Repurposing fusidic acid as an antimicrobial against enterococci with a low probability of resistance development

Drug repurposing constitutes a strategy to combat antimicrobial resistance, by using agents with known safety, pharmacokinetics, and pharmacodynamics. Previous studies have implemented new fusidic acid (FA) front-loading-dose regimens, allowing higher serum levels than those achievable with ordinary doses. As susceptibility breakpoints are affected by serum level, we evaluated the repurposing of FA as an antimicrobial product against enterococci. FA minimum inhibitory concentrations (MICs) against standard enterococci strains; Enterococcus faecalis ATCC 29212 and Enterococcus faecium ATCC 27270 were 2 and 4 µg/mL, respectively. The MIC against 98 enterococcal clinical isolates was ≤ 8 µg/mL; all would be susceptible if categorized according to recalculated breakpoints (≥ 16 µg/mL), based on the serum level achieved using the front-loading regimen. FA administration in vivo, using the BALB/c mouse infection model, significantly reduced bacterial burden by two to three log10 units in the liver and spleen of mice infected with vancomycin-susceptible and -resistant strains. Exposure of the standard enterococcal strains to increasing, but not fixed, FA concentrations resulted in resistant strains (MIC = 128 µg/mL), with thicker cell walls and slower growth rates. Only one mutation (M651I) was detected in the fusA gene of the resistant strain derived from serial passage of E. faecium ATCC 27270, which was retained in the revertant strain after passage in the FA-free medium. In conclusion, FA can be repurposed as an antimicrobial drug against enterococci with a low probability of mutational resistance development, and can be employed for treatment of infections attributable to vancomycin-resistant enterococci.

Compatibility of Al-doped ZnO electron transport layer with various HTLs and absorbers in perovskite solar cells

Perovskite solar cells (PSCs) have shown a significant improvement in cell performance in photovoltaics technology. The commonly used light absorbing material of halide-based perovskite in PSCs has produced high efficiency cells with low cost and a simple fabrication process. However, it contains the harmful substance of Pb, which affects the environment, and the cell still suffers from instability in the long run. Therefore, this work presents a theoretical study of the Pb-free absorber layer of CH₃NH₃SnI₃ that is paired for compatibility with various types of hole transport layers (HTLs). Several key parameters of the absorbent layer and HTL have been optimized to produce the highest power conversion efficiency (PCE) using 1D-SCAPS software under AM 1.5 illumination. It was found that the combination of Cu₂O and CH₃NH₃SnI₃ used as the HTL and absorbent layer, respectively, has resulted in great PCE as high as 27.72%. These findings prove that the use of inorganic HTLs and Pb-free perovskite layers is promising for use in PSCs.

Recent methods for discovering novel bioactive metabolites, specifically antimicrobial agents, from marine-associated microorganisms

Marine microorganisms are a promising source for novel natural compounds with many medical and biotechnological applications. Here we demonstrate limitations and recent strategies for investigating the marine microbial community for novel bioactive metabolites, specifically those of antimicrobial potential. These strategies include culture-dependent methods such as modifying the standard culture media, including changing the gelling agent, dissolving vehicle, media supplementation, and preparation to access a broader range of bacterial diversity from marine samples. Furthermore, we discuss strategies like in situ cultivation, dilution-to-extinction cultivation, and long-term incubation. We are presenting recent applications of culture-independent methods such as genome mining, proteomics profiling, and the application of metagenomics as a novel strategy for structure confirmation in the discovery of the marine microorganism for novel antimicrobial metabolites. We present this review as a simple guide and a helpful resource for those who seek to enter the challenging field of applied marine microbiology.

Exploring the Antivirulence Activity of Pulverulentone A, a Phloroglucinol-Derivative from Callistemon citrinus Leaf Extract, against Multi-Drug Resistant Pseudomonas aeruginosa

(1) Background: Bacterial resistance to antibiotics is a global life-threatening issue. Antivirulence therapy is a promising approach to combat bacterial infections as it disarms the bacteria from their virulence factors with reduced selective pressure and a lower chance of resistance. (2) Methods: Callistemon citrinus leaf extract and its major constituent, Pulverulentone A, were tested for their ability to inhibit biofilm, exopolysaccharides, pyocyanin and proteases produced by MDR P. aeruginosa. In addition, a Galleria mellonella larvae model was employed to evaluate the in vivo cytotoxicity of Pulverulentone A and its ability to combat Pseudomonas infection. Docking study was further performed to investigate Pulverulentone A druggability against main quorum sensing (QS) targets expressed by P. aeruginosa; (3) Results: Both C. citrinus extract and the isolated compound could inhibit biofilm formation, extracellular polymeric substances (EPS) and pigment production by the tested isolates. Unexpectedly, no significant inhibition was observed on proteases production. The in silico docking analysis revealed good interactions of Pulverulentone A with all QS targets examined (LasR, MyfR/PqsR, QscR). Pulverulentone A was safe up to 400 µg·mL⁻¹ in Galleria caterpillars. Moreover, pre-treatment of P. aeruginosa with Pulverulentone A slightly enhanced the survival of the infected larvae. (4) Conclusions: The present study proves Pulverulentone A safety with significant in vitro and in silico antivirulence potential against P. aeruginosa.

Pimenta Oil as A Potential Treatment for Acinetobacter Baumannii Wound Infection: In Vitro and In Vivo Bioassays in Relation to Its Chemical Composition

Bacterial biofilm contributes to antibiotic resistance. Developing antibiofilm agents, more favored from natural origin, is a potential method for treatment of highly virulent multidrug resistant (MDR) bacterial strains; The potential of Pimenta dioica and Pimenta racemosa essential oils (E.Os) antibacterial and antibiofilm activities in relation to their chemical composition, in addition to their ability to treat Acinetobacter baumannii wound infection in mice model were investigated; P. dioica leaf E.O at 0.05 µg·mL⁻¹ efficiently inhibited and eradicated biofilm formed by A. baumannii by 85% and 34%, respectively. Both P. diocia and P. racemosa leaf E.Os showed a bactericidal action against A. baumanii within 6h at 2.08 µg·mL⁻¹. In addition, a significant reduction of A. baumannii microbial load in mice wound infection model was found. Furthermore, gas chromatography mass spectrometry analysis revealed qualitative and quantitative differences among P. racemosa and P. dioica leaf and berry E.Os. Monoterpene hydrocarbons, oxygenated monoterpenes, and phenolics were the major detected classes. β-Myrcene, limonene, 1,8-cineole, and eugenol were the most abundant volatiles. While, sesquiterpenes were found as minor components in Pimenta berries E.O; Our finding suggests the potential antimicrobial activity of Pimenta leaf E.O against MDR A. baumannii wound infections and their underlying mechanism and to be further tested clinically as treatment for MDR A. baumannii infections.

Optimization of β-cyclodextrin consolidated micellar dispersion for promoting the transcorneal permeation of a practically insoluble drug

Development of efficient ocular drug delivery system for antifungal drugs becomes a must nowadays to face and eradicate the widely spread ophthalmic fungal infections. Itraconazole, a triazole antifungal, is struggling to penetrate the cornea and subsequently, its efficacy is limited. The aim of this study was to enhance itraconazole corneal penetration through utilizing the minimum surfactant amount in presence of β-cyclodextrin which acted as a dissolution and permeation enhancer. β-Cyclodextrin consolidated micellar dispersions (CCMD) were prepared after an initial screening to select the composition of surfactant(s). The preparation was done according to a modified melt dispersion technique. The prepared CCMD were characterized through the analysis of their particle size, zeta potential and solubilization efficiency. The optimum formula was chosen based on a factorial response surface analysis and it was composed of 17:1 w/w surfactant/drug, 30:1 w/w cyclodextrin/drug ratios and 0.02% polyethylene oxide. This formula was subjected to in vitro characterization including release, imaging by transmission electron microscope, mucoadhesion, stability, in addition to the determination of the minimum inhibitory concentration. Moreover, the ex vivo/in vivo permeation, safety and efficacy profiles were determined. The optimized CCMD formula was found to be significantly safe, stable, mucoadhesive and efficient to permeate the drug through rabbits' corneas. Consequently, the optimized CCMD formulation can be a promising, safe and efficient platform for the transcorneal delivery of lipophilic drugs including most antifungals.

Accuracy of the Potential Acuity Meter in Predicting the Visual Outcome in Cases of Cataract Associated with Macular Degeneration

In order to ascertain the accuracy and specificity of the Potential Acuity Meter (PAM) in the preoperative evaluation of likely postoperative visual acuity in cases of cataract associated with age-related macular degeneration (ARMD), we studied the results in 130 cases, 54 of whom had preoperatively proved or suspected ARMD associated with a cataract. All of them were operated with extracapsular extraction and implantation of an intraocular lens (IOL), and final visual acuity was established when all the patients were visited three months postoperatively. A positive linear correlation was found between normal ocular fundus and PAM prediction (r = 0.77), and in the group of patients with preoperatively confirmed ARMD (r = 0.77). No difference was found between the preoperative PAM estimation and the final visual acuity in both groups. The PAM prediction was less accurate in cases with doubtful preoperative ARMD (r = 0.58) for whom showed PAM the highest score of false negatives in favor of the final visual acuity. Our results show that PAM is a reliable clinical technique for the prediction of visual results after cataract surgery in cases with preoperatively proved or doubtful macular pathology. To the best of our knowledge, this is the first report regarding the sensitivity and specificity of the PAM in diseased or suspicious maculas associated with cataract.

Remediation of a mixture of analgesics in a stirred-tank photobioreactor using microalgal-bacterial consortium coupled with attempt to valorise the harvested biomass

An artificial microalgal-bacterial consortium was used to remediate a mixture of analgesics (ketoprofen, paracetamol and aspirin) in a stirred-tank photobioreactor. A hydraulic retention time (HRT) of 3days supported poor treatment because of the formation of p-aminophenol (paracetamol toxic metabolite). Increasing the HRT to 4days enhanced the bioremediation efficiency. After applying an acclimatization regime, 95% removal of the analgesics mixture, p-aminophenol and COD reduction were achieved. However, shortening the HRT again to 3days neither improved the COD reduction nor ketoprofen removal. Applying continuous illumination achieved the best analgesics removal results. The harvested biomass contained 50% protein, which included almost all essential amino acids. The detected fatty acid profile suggested the harvested biomass to be a good biodiesel-producing candidate. The water-extractable fraction possessed the highest phenolic content and antioxidant capacity. These findings suggest the whole process to be an integrated eco-friendly and cost-efficient strategy for remediating pharmaceutical wastewater.

On the spectroscopic analyses of 3-(4-Hydroxy-1-methyl-2-oxo-1,2-dihydro-quinolin-3-yl)-2-nitro-3-oxo-propionic acid (HMQNP)

In the present work, a combined experimental and theoretical study on molecular structure and vibrational frequencies of HMQNP were reported. The FT-IR spectrum of HMQNP is recorded in the solid phase. The equilibrium geometries, harmonic vibrational frequencies, thermo-chemical parameters, total dipole moment, nuclear repulsion energy and HOMO-LUMO energies are calculated by DFT/B3LYP utilizing 6-311G(d,p) basis set. Results showed that HMQNP possesses a high dipole moment value of 9.3 Debye. HMQNP spin is doublet state which enhances frontier molecular orbitals to split into alpha (spin ↑) and beta (spin ↓) molecular orbitals with two different energy gaps 4.2 and 2.7 eV, respectively. HMQNP is highly recommended to be a more promising structure for many applications in optoelectronic devices such as solar cells.

Detection of cytogenetics abnormalities in chronic lymphocytic leukemia using FISH technique and their prognostic impact

INTRODUCTION

Chronic lymphocytic leukemia (CLL) is a clonal lymphoproliferative disorder characterized by progressive accumulation of morphologically and immunophenotypically mature lymphocytes. Characterization of genomic aberrations may help to understand the pathogenesis of CLL and may give prognostic information independent from conventional clinical markers for a risk-adapted management of CLL patients.

AIM

The aim of the present study is to determine the most common cytogenetics abnormalities between patients with CLL and its prognostic impact.

PATIENTS AND METHODS

The present study was carried out on 20 adult patients presented with chronic lymphocytic leukemia. The patients were diagnosed on the basis of standard clinical (lymph node involvement and/or hepatosplenomegaly), hematological and immunophenotypic criteria for diagnosis of B-CLL. All cases were studied at the time of their diagnosis. FISH technique was successfully performed on PB samples using CLL LSI probes for ATM (11q22) / GLI (12q13) and 13q14/ p53 (17p13).

RESULTS

For comparative statistical studies, the patients were divided into group I (patients with favorable outcome) and group II (patients with unfavorable outcome). All patients showed one or more cytogenetic abnormality with the prevalence of p53 in 16 patients out of 20 that perfectly correlated with the poor outcome of the patients. This is followed by deletion in the 13q14 and to a lesser extent deletion in ATM gene, but no one has exhibited amplification in the 12q13 locus.

CONCLUSION

p53 deletion as a sole abnormality has a higher prognostic power than other cytogenetics abnormalities. The cytogenetics study using FISH panel for CLL patients in a complementary fashion to the other clinical and laboratory findings may overcome the pitfalls in the diagnosis and may also assess the assignment of therapeutic protocols for CLL patients according to the results of their cytogenetic analysis at the time of diagnosis.

KEYWORDS

FISH, chronic lymphocytic leukemia, CLL, p53, cytogenetics, Egypt.

Closed kinetic chain exercises with or without additional hip strengthening exercises in management of patellofemoral pain syndrome: a randomized controlled trial

BACKGROUND

Patellofemoral pain syndrome (PFPS) is a common musculoskeletal pain condition, especially in females. Decreased hip muscle strength has been implicated as a contributing factor. Isolated open kinetic chain hip abductors and lateral rotators exercises were added by many authors to the rehabilitation program. However, Closed Kinetic Chain (CKC) exercises focusing on hip and knee muscles were not investigated if they can produce similar effect of hip strengthening and decreasing pain without the need of isolated exercises for hip musculature.

AIM

The aim of the present study was to determine the effect of a CKC exercises program with or without additional hip strengthening exercises on pain and hip abductors and lateral rotators peak torque.

DESIGN

Prospective randomized clinical trial.

SETTING

Patients with patellofemoral pain syndrome referred to the outpatient physical therapy clinic of the faculty of physical therapy, cairo university.

POPULATION

Thirty two patients who had patellofemoral pain syndrome with age ranged from eighteen to thirty years.

METHODS

Patients were randomly assigned into two groups: CKC group and CKC with hip muscles strengthening exercises as a control (CO) group. Treatment was given 3 times/week, for 6 weeks. Patients were evaluated pre- and post-treatment for their pain severity using VAS, function of knee joint using Kujala questionnaire, hip abductors and external rotators concentric/eccentric peak torque.

RESULTS

There were significant improvements in pain, function and hip muscles peak torque in both groups (P<0.05). However, there was no statistically significant difference between groups in hip muscles torque (P<0.05) but pain and function improvements were significantly greater in the CO group (P<0.05).

CONCLUSION

Six weeks CKC program focusing on knee and hip strengthening has similar effect in improving hip muscles torque in patients with PFPS as a CKC exercises with additional hip strengthening exercises. However, adding isolated hip strengthening exercises has the advantage of more pain relief.

CLINICAL REHABILITATION IMPACT

CKC exercises with additional hip strengthening could be more beneficial in decreasing pain in PFPS than CKC exercises alone.

FT-IR spectroscopic analyses of 4-hydroxy-1-methyl-3-[2-nitro-2-oxoacetyl-2(1H)quinolinone (HMNOQ)

In the present work, a combined experimental and theoretical study on molecular structure and vibrational frequencies of 4-hydroxy-1-methyl-3-[2-nitro-2-oxoacetyl-2(1H)quinolinone (HMNOQ) was reported. The FT-IR spectrum of HMNCQ is recorded in the solid phase. The equilibrium geometries, harmonic vibrational frequencies, thermo-chemical parameters, total dipole moment and HOMO-LUMO energies are calculated by density functional theory DFT/B3LYP utilizing 6-311G(d,p) basis set. Results showed that HMNOQ is highly recommended to be a promising structure for many applications in optoelectronic devices due to its high calculated dipole moment value (9 Debye) which indicates its high reactivity to interact with the surrounding molecules. The HOMO-LUMO energy gap of HMNOQ is 4 eV.

Socio–economic and behavioural factors affecting the prevalence ofAscarisinfection in a low-country tea plantation in Sri Lanka

The identification of the factors that affect the prevalences of geohelminthiases should help to maximize the effectiveness of programmes for the control of these diseases. In the present study, the relationships between the prevalence and intensity of human infection with Ascaris and the availability of sanitary facilities, socio-economic status and personal health habits have been explored in Sri Lanka. The 176 subjects, who lived on a low-country tea plantation, were aged 2-50 years (median = 13 years) and were investigated between the July and December of 2000. When the prevalence and intensity of Ascaris infection were determined, using Kato-Katz smears, 50.0% of the subjects were found to be secreting the eggs of the parasite. Almost all (96.6%) of the subjects lived in terraces of one-room houses built by the plantation owners, and only 30.7% had access to a latrine. Most (90.3%) obtained their drinking water from common taps, and 48.8% boiled their drinking water. The subjects who only drank water that had been boiled and those who washed their hands before meals were relatively unlikely to be infected (P < 0.05 for each). In congested living conditions with poor sanitary facilities, the level of faecal contamination of the environment is invariably high. Even under these conditions, however, good hygiene and the boiling of all drinking water can reduce the risks of Ascaris infection. In the study setting and in similar environments, regular anthelmintic therapy, improvements in housing conditions and sanitary facilities, and health education, to promote risk-reducing patterns of behaviour, would all be beneficial.

Growth advantage of CD34+ cells in trisomy 8 high-risk myelodysplastic syndrome despite enhanced apoptotic signals

This study examined haematopoietic stem cells of 19 high-risk cases of myelodysplastic syndrome (MDS) for apoptotic and anti-apoptotic signals and cellular proliferation and correlated these with clinical and cytogenetic subtypes, particularly trisomy 8. The aim was to identify cellular and cytogenetic markers of prognostic relevance to survival of high-risk MDS cases. High-risk MDS cases had a significantly higher percentage of apoptotic CD34+ cells and anti-apoptotic survivin+ cells than controls, particularly for trisomy 8 cases. Trisomy 8+ cells showed a significant positive correlation with apoptotic CD34+ cells and capacity for colony formation. The latter was significantly lower in trisomy-8-negative cases than normal controls, while that oftrisomy 8 cases was comparable to controls. Our results suggest that although trisomy 8 cells are in a pro-apoptotic state, they are checked by the enhanced expression of anti-apoptotic signals which provide them with their proliferative advantage.

Disposition kinetics of doxycycline in chickens naturally infected with Mycoplasma gallisepticum

1. The pharmacokinetic properties of doxycycline were determined in healthy chickens and chickens naturally infected with Mycoplasma gallisepticum after a single intravenous (i.v.) and oral administration of the drug at 20 mg/kg body weight. Tissue residues of the tested drug after an oral dose of 20 mg/kg given twice daily for 5 consecutive days were also estimated in diseased chickens. 2. The plasma concentrations of doxycycline following single i.v. and oral administration were higher in healthy chickens than in diseased ones. Following i.v. injection, the elimination half-life (t1/2beta), distribution half-life and mean residence time (MRT) were longer in healthy chickens than in diseased birds. The values of total body clearance (ClB) and volume of distribution (Vdss) were larger in healthy chickens than in diseased birds. 3. After single oral administration, the absorption half-life (tl/2ab) and the elimination half-life were longer in normal birds than in diseased ones. The maximum plasma concentration of the drug was higher in normal chickens than in diseased ones. 4. Following repeated oral administration, the concentration of doxycycline in all tissues except muscle was higher than the corresponding concentrations in plasma. Concentrations of doxycycline in different tissues were in the following order: kidney > liver > lung > muscle. The drug was detected in liver and kidney in substantial concentrations on d 5 post administration of the last dose whereas, on d 7, its concentration in all tissues was below the lower limit of the sensitivity of the assay method used. Because of the low sensitivity of the microbiological assay method used in this study, a safe withdrawal time for doxycycline in diseased birds could not be estimated for the meanwhile.

Prognostic value of daily cardiac surgery score (CASUS) and its derivatives in cardiac surgery patients

BACKGROUND

We aimed to validate the usefulness of CASUS derivatives for cardiac surgery patients and their reliability for daily decision making.

METHODS

We included, prospectively, the data of all adult cardiac surgery patients who had an ICU stay of at least 12 hours between 20 January 2003 and 14 October 2005 in the Department of Cardiothoracic Surgery of the University of Cologne, Germany. Data were collected until ICU discharge and included initial, maximum, mean, and total CASUS values. δ CASUS (difference from initial value) was calculated at 48 and 96 hours postoperatively. The predictive efficacy of the derivatives was tested with calibration and discrimination statistics.

RESULTS

2372 patients were included with a mean age of 66.2 ± 11.2 years. ICU mortality was 3.6 % (n =85). Mean ICU stay was 3.0 ± 6.1 days. The discrimination was very good for all derivatives (area under the curve ranged between 0.988 and 0.926). The calibration was also good except for the total CASUS, which showed a significant difference between the expected and observed mortality. Increased δ CASUS at 48 hours (1038 patients) and 96 hours (435 patients) correlated with an increase in mortality (23.1 % and 42.9 %, respectively), and conversely a decreased mortality rate was observed with decreasing values (1.9 % and 3.8 %, respectively).

CONCLUSION

CASUS derivatives including δ CASUS have a good prognostic value for cardiac surgery patients with regard to the prediction of mortality and survival during ICU stay, with the exception of total CASUS which was not informative.

Anthelmintic prescribing patterns of a sample of general practitioners from selected areas in the Colombo district of Sri Lanka

General Practitioners (GPs) provide first contact care of children and pregnant mothers in the community. This study ascertained the prescribing pattern of anthelmintics to children and pregnant women by a sample of GPs from the district of Colombo. Two hundred medical practitioners engaged in full-time General Practice (100 urban and 100 rural), were selected randomly. A pre-tested interviewer-administered questionnaire was used to collect data. A total of 183 GPs aged between 26 and 72 years (median 38) participated with 94 coming from urban areas. Seventy percent of the GPs were male. Almost 13% of GPs from urban areas had a Postgraduate degree in comparison to 4.5% from the rural areas (P < 0.05). Over 50% of GPs had 6-20 years of service and over 30% treated 16-30 patients daily. Seventy-three percent of GPs from rural areas accessed health-related reading material either daily or weekly in contrast to only 40% from urban areas (P < 0.001). All GPs prescribed anthelmintics to children. Pyrantel pamoate was the preferred anthelmintic used for children by both groups. Approximately 55% and 64% of GPs from urban and rural areas, respectively, prescribed anthelmintics during pregnancy. A majority of GPs prescribed drugs after the first trimester. However, 25% from urban areas gave drugs during any trimester (P < 0.001). Regression analysis revealed that GPs with postgraduate qualifications, those having frequent access to health-related material and those seeing more than 30 patients daily, prescribed anthelmintics to pregnant women more often. Although routine de-worming of pregnant women and children should occur through government antenatal and well-baby clinics, and through the schools de-worming programme, it may not happen due to various reasons. Thus, GPs play a vital role in achieving good coverage of anthelmintics among children and pregnant women. Making available clear national guidelines on prescribing anthelmintics in Sri Lanka would improve the prescribing patterns of anthelmintics among GPs.

Impact of the 2004 mass drug administration for the control of lymphatic filariasis, in urban and rural areas of the Western province of Sri Lanka

Lymphatic filariasis is targeted to be eliminated globally, at least as a public-health problem, by 2020. The comprehensive strategy for achieving this goal includes the interruption of the transmission of the causative parasites, by drastically reducing the prevalences of microfilaraemia in at-risk communities. In a descriptive, comparative, cross-sectional and community-based study, the impact of the 2004 mass drug administration (MDA) on filarial infection, in selected areas of the Western province of Sri Lanka, has now been assessed 1-2 and 11 months after the administration of the diethylcarbamazine-albendazole combination employed. Using the cluster-sampling method, urban study populations were selected in the Colombo districts and rural ones were selected in the Gampaha district. After obtaining informed written consent, 2 ml venous blood were collected, between 20.00 and 24.00 hours, from each subject. Personal details and drug compliance in the 2004 MDA were recorded. The samples of 'night' blood were checked for microfilariae, using membrane filtration, and for filarial antigenaemia, using commercial (NOW) immunochromatographic test kits. Eighty-four (4.10%) of the 2034 subjects examined 1-2 months after the 2004 MDA but only four (0.20%) of the 1974 subjects checked 11 months after the MDA were found antigenaemic and/or microfilaraemic (P<0.001). Between the two follow-ups, the overall prevalences of both antigenaemia (4.03% v. 0.15%; P<0.001) and microfilaraemia (0.20% v. 0.05%; P=0.38) fell, although only the reduction in antigenaemia was statistically significant. The prevalence of infection (as indicated by antigenaemia and/or microfilaraemia) fell significantly within each of the two study districts (P<0.001). Although, when the prevalence of infection was high, drug compliance appeared to be an important determinant of the reduction of antigenaemia (P=0.04), the 20% difference in compliance between urban and rural areas had no apparent effect on the corresponding prevalences of infection recorded at either follow-up.

Immunodiagnosis of bancroftian filariasis

The development of immunodiagnostic tests (IDTs) for bancroftian filariasis must be aimed at defined objectives, such as the determination of exposure rates, the detection of microfilaraemia and the diagnosis of clinical filariasis. Assays for both antibody and antigen detection are necessary. Antigen determination may be more appropriate in the detection of microfilaraemia, but for clinical filariasis, antibody determination may prove more useful. The microfilarial surface antigens are very good candidates for this purpose. Determination of antibody to larval antigens may be the best way of establishing exposure rates for epidemiological purposes. An important prerequisite for IDT development is the characterization of antigens at epitope level. Sharing of antigen epitopes with host antigens could be a major limitation in IDT development. An understanding of the parasitological and immunological background of the endemic locality is also necessary. It is recommended that all IDTs are evaluated in follow-up case studies.

Synthesis and evaluation of 2,6-piperidinedione derivatives as potentially novel compounds with analgesic and other CNS activities

New 2,6-piperidinediones 2(a-g) and 4(a-d) were prepared by initial condensation of aromatic aldehydes or cycloalkanones with cyanoacetamide to give alpha-cyanocinnamides l(a-g) or cycloalkylidenes 3(a,b) which underwent Michae1 addition with ethyl cyanoacetate or diethylmalonate. Compounds 4(a-d) were alkylated by various alkyl halides to produce the N-alkylated 2,6-piperidinedione derivatives 5(a-m). Some new selected compounds 2(a-c,f), 4(a-d) and 5(e,h,j) were pharmacologically evaluated for potential anticonvulsant, sedative and analgesic activities. These compounds exhibited significant anticonvulsant and analgesic effects after a single I.P. administration 100 mg/kg b.wt. On the other hand all the investigated compounds induced hypnotic activity and prolonged the phenobarbital sodium- induced sleep as compared with the control group and the most potent compound was found to be 2(f).

Effects of climatic, socio-economic and behavioural factors on the transmission of hookworm (Necator americanus) on two low-country plantations in Sri Lanka

The climatic, socio-economic and behavioural factors influencing hookworm (Necator americanus) infection in Sri Lanka were explored between February 2000 and June 2001. In February 2000, a single stool sample was collected from each of the 477 subjects investigated, who were aged 2-74 years (median = 13 years) and lived on the 'lowcountry' Maliboda and Ayr plantations. The 'baseline' prevalence (28.5%) and intensity of hookworm infection (0- 4828.5 eggs/g faeces, with a mean of 128.4 eggs/g) were then determined by examining these initial samples, as Kato-Katz smears. Subsequently, each participant was treated with a single, 500-mg dose of mebendazole and then followed-up, at monthly intervals, for the next 15 months. Whenever a subject was found smear-positive for hookworm eggs at one of the monthly follow-ups, he or she was treated again with mebendazole. This approach allowed the monthly incidence of hookworm infection to be determined for each subject, assuming that subjects became smear-positive approximately 6 weeks post-infection. During the study period, rainfall and mean temperature were recorded daily and then converted to monthly values so that the relationship between the incidence of infection over each month and the rainfall and mean temperature over the same period could be explored. In addition, potentially relevant data on the socio-economic status and behaviour of each subject were collected, in questionnaire-based interviews with the adult subjects and the caregivers of the children investigated. Odds ratios (OR) and their 95% confidence intervals (CI) were then calculated for each factor that might increase the risk of hookworm infection. The monthly incidence of hookworm infection showed three peaks -- in September 2000 (21.3%), January 2001 (20.8%) and May 2001 (17.5%) -- at Maliboda, and two peaks -- in September 2000 (25.0%) and February 2001 (29.2%) -- at Ayr. With the data for all subjects combined, incidence showed a statistically significant correlation with mean temperature (r = -0.468; P = 0.018). The results of a multivariate analysis also revealed that mean temperature was significant (beta = -5.296; P = 0.01) in hookworm incidence. Bathing and washing with water from rock-pools formed by waterfalls (OR = 1.33; CI = 1.35-4.01), the use of wells (OR = 2.35; CI = 1.29-4.30), and a lack of toilets (OR = 1.60; CI = 1.01-2.53) each appeared to increase the risk of hookworm infection significantly. Those living on the two study plantations, and perhaps many other similar plantations in Sri Lanka, would clearly benefit from improved access to the public water supply (especially to pipe-borne water) and toilets.

Development of antigen-capture enzyme-linked immunosorbent assay and RT-PCR for detection of turkey astroviruses

Turkey astrovirus (TAstV) is an important agent of poult enteritis. The diagnosis of astroviruses has been dependent mainly on electron microscopy (EM) or immune EM (IEM). To develop other simple, rapid, and reliable diagnostic assays, two antigen-capture enzyme-linked immunosorbent assays (AC-ELISAs), polyclonal AC-ELISA and monoclonal AC-ELISA, were developed in this study. Monoplex and multiplex reverse transcription-polymerase chain reactions (RT-PCRs) were also developed using nondegenerate primer sets specific to the capsid region and degenerate primer pairs specific to the polymerase area of two TAstV. EM was included for comparison. Fecal or intestinal contents samples from naturally and experimentally infected poults with enteritis were examined using the developed assays. The polyclonal AC-ELISA had higher sensitivity and wider detection spectrum than the monoclonal AC-ELISA with group-specific monoclonal antibody (MAb), whereas the monoclonal AC-ELISA had very high specificity but lower sensitivity, which was estimated at 0.06 microg of viral proteins. Small round viruses (SRV) that could be astroviruses or other small viruses were detected in 34.4% of the samples examined by EM. The monoplex RT-PCR results amplified with primers SRV-1-3 and SRV-1-5 revealed that the positive rate of astroviruses was 45.3%, which was 10.9% higher than that of EM even if other SRVs were not excluded. Multiplex RT-PCR with SRV-1-3 and SRV-1-5 and AFCP-F1 and AFCP-R1 and the monoplex RT-PCR with degenerate primers verified that the positive rate of astroviruses was 59.4%, which was 25% higher than that of EM. Both RT-PCRs showed good specificity and wider detection spectrum compared with earlier published data.

Pharmacokinetics, Urinary and Mammary Excretion of Ceftriaxone in Lactating Goats

The pharmacokinetic properties of ceftriaxone were investigated in 10 goats following a single intravenous (i.v.) and intramuscular (i.m.) administration of 20 mg kg(-1) body weight. After i.v. injection, ceftriaxone serum concentration-time curves were characteristic of a two-compartment open model. The distribution and elimination half-lives (t(1/2alpha), t(1/2beta)) were 0.12 and 1.44 h respectively. Following i.m. injection, peak serum concentration (C(max)) of 23.6 microg ml(-1) was attained at 0.70 h. The absorption and elimination half-lives (t(1/2ab), t(1/2el)) were 0.138 and 1.65 h respectively. The systemic bioavailability of the i.m. administration (F %) was 85%. Following i.v. and i.m. administration, the drug was excreted in high concentrations in urine for 24 h post-administration. The drug was detected at low concentrations in milk of lactating goats. A recommended dosage of 20 mg kg(-1) injected i.m. every 12 h could be expected to provide a therapeutic serum concentration exceeding the minimal inhibitory concentrations for different susceptible pathogens.

Disposition kinetics, bioavailability and renal clearance of cefepime in calves

The pharmacokinetics of cefepime were studied following intravenous and intramuscular administration of 6.5 mg/kg in four female Friesian calves. Following single intravenous administration, the serum concentration-time curves of cefepime were best fitted using a two-compartment open model. The elimination half-life (t(1/2)beta) was 2.38+/-0.16 h, volume of distribution at steady state (Vdss) was 0.21 +/- 0.01 L/kg, and total body clearance (ClB) was 1.1 +/- 0.08 ml/min per kg. Following intramuscular administration, the drug was rapidly absorbed with an absorption half-life (t(1/2)ab) of 0.29+/-0.02 h; maximum serum concentration (Cmax) of 21.7 +/- 1.1 microg/ml was attained after (Tmax) 1.1 +/- 0.08 h; and the drug was eliminated with an elimination half-life (t(1/2)el) of 3.02 +/- 0.18 h. The systemic bioavailability (F) after intramuscular administration of cefepime in calves was 95.7% +/- 7.44%. The in vitro serum protein-binding tendency was 10.5-16.7%. Following administration by both routes, the drug was excreted in high concentrations in urine for 24 h post administration.

Wet-days: are they better indicators of Ascaris infection levels?

Seasonal variation in a particular area may influence the occurrence of helminth infections and determining such fluctuations may help to maximize the beneficial effects of mass treatment. This study determined the seasonal variations in infection levels of Ascaris lumbricoides between March 2000 and June 2001 in two selected low-country plantations. Four hundred and seventy seven persons aged between 2 and 74 years (median 13) participated. Stools were tested using the Kato-Katz method and the prevalence and intensity of infection determined. All persons were treated with a single dose of mebendazole. Monthly follow-ups were undertaken with similar stool examinations and treatment given if found positive. Infection and re-infection rates were calculated each month. Rainfall and temperature were recorded each day. Total rainfall, number of wet-days and mean temperature was calculated for each month. The prevalence of Ascaris infection was 53.4% and 51.0% at Maliboda and Ayr estates respectively. Highest infection and re-infection rates at Maliboda (37.7%, 37.2%) occurred in June and at Ayr (13.3%, 25.9%) in October 2000 respectively. During the study period, the mean rainfall was 28.1 cm (range 7.4-63.9 cm) and mean temperature 27.6 degrees C (range 22.1 degrees -34.4 degrees C). Significant correlations (P<0.05) were found between the re-infection rate and rainfall, temperature and the number of wet-days. Similar correlations were observed with the infection rate and temperature and the number of wet-days. Ascaris infections were found to correlate significantly only with the number of wet-days in a month (P<0.01). Thus, the number of wet-days appears to be a better indicator of Ascaris infections than total rainfall or mean temperature.

Pathogenicity of turkey coronavirus in turkeys and chickens

We designed this study to compare the replication potential of turkey coronavirus (TCV) and its effect in chickens and turkeys and to study the effect of singleand combined infection of turkey poults with TCV and astrovirus. We studied the pathogenicity of TCV in experimentally inoculated turkey poults and chickens by observing the dinical signs and gross lesions. Two trials were conducted with 1-day-old and 4-wk-old specific-pathogen-free turkey poults and chickens. One-day-old turkey poults developed diarrhea at 48 hr postinoculation. Poults euthanatized at 3, 5, and 7 days postinoculation had flaccid, pale, and thin-walled intestines with watery contents. The 4-wk-old turkeys had no clinical signs or gross lesions. One-day-old and 4-wk-old chicks developed no clinical signs or gross lesions although the TCV was detected in gut contents of the birds throughout the experimental period (14 days). In another experiment, mean plasma D-xylose concentrations in 3-day-old turkey poults inoculated with TCV, turkey astrovirus, or a combination of both viruses were significantly lower than in the uninoculated controls.

Antigenic and genomic relatedness of turkey-origin coronaviruses, bovine coronaviruses, and infectious bronchitis virus of chickens

In earlier studies in our laboratory, we found that bovine coronavirus (BCV) was pathogenic for 1-day-old turkey poults. This finding prompted us to study the antigenic and genomic relatedness of turkey origin coronaviruses (TOCVs) to BCV. A one-step reverse transcription (RT)-polymerase chain reaction (PCR) targeting a 730-base pair fragment of the nucleocapsid (N) gene of BCV and a nested PCR targeting a 407-base pair fragment of the N gene were used in an attempt to detect TOCV from North Carolina, Indiana, and a prototype turkey coronavirus (TCV) obtained from the American Type Culture Collection. Both the one-step RT-PCR and the nested PCR amplified cell culture-passaged isolates of calf diarrhea strains of BCV but none of the 15 tested TOCVs or transmissible gastroenteritis coronavirus of swine. TOCVs also did not cross-react in a BCV antigen-capture (AC) enzyme-linked immunosorbent assay (ELISA) system with monoclonal antibodies (MAbs) against N, spike glycoprotein, and hemagglutinin esterase glycoprotein proteins of BCV as coating antibodies. The same TOCVs could be detected with primers designed from the genome of infectious bronchitis virus (IBV) of chickens. These primers amplified a 1082-base pair region spanning portions of the membrane glycoprotein (M) and N protein genes of IBV and TCV. The TOCVs also cross-reacted in an AC-ELISA with MAbs against the M and subunit 2 of spike glycoprotein of IBV.

An analysis of the safety of the single dose, two drug regimens used in programmes to eliminate lymphatic filariasis

This review of the safety of the co-administration regimens to be used in programmes to eliminate lymphatic filariasis (albendazole + ivermectin or albendazole + diethylcarbamazine [DEC]) is based on 17 studies conducted in Sri Lanka, India, Haiti, Ghana, Tanzania, Kenya, Ecuador, the Philippines, Gabon, Papua New Guinea, and Bangladesh. The total data set comprises 90,635 subject exposures and includes individuals of all ages and both genders. Results are presented for hospital-based studies, laboratory studies, active surveillance of microfilaria-positive and microfilaria-negative individuals, and passive monitoring in both community-based studies and mass treatment programmes of individuals treated with albendazole (n = 1538), ivermectin (9822), DEC (576), albendazole + ivermectin (7470), albendazole + DEC (69,020), or placebo (1144). The most rigorous monitoring, which includes haematological and biochemical laboratory parameters pre- and post-treatment, provides no evidence that consistent changes are induced by any treatment; the majority of abnormalities appear to be sporadic, and the addition of albendazole to either ivermectin or DEC does not increase the frequency of abnormalities. Both DEC and ivermectin show, as expected, an adverse event profile compatible with the destruction of microfilariae. The addition of albendazole to either single-drug treatment regimen does not appear to increase the frequency or intensity of events seen with these microfilaricidal drugs when used alone. Direct observations indicated that the level of adverse events, both frequency and intensity, was correlated with the level of microfilaraemia. In non microfilaraemic individuals, who form 80-90% of the 'at risk' populations to be treated in most national public health programmes to eliminate lymphatic filariasis (LF), the event profile with the compounds alone or in combination does not differ significantly from that of placebo. Data on the use of ivermectin + albendazole in areas either of double infection (onchocerciasis and LF), or of loiais (with or without concurrent LF) are still inadequate and further studies are needed. Additional data are also recommended for populations infected with Brugia malayi, since most data thus far derive from populations infected with Wuchereria bancrofti.

Long-term efficacy of single-dose combinations of albendazole, ivermectin and diethylcarbamazine for the treatment of bancroftian filariasis

In a 'blinded' trial (in Sri Lanka, 1996-98) of 47 male asymptomatic microfilaraemic subjects with Wuchereria bancrofti infection, the safety, tolerability and filaricidal efficacy of 3 single-dose combination regimens were compared: albendazole 400 mg with ivermectin 200 micrograms/kg, albendazole 400 mg with diethylcarbamazine citrate (DEC) 6 mg/kg or albendazole 600 mg with ivermectin 400 micrograms/kg. Treated subjects were followed-up for 24 months. This represents the first long-term study using combinations of albendazole with DEC or ivermectin in the above doses against bancroftian filariasis. All subjects had pre-treatment microfilaria (mf) counts over 100/mL. All 3 treatments significantly reduced mf counts, with the albendazole-DEC-treated group showing the lowest mf levels at 18 and 24 months post-treatment. Filarial antigen tests suggested that all 3 treatments had significant activity against adult W. bancrofti; albendazole-DEC combination had the greatest activity according to this test, with antigen levels decreasing to 30.5% of pre-treatment antigen levels, 24 months after therapy. All 3 treatments were clinically safe and well tolerated. These results suggest that a single dose of albendazole 400 mg together with DEC 6 mg/kg is a safe and effective combination for suppression of microfilaraemia of bancroftian filariasis that could be considered for use in filariasis control programmes based on mass treatment of endemic populations.

Protective effect of folinic acid on low-dose methotrexate genotoxicity

INTRODUCTION

Methotrexate (MTX) is an antineoplastic agent widely used in low dose to treat patients with rheumatoid arthritis (RA). Its side effects can partly be explained by folate antagonism. Folinic acid (Leucovorin) is generally administered with MTX to decrease MTX-induced toxicity. However information regarding the inhibitory effect of folinic acid against cytogenetic damage caused by MTX is limited. The aim of this study was to assess the protective effect of folinic acid against MTX-genotoxicity.

METHODS

This study was done on Wistar albino rats and in patients with RA. Forty rats of both sexes were randomized into four equal groups and dosed in the following way: Group-I, distilled water vehicle; Group-II, 0.5 mg/kg folinic acid; Group-III, 0.5 mg/kg MTX; Group-IV, 0.5 mg/kg folinic acid plus 0.5 mg/kg MTX. Doses were given i.p., once daily for 8 consecutive days. A bone marrow chromosomal study and a micronucleus test were performed for each rat. Twenty patients with RA (5 males and 15 females) on a 10 mg weekly dose of MTX, i.m., for one month, were administered the same dose of MTX in addition to 10 mg of folinic acid as a single dose 4 hours after MTX administration, i.m., every week for another 4 weeks. Chromosomal studies as well as a micronucleus test were evaluated for each patient.

RESULTS

MTX produced a significant genetic injury as proved by the increased incidence of chromosomal aberration and micronuclei formation in Group-III animals. Inversely, folinic acid (group IV) produced a significant protection against genetic damages induced by MTX. In RA patients, folinic acid provides satisfactory improvement of MTX-induced genetic damage.

CONCLUSION

Folinic acid has a protective affect against MTX genotoxicity in human as well as in animal models.

Experimental bovine coronavirus in turkey poults and young chickens

The DB2 calf strain of bovine coronavirus (BCV) was used to inoculate 1-day-old specific-pathogen-free (SPF) turkey poults in three trials. In all trials, the birds developed clinical signs of enteritis at 48-72 hr postinoculation. Birds euthanatized at 3, 5, and 7 days postinoculation (DPI) had flaccid, pale intestines with watery contents, and the ceca were markedly enlarged with frothy contents. Coronavirus particles were detected by immune electron microscopy with BCV antibodies from the intestinal contents of birds killed at 3, 5, 7, and 12 DPI. Body weights of inoculated poults killed at 3, 5, and 7 DPI were significantly reduced as compared with controls. Hemagglutinating antibodies were detected in sera of convalescent birds at 12 DPI. However, experimental inoculation of 1-day-old SPF chicks in two trials with the same virus resulted in no clinical signs or macroscopic or microscopic lesions. No coronaviruses were detected from intestinal contents, and there were no significant differences in body weights of inoculated and noninoculated control chicks.

[Experimental corneal histological study after thermokeratoplasty with holmium laser]

PURPOSE

To analyze the histological results after application of LTK (Laser Thermal Keratoplasty). These changes explain the considerable regression of the refractive effect obtained.

METHODS

This is an experimental study in 25 eyes of albino rabbits after application of LTK, using the contralateral as a control. The histopathological evaluation was done at 12 hours, one week, one month, 3 months and 6 months of LTK spot application using various corneal stains.

RESULTS

At 12 hours there appears an intense intercellular edema and basophylia on the impact area, covering 100% of the stroma. After the first week a hyperplasia of the epithelium was found. At the first month there exists a gradual decrease of the basophylia, but the abnormal stromal structure remains. Over the third month, the collagen becomes acidophilous and with a laxer structure, thus showing the formation of new collagen. These changes remain constant at the 6th month.

CONCLUSION

The non-contact LTK induces an intense tissular damage associated to an inflammatory reaction, prior to the formation of new collagen tissue, changing the anatomic image of the cornea. These changes cause the regression of the effect produced by the holmium laser.

A preliminary analysis of Wuchereria bancrofti microfilarial antigens for potential use in diagnosis

Several antigens from the microfilarial stage of Wuchereria bancrofti have been identified using immunoblots of microfilarial antigens and screening with immune sera and tropical pulmonary eosinophilia (TPE) sera. This analysis revealed an array of antigens with apparent molecular weights of 14kDa, 35kDa, 42kDa, 63kDa, 88kDa, 97kDa and 200kDa. Among these only the 14kDa and 42kDa antigens were consistently recognized by most of the immune sera. A 132kDa antigen was recognized only by TPE sera. Analysis of rabbit immune sera revealed that the 42kDa antigen was shared by two developmental stages of W. bancrofti, namely L3 and mF. This antigen could become a potential vaccine candidate. The 14kDa antigen seems specific for the microfilarial stage and therefore could be a diagnostic marker for active infection. The 132kDa antigen could aid in the diagnosis of TPE.

Viral agents associated with poult enteritis and mortality syndrome: the role of a small round virus and a turkey coronavirus

Intestinal samples from turkey poults affected with poult enteritis and mortality syndrome (PEMS) were examined for viruses by immune electron microscopy and double-stranded RNA virus genome electropherotyping. Turkey coronavirus (TCV), avian rotaviruses, reovirus, and a yet undefined small round virus (SRV) were detected. The SRV and TCV were isolated and propagated in turkey embryos. Challenge of specific-pathogen-free turkey poults with SRV, TCV, or both resulted in mortality and clinical responses similar to those of natural PEMS. Our experiments indicate that SRV and TCV are possibly important agents in the etiology of PEMS and the combination of these infections might result in outbreaks with high mortality. The severity of clinical signs and mortality of PEMS are postulated to be partly related to the virus agents involved in individual outbreaks.

A novel synthesis of dibenzo[c,f]chromenes, dibenzo[c,h]chromenes and benzo[7,8]chromeno[3,4-f]isoindoles as antimicrobial agents

Naphtho[2,1-b]pyranone (3) was allowed to react with arylmethylenemalononitriles to yield 4-amino-5-oxo-2-aryl-5H-dibenzo[c,f]chromene-3-carbonitriles (4a,b); with ethyl 3,4-dichlorobenzylidene cyanoacetate to furnish dibenzo[c,f]chromene (5) and with elemental sulfur in dioxane containing piperidine to give thieno[3,4-d]naphtho[2,1-b]pyranone (6). Similarly, naphtho[1,2-b]pyranone (7) was reacted with arylmethylenemalononitriles and elemental sulfur to furnish dibenzo[c,h]chromenes (8) and thieno[3,4-d]naphtho[1,2-b]pyranone (10), respectively. Compound 10 underwent cycloaddition with N-arylmaleimides to yield benzo[7,8]chromeno[3,4-f]isoindoles (11a-c). Some of these compounds were screened in vitro for their antimicrobial activities.

Randomly amplified polymorphic DNA (RAPD) polymerase chain reaction assay for identification of Schistosoma mansoni strains sensitive or tolerant to anti-schistosomal drugs

The genetic differences between Schistosoma mansoni strains from different geographic areas that were reportedly resistant or sensitive to anti-schistosomal drugs were studied with randomly amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) polymerase chain reaction (PCR) assays. Of the 20 RAPD primers we chose, 19 showed the capacity to produce a medium to high level of amplification and 6 revealed difference PCR bands between drug-resistant and drug-sensitive strains. One particular primer, 5'-CAGCGACAAG-3', showed 2 major difference bands between praziquantel (PZQ)-resistant and PZQ-sensitive strains from the endemic area of Egypt. These results demonstrate that defined sequence primers could be applied as a useful tool for differentiating drug-resistant and -sensitive schistosome parasites in the field.

Re-examination of the diagnostic criteria of tropical pulmonary eosinophilia

There is no agreement on the minimum absolute eosinophil count essential for the diagnosis of tropical pulmonary eosinophilia (TPE) at present. The aim of this study was to determine this figure as well as to evaluate the other diagnostic criteria of TPE. The response to diethylcarbamazine (DEC) was tested in 98 patients [of whom 79 (80.6%) completed the study] be means of clinical scores, lung function tests and the absolute eosinophil counts. The minimum absolute eosinophil count necessary for the diagnosis of TPE was found to be 3300 for two reasons. Firstly there was a marked fluctuation in the mean percentage change of the absolute eosinophil count after treatment with DEC, when it was below 3225 cells mm-3, while the mean percentage reduction showed a remarkable stability when the eosinophil count exceeded 3600. Secondly there was a marked difference in the response to DEC in patients whose eosinophil counts were above and below these values. All patients who had eosinophil counts greater than 3600 responded to DEC and were diagnosed as cases of TPE. All of them were from filarial endemic areas. The total eosinophil count decreased by a mean of 92.5%, 3 months after administration of DEC. The sensitivities of the following tests in TPE were as follows: filarial antibody test (FAT) 30%, radiological changes 45.5%, erythrocyte sedimentation rate (ESR) 80%. The radiological changes and the ESR, but not the FAT, were helpful in differentiating TPE from those patients with TPE-like symptoms but with lower eosinophil counts, e.g. those with asthma. Patients with cough who had eosinophil counts of between 53 and 2000 cells mm-3, showed elevated filarial antibody levels in a significant number of cases when compared to asymptomatic subjects. (P < 0.001). Five of them responded to DEC. Three of these had filarial antibody in their serum and one had bilateral mottling on chest X-ray. These results suggest that atypical cases of TPE may exist. Our study has shown that the diagnosis of TPE rests on the following criteria: cough worse at night; residence in a filarial endemic area; the eosinophil count greater than 3300 cells mm-3, clinical and haematological response to DEC. The diagnosis is supported by radiological changes and elevated ESR. The FAT is of little value. The clinical benefit and the improvement in lung function which follows the administration of DEC was sustained up to a minimum period of 15 months.

The role of albendazole in programmes to eliminate lymphatic filariasis

Citing earlier advances in the treatment of lymphatic filariasis [particularly the effectiveness of single-dose diethylcarbamazine (DEC) in reducing microfilaraemia and its enhanced effectiveness when co-administered with single-dose ivermectin], Eric Ottesen, Mahroof Ismail and John Horton consider recent studies on the antifilarial activity of albendazole that have led to the current recommendations for its use in single-dose regimens in conjunction with either DEC or ivermectin for large-scale control/elimination programmes. Furthermore, the potential of albendazole as a macrofilaricide for treating individual patients with lymphatic filarial infections is emphasized as one of a number of important research questions that remain to be explored.

Efficacy of albendazole and its combinations with ivermectin or diethylcarbamazine (DEC) in the treatment of Trichuris trichiura infections in Sri Lanka

The efficacy of the drugs currently available for treatment of infection with Trichuris trichiura is low compared with that of the drugs used against roundworm and hookworm. Single-dose combinations of albendazole with ivermectin or of albendazole with diethylcarbamazine (DEC) have recently been seen to produce raid and sustained reductions in Wuchereria bancrofti microfilaraemia. This observation prompted the present study, on the efficacy of these combinations against trichuriasis. The drug regimens tested were albendazole (400 mg) alone, albendazole (400 mg) with ivermectin (200 micrograms/kg), and albendazole (400 mg) with DEC (6 mg/kg). Most (155) of the 176 children (4-14 years of age) who each provided a single, pre-treatment, stool sample were found positive for Trichuris ova. These 155 were each randomly allocated to one of the three treatment groups and checked for infection 3 weeks post-treatment, again by a single stool examination. Single-dose therapy with albendazole plus ivermectin produced a 'cure rate' (79.3%) and an egg-reduction rate (93.8%) which were significantly higher than the corresponding rates produced by albendazole alone or albendazole plus DEC (P < 0.01 for each). The efficacies of albendazole with DEC and of albendazole alone were statistically equivalent. Single-dose treatment with the albendazole-ivermectin combination appears to be highly effective against trichuriasis and could prove valuable for routine use.

Effect of mebendazole therapy during pregnancy on birth outcome

BACKGROUND

In areas endemic for hookworm, routine antenatal mebendazole therapy could greatly reduce the prevalence of anaemia in pregnancy. At present, however, this is not a widely accepted control strategy because of a lack of data on the safety of the drug. We assessed the effect of mebendazole therapy during pregnancy on birth outcome.

METHODS

A cross-sectional study was done in Sri Lanka, where prescription of mebendazole to women in the second trimester of pregnancy is recommended. Two hospitals were chosen for the study, and women who gave birth there between May, 1996, and March, 1997, were recruited. We compared the rates of major congenital defects, stillbirth, perinatal death, and low birthweight (< or = 1500 g) among babies of mothers who had taken mebendazole during pregnancy with those whose mothers had not taken an anthelmintic (controls).

FINDINGS

The rate of major congenital defects was not significantly higher in the mebendazole group than in the control group (97 [1.8%] of 5275 vs 26 [1.5%] of 1737; odds ratio 1.24 [95% CI 0.8-1.91], p=0.39). Among 407 women who had taken mebendazole in the first trimester (contrary to medical advice), 10 (2.5%) had major congenital defects (odds ratio vs controls 1.66 [0.81-3.56], p=0.23). The proportions of stillbirths and perinatal deaths were significantly lower in the mebendazole group (1.9 vs 3.3%, 0.55 [95% CI 0.4-0.77]), as was the proportion of low-birthweight babies (1.1 vs 2.3%, 0.47 [95% CI 0.32-0.71]).

INTERPRETATION

Mebendazole therapy during pregnancy is not associated with a significant increase in major congenital defects, but our results indicate that it should be avoided during the first trimester. This therapy could offer beneficial effects to pregnant women in developing countries, where intestinal helminthiases are endemic.

Laser thermokeratoplasty after lamellar corneal cutting

PURPOSE

To evaluate the effect of laser thermokeratoplasty (LTK) in eyes that previously had a lamellar corneal cut.

SETTING

University of Al-Azhar, Cairo, Egypt, and Instituto Oftalmológico de Alicante, Spain.

METHODS

In 15 eyes (10 patients), noncontact LTK was applied 6 to 8 weeks after a lamellar corneal cut had been made. Central pachymetry, keratometry, and videokeratography were performed and uncorrected visual acuity, best spectacle-corrected visual acuity (BSCVA), and manifest and cycloplegic refractions measured before and 1, 6, 12, and 18 months after LTK.

RESULTS

Mean follow-up was 19.13 months. Mean refraction was +5.93 diopters (D) +/- 1.9 (SD) before LTK and -0.43 +/- 1.5 D at 1 month, +1.63 +/- 1.6 D at 6 months, 1.91 +/- 1.41 at 12 months, and +2.01 +/- 1.5 D at the end of the study. Total regression did not occur in any case. Mean BSCVA before LTK was 0.66 +/- 0.2, and spontaneous visual acuity at the end of the study was 0.58 +/- 0.18. No patient lost any lines of preoperative BSCVA. There was no significant difference between the results at 12 months and at the end of the study.

CONCLUSION

Corneal lamellar cutting appeared to improve the magnitude of the refractive effect of noncontact LTK and to decrease the amount of regression.

A review of haematogenous osteomyelitis in children in Kuala Lumpur Hospital

We review 81 cases of acute haematogenous osteomyelitis from 1983 to 1990 to establish current pattern of clinical presentation, modes of treatment and success of therapy. Majority of the patient (70%) presented within a week of symptom and significant number of them came with fever and swelling of the affected limb. Sedimentation rate was found to be raised in all of them. Fifty-four (55%) of them were treated surgically. The average antibiotic time was one week by intravenous administration followed by additional oral therapy for period up to four weeks. Average follow-up was 9 months. Six of them (7.5%) end up with various complication which was believed to be due to delay in getting medical treatment.

Noncontact thermokeratoplasty to correct hyperopia induced by laser in situ keratomileusis

PURPOSE

To evaluate the efficacy and safety of noncontact holmium:YAG (Ho:YAG) laser thermokeratoplasty (LTK) for treating hyperopia induced by laser in situ keratomileusis (LASIK).

SETTING

Department of Ophthalmology, University of Alicante, Instituto Oftalmológico de Alicante, Alicante, Spain, and the University of Al-Azhar, Cairo, Egypt.

METHODS

Noncontact LTK was applied to 13 eyes (11 patients) with significant hyperopia after LASIK using a Ho:YAG laser (model gLase 210, Sunrise Technologies). Mean spherical equivalent before LTK was +4.60 diopters (D) +/- 1.40 (SD) (range +2.50 to +7.25 D). The results were evaluated 18 months after the LTK surgery.

RESULTS

A significant myopic shift developed in all eyes that gradually receded to emmetropia 6 to 8 weeks after LTK. After 12 months, refraction was relatively stable. At 18 months, there was a statistically significant difference between the mean uncorrected visual acuity (UCVA) before LTK (0.19 +/- 0.09) and mean postoperative UCVA (0.61 +/- 0.22) (P < .005). At the end of the study, there was a mean increase of 4.10 +/- 1.12 D in central keratometric power. Total regression did not occur in any eye.

CONCLUSION

Noncontact Ho:YAG LTK was safe and effective in correcting LASIK-induced hyperopia. The cutting of Bowman's layer and a thinner corneal center may contribute to the stability of LTK in such cases.

Efficacy of single dose combinations of albendazole, ivermectin and diethylcarbamazine for the treatment of bancroftian filariasis

In a 'blind' trial on 50 male asymptomatic microfilaraemic subjects with Wuchereria bancrofti infection, the safety, tolerability and filaricidal efficacy of a single dose of albendazole (alb) 600 mg alone or in combination with ivermectin (iver) 400 micrograms/kg or diethylcarbamazine citrate (DEC) 6 mg/kg was compared with a single dose of the combination DEC 6 mg/kg and iver 400 micrograms/kg over a period of 15 months after treatment. All but one subject, with 67 microfilariae (mf)/mL, had pre-treatment counts > 100 mf/mL. All 4 treatments significantly reduced mf counts, but alb/iver was the most effective regimen for clearing mf from night blood: 9 of 13 subjects (69%) were amicrofilaraemic by membrane filtration 15 months after treatment compared to one of 12 (8%), 3 of 11 (27%), and 3 of 10 (30%) in the groups treated with alb, alb/DEC, and DEC/iver, respectively. Filarial antigen tests suggested that all 4 treatments had significant activity against adult W. bancrofti; alb/DEC had the greatest activity according to this test, with antigen levels decreasing by 77% 15 months after therapy. All 4 regimens were well tolerated and clinically safe, although mild, self-limited systemic reactions were observed in all treatment groups. These results suggest that alb/iver is a safe and effective single dose regimen for suppression of microfilaraemia in bancroftian filariasis that could be considered for control programmes. Additional benefits of this combination are its potent, broad spectrum activity against intestinal helminths and potential relative safety in areas of Africa where DEC cannot be used for filariasis control because of co-endemicity with onchocerciasis or loiasis.

Human dirofilariasis caused by Dirofilaria (Nochtiella) repens in Sri Lanka

Human dirofilariasis due to Dirofilaria (Nochtiella) repens is a common zoonotic infection in Sri Lanka. Todate 70 cases are on record, and they include 3 expatriates from Russia, England and Korea, who were undoubtedly infected in Sri Lanka. Around 30-60% of dogs are infected with D. repens in various parts of the country and the mosquito vectors are Aedes aegypti, Armigeres subalbatus, Mansonia uniformis and M. annulifera. Unlike in other countries of the old world infection is most common in children under the age of 9 years, the youngest being 4 months old and the scrotum, penis and perianal regions of male children appear to be frequent sites for the worms. Dirofilaria (Dirofilaria) immitis is not present in Sri Lanka though it is present in neighbouring countries like India, and Malaysia.

Laser in situ keratomileusis to correct high myopia

PURPOSE

To evaluate the effectiveness, predictability, and safety of laser in situ keratomileusis (LASIK) in 143 eyes with myopia from 8.00 to 20.00 diopters (D).

SETTING

Alicante Institute of Ophthalmology, University of Alicante School of Medicine, Alicante, Spain.

METHODS

This prospective study comprised 143 eyes (94 patients) that had LASIK with the Chiron Automated Corneal Shaper and the VISX 20/20 excimer laser using a multizone profile and a sutureless hinged corneal flap technique.

RESULTS

Uncorrected visual acuity of 20/40 or better in 45.0% of eyes 3 months postoperatively and in 46.4% at 6 months. Best corrected visual acuity (BCVA) improved by 0.07 at 3 and 6 months and was stable after 3 months. Mean spherical equivalent was -13.19 diopters (D) +/- 2.89 (SD) preoperatively and +0.51 +/- 1.63 D at 3 months and +0.18 +/- 1.66 D at 6 months postoperatively. At 3 months, spherical equivalent was within 1.00 D of emmetropia in 57.5% of all eyes, 71.0% of eyes with a baseline refraction from -8.00 to -11.99 D (n = 59), 44.4% with a baseline refraction from -12.00 to -15.99 D (n = 54), and 53.0% of eyes with a baseline refraction from -16.00 to -20.00 D (n = 30). The respective 6 month percentages were 60.0, 72.4, 46.0, and 50.0%. The regression of effect was similar in all groups (approximately 0.50 D) between 1 and 3 months, although the high myopia group had further regression. Significant corneal steepening and an increase in corneal thickness occurred between 1 and 3 months. Flap thickness was always less than predicted with both the 130 microns plates, and achieved laser ablation was deeper than programmed. The relationships between postoperative refraction and preoperative keratometry and postoperative refraction and the difference in achieved versus programmed ablation were significant. Complications at 6 months included epithelial ingrowth, corneal flap melting, decentered ablation, and irregular astigmatism with loss of BCVA, although none was vision threatening.

CONCLUSION

In this study, LASIK was effective and predictable in the correction of high myopia but was more accurate for myopia up to 12.00 D. Current surgical algorithms must be modified to improve predictability in higher corrections. Longer follow-up is necessary to evaluate long-term incidence of vision-threatening complications.

Correction of Hyperopia with Non-contact Ho:YAG Laser Thermal Keratoplasty

PURPOSE

To assess the potential of non-contact holmium:YAG laser thermal keratoplasty to safely and effectively correct hyperopia up to +5.00 diopters (D).

METHODS

Non-contact laser thermal keratoplasty with a holmium:YAG laser using energies ranging from 215 to 255 mJ with 6, 7, and 8-min ablation zone diameters, was applied to 57 sighted eyes of 42 hyperopic patients in a controlled study. All patients were followed for 15 months after surgery.

RESULTS

Preoperative spectacle-corrected visual acuity returned to baseline levels from 2 to 6 weeks after treatment. Regression of effect was evident in all eyes, and after 15 months was total in 18 eyes (31.5%). The mean cycloplegic refraction before surgery was +3.80 +/- 0.22 D (range, +1.50 to +5.00 D); after surgery, it was +1.40 +/- 0.12 at 3 months, +1.69 +/- 0.19 D at 6 to 8 months, and +1.73 +/- 0.16 D at 15 months. At the end of the study, 41 eyes (71.9%) had an uncorrected visual acuity of 20/40 or better. Thirty-two eyes (58.8%) were within +/- 1.00 D of the intended refraction. Patient age and central pachymetric values were significantly correlated with regression (ANOVA, (p less than .005).

CONCLUSIONS

Regression of initial effect can be large with non-contact holmium:YAG laser thermal keratoplasty. We think the technique works best up to +3.00 D in older individuals with central corneal thickness less than 525 microns. Algorithms to improve the final results should include an initial calculated overcorrection adjusted on variables that influence regression such as patient age and corneal thickness.