND METHODS

The severity of consecutive adult CAP cases admitted to 3 hospitals over a 1-year period was classified according to the Pneumonia Outcome Research Team (PORT) severity index. The microbial etiology was determined using standard methods for bacteria and serological tests for atypical and viral pathogens.

RESULTS

The study population was 124 of the 135 admissions; 63 female, 61 male; mean age 41.3+/-18 years. The severity class distribution was: class I 31%, class II 37%, class III 17%, class IV 13%, and class V 2%. Etiological agents were identified from 44 patients (35%), with one pathogen in 31 (25%), two in 9 (7%), and three or more in 4 (3%). The most common pathogens identified were: Mycoplasma pneumoniae in 14 patients (11%), Legionella pneumophila in 10 (8%), Chlamydia pneumoniae in 8 (6%), influenza B virus in 8 (6%), influenza A virus in 5 (4%), Haemophilus influenzae in 4 (3%), Streptococcus pneumoniae in 3 (2%), Staphylococcus aureus in 3 (2%), gram-negative enterobacteria in 5 (4%), Moraxellacatarrhalis in 2 (2%), and viruses in 4 (3%). The yields from laboratory tests were 48% for paired serology, 20% from adequate sputum sample, and 3% from blood culture.

CONCLUSION

Our study shows that a large percentage of mild CAP cases are admitted to hospitals in Kuwait. Atypical pathogens have a significant role in the etiology of CAP. There is overtreatment of CAP with a combination treatment consisting mainly of third-generation chephalosporins and macrolides.

Consumer research: in search of identity

Although the consumer research field has made great progress over the past 30 years with respect to the scope, quality, and quantity of research, there are still significant disagreements about what consumer research is, what its objectives are, and how it should differ from related disciplines. As a result, the field appears to be rather fragmented and even divided on some fundamental issues. In this review we first examine the original vision for the field and its limitations. In the second section we explore the consequences of the ambiguity about the domain and identity of consumer research and the multidisciplinary influences on the field. In particular, we review key trends and "camps" in consumer research, which represent complementary and, in some cases, conflicting views regarding the main topics of investigation and how research is conducted. This review is based in part on systematic analyses of articles that have been published in the leading consumer research journals over the past 30 years. Finally, in the third section we revisit the question of what might differentiate the field from related disciplines, as well as the role of theory testing, studies of substantive phenomena, and relevance in consumer research.

Increasing mortality due to end-stage liver disease in patients with human immunodeficiency virus infection

Highly active antiretroviral therapy has decreased human immunodeficiency virus (HIV)-associated mortality; other comorbidities, such as chronic liver disease, are assuming greater importance. We retrospectively examined the causes of death of HIV-seropositive patients at our institution in 1991, 1996, and 1998-1999. In 1998-1999, 11 (50%) of 22 deaths were due to end-stage liver disease, compared with 3 (11.5%) of 26 in 1991 and 5 (13.9%) of 36 in 1996 (P=.003). In 1998-1999, 55% of patients had nondetectable plasma HIV RNA levels and/or CD4 cell counts of >200 cells/mm(3) within the year before death. Most of the patients that were tested had detectable antibodies to hepatitis C virus (75% of patients who died in 1991, 57.7% who died in 1996, and 93.8% who died in 1998-1999; P=NS). In 1998-1999, 7 patients (31.8%) discontinued antiretroviral therapy because of hepatotoxicity, compared with 0 in 1991 and 2 (5.6%) in 1996. End-stage liver disease is now the leading cause of death in our hospitalized HIV-seropositive population.

Anopheles gambiae salivary gland proteins as putative targets for blocking transmission of malaria parasites

Anopheles gambiae is the primary vector of human malaria in sub-Saharan Africa. Invasion of Anopheles salivary glands by Plasmodium sporozoites is a necessary step in the transmission of malaria and is likely to be mediated by specific receptor-ligand interactions. We are interested in identifying putative an A. gambiae salivary gland receptor or receptors for sporozoite invasion as a possible target for blocking malaria transmission. By using monoclonal antibodies against female-specific A. gambiae salivary gland proteins, two molecules, one of 29 kDa and one of 100 kDa, were identified and characterized with respect to the age and blood-feeding process of mosquitoes. In an in vivo bioassay, the monoclonal antibody against the 100-kDa protein inhibited Plasmodium yoelii sporozoite invasion of salivary glands >/=75%. These results show that A. gambiae salivary gland proteins are accessible to monoclonal antibodies that inhibit sporozoite invasion of the salivary glands and suggest alternate targets for blocking the transmission of malaria by this most competent of malaria vectors.

Mex67p of Schizosaccharomyces pombe interacts with Rae1p in mediating mRNA export

We identified the Schizosaccharomyces pombe mex67 gene (spmex67) as a multicopy suppressor of rae1-167 nup184-1 synthetic lethality and the rae1-167 ts mutation. spMex67p, a 596-amino-acid-long protein, has considerable sequence similarity to the Saccharomyces cerevisiae Mex67p (scMex67p) and human Tap. In contrast to scMEX67, spmex67 is essential for neither growth nor nuclear export of mRNA. However, an spmex67 null mutation (Deltamex67) is synthetically lethal with the rae1-167 mutation and accumulates poly(A)(+) RNA in the nucleus. We identified a central region (149 to 505 amino acids) within spMex67p that associates with a complex containing Rae1p that complements growth and mRNA export defects of the rae1-167 Deltamex67 synthetic lethality. This region is devoid of RNA-binding, N-terminal nuclear localization, and the C-terminal nuclear pore complex-targeting regions. The (149-505)-green fluorescent protein (GFP) fusion is found diffused throughout the cell. Overexpression of spMex67p inhibits growth and mRNA export and results in the redistribution of the diffused localization of the (149-505)-GFP fusion to the nucleus and the nuclear periphery. These results suggest that spMex67p competes for essential mRNA export factor(s). Finally, we propose that the 149-505 region of spMex67p could act as an accessory factor in Rae1p-dependent transport and that spMex67p participates at various common steps with Rae1p export complexes in promoting the export of mRNA.

The prevalence and clonal diversity of penicillin-resistant Streptococcus pneumoniae in Kuwait

Penicillin-resistant Streptococcus pneumoniae (PRSP) is widespread all over the world, including countries previously free of PRSP. This study was undertaken to determine the prevalence, the common serotypes and the clonality of PRSP isolated over a period of 1 year, from various clinical samples from three major hospitals in Kuwait. Strains were identified by standard methods and their antibiotic susceptibility was determined by the agar dilution method. The clonality of the isolates was determined by repetitive extragenic palindromic sequence polymerase chain reaction (REP-PCR) genomic profiling and pulsed field gel electrophoresis (PFGE). Serotyping was done by Quellung reaction using specific antisera. We found that 55% of the S. pnuemoniae were resistant to penicillin (46% and 9% exhibited intermediate and full resistance, respectively). Nearly 41% were resistant to sulfamethoxazole-trimethoprim, 9% to cefotaxime and ceftriaxone, 15% to amoxycillin-clavulanate, 17% to cefuroxime, 77 % to cefaclor, and 14% to clindamycin. The commonest serotypes among the PRSPs were 6A, 6B, 14, 19F, 23F and nontypable. PFGE and REP-PCR patterns showed a large diversity of genetic clones of the PRSP. Serotypes 6B, 14, 19F and 23F were more clonally related than the others. Our data showed that the prevalence of PRSP was high, the serotypes were diversified and different genetic clones make up the population of circulating PRSP in Kuwait.

Folic acid inhibition of EGFR-mediated proliferation in human colon cancer cell lines

Although accumulating evidence suggests a chemopreventive role for folic acid in colon cancer, the regulation of this process in unknown. We hypothesize that supplemental folic acid exerts its chemopreventive role by inhibiting mucosal hyperproliferation, an event considered to be central to the initiation of carcinogenesis in the gastrointestinal tract. The present investigation examines the effect of supplemental folic acid on proliferation of Caco-2 and HCT-116 colon cancer cell lines. Furthermore, because certain tyrosine kinases, particularly epidermal growth factor receptor (EGFR), play a role in regulating cell proliferation, we also examined the folic acid-induced changes in tyrosine kinase activity and expression of EGFR. In Caco-2 and HCT-116 cells, maintained in RPMI 1640 medium containing 1 microg/ml folic acid, we observed that the supplemental folic acid inhibited proliferation in a dose-dependent manner. Pretreatment of HCT-116 and Caco-2 cell lines with supplemental folic acid (1.25 microg/ml) completely abrogated transforming growth factor-alpha (TGF-alpha)-induced proliferation in both cell lines. Tyrosine kinase activity and the relative concentration of EGFR were markedly diminished in both cell lines following a 24-h exposure to supplemental folic acid. The folic acid-induced inhibition of EGFR tyrosine kinase activity in colon cancer cell lines was also associated with a concomitant reduction in the relative concentration of the 14-kDa membrane-bound precursor form of TGF-alpha. In conclusion, our data suggest that supplemental folic acid is effective in reducing proliferation in two unrelated colon cancer cell lines and that EGFR tyrosine kinase appears to be involved in regulating this process.

Regulation of mRNA export by nutritional status in fission yeast

We have isolated a mutation in nup184(nup184-1) that is synthetically lethal with the mRNA export defective rae1-167 mutation in Schizosaccharomyces pombe. The consequence of the synthetic lethality is a defect in mRNA export. The predicted Nup184p is similar to Nup188p of Saccharomyces cerevisiae, and a Nup184p-GFP fusion localizes to the nuclear periphery in a punctate pattern. The Deltanup184 null mutant is viable and also is synthetically lethal with rae1-167. In a rae1(+) background, both the nup184-1 and Deltanup184 mutations confer sensitivity to growth in nutrient-rich medium (YES) that is accompanied by nuclear poly(A)+ RNA accumulation. Removal of the cAMP-dependent protein kinase, Pka1p, relieved the growth and mRNA export defects of nup184 mutants when grown in nutrient-rich medium. The activation of Pka1p is necessary, but not sufficient, to cause the severe poly(A)+ RNA export defects when nup184 mutant cells are incubated in YES, suggesting nutritional status can also regulate poly(A)+ RNA export. Our results suggest that the regulation of poly(A)+ RNA export by Pka1p kinase appears to be indirect, via a translation-dependent step, but post-translationally in response to YES.

p300/cAMP-responsive element-binding protein interactions with ets-1 and ets-2 in the transcriptional activation of the human stromelysin promoter

In this paper we show that transcription factors Ets-1 and Ets-2 recruit transcription adapter proteins p300 and CBP (cAMP-responsive element-binding protein) during the transcriptional activation of the human stromelysin promoter, which contains palindromic Ets-binding sites. Ets-2 and p300/CBP exist as a complex in vivo. Two regions of p300/CBP between amino acids (a.a.) 328 and 596 and a. a. 1678 and 2370 independently can interact with Ets-1 and Ets-2 in vitro and in vivo. Both these regions of p300/CBP bind to the transactivation domain of Ets-2, whereas the C-terminal region binds only to the DNA binding domain of Ets-2. The N- and the C-terminal regions of CBP (a.a. 1-1097 and 1678-2442, respectively) which lack histone acetylation activity independently are capable of coactivating Ets-2. Other Ets family transcription factors failed to cooperate with p300/CBP in stimulating the stromelysin promoter. The LXXLL sequence, reported to be important in receptor-coactivator interactions, does not appear to play a role in the interaction of Ets-2 with p300/CBP. Previous studies have shown that the stimulation of transcriptional activation activity of Ets-2 requires phosphorylation of threonine 72 by the Ras/mitogen-activated protein kinase signaling pathway. We show that mutation of this site does not affect its capacity to bind to and to cooperate with p300/CBP.

Immunization of mice with DNA-based Pfs25 elicits potent malaria transmission-blocking antibodies

Immunological intervention, in addition to vector control and malaria chemotherapy, will be needed to stop the resurgence of malaria, a disease with a devastating impact on the health of 300 to 500 million people annually. We have pursued a vaccination strategy, based on DNA immunization in mice with genes encoding two antigens present on the sexual stages of Plasmodium falciparum, Pfs25 and Pfg27, to induce biologically important antibodies that can block development of the parasite in the Anopheles mosquito and thus transmission of the disease. DNA encoding Pfs25 when administered by the intramuscular route, either alone or with DNA encoding Pfg27, had the most potent transmission-blocking effects, resulting in up to a 97% decrease in oocyst numbers in mosquito midguts and a 75% decrease in rate of infection. Immunization with DNA encoding a Pfg27-Pfs25 fusion protein was less effective and DNA encoding Pfg27 elicited antibodies in sera that had only modest effects on the infectivity of the parasite. These results show for the first time that DNA vaccination can result in potent transmission-blocking antibodies in mice and suggest that the Pfs25 gene should be included as part of a multicomponent DNA vaccine.

Inhibition of the growth and development of asexual and sexual stages of drug-sensitive and resistant strains of the human malaria parasite Plasmodium falciparum by Neem (Azadirachta indica) fractions

Neem (Azadirachta indica) has been shown to possess anti-malarial activity. In this study we systematically evaluated extracts of neem seeds and purified fractions further enriched in polar or non-polar constituents for their effect on in vitro growth and development of asexual and sexual stages of the human malaria parasite Plasmodium falciparum. Use of synchronized stages of parasites suggested trophozoites/schizonts as the susceptible target stages to various neem extracts. In addition, all the maturation stages of gametocytes were also killed by various neem fractions tested. The anti-plasmodial effect of neem components was also observed on parasites previously shown to be resistant to other anti-malarial drugs, i.e. chloroquine and pyrimethamine suggesting a different mode of action. Neem seed fractions are thus active not only against the parasite stages that cause the clinical infection but also against the stages responsible for continued malaria transmission.

Evaluation and comparison of two immunodiagnostic assays for Helicobacter pylori antibodies with culture results

Several commercially available serological kits have been used as an alternative to endoscopy for the diagnosis of Helicobacter pylori infection. We evaluated the performance of two such kits, Serion H. pylori immunotab kit (Serion, Wurzberg, West Germany) and Pyloragen H. pylori test kit (Hypcor Biomedical Inc., Irvine, CA). Gastric biopsy and serum samples were collected from 345 consecutive dyspeptic patients. The culture and or direct smear of the biopsy was positive for H. pylori in 228 patients (66%), whereas 117 patients (34%) were found to be H. pylori negative. We determined the serological response of the patients using the two kits, both of which are based on the principle of enzyme-linked immunosorbent assay. Comparing the serum immunoglobin G (IgG) and IgA (in a limited number of cases) responses to H. pylori status, the sensitivity, the specificity, positive predictive value, and negative predictive value were calculated. The corresponding data for the different tests were 64%, 79%, 84%, and 56% for Serion IgC, 32%, 94%, 88%, and 52% for Serion IgA, and 88%, 17%, 62%, and 46% for Pyloragen IgG, respectively. We conclude that there is a poor correlation between the presence of H. pylori infection and the antibody response, which could be explained either because of low sensitivities and specificities of the commercial kits used for the measurement of antibodies to H. pylori in the serum or because of poor immunological response in our patients to H. pylori antigens.