The Helicobacter pylori single nucleotide polymorphisms SNPs associated with multiple therapy resistance in Colombia

The eradication of Helicobacter pylori (H. pylori) using multiple therapies is used as a prevention strategy. However, its efficacy has been compromised by the emergence of single nucleotide polymorphisms in genes associated with H. pylori's resistance to multiple antibiotics. To estimate antibiotic resistance rates associated with mutations in H. pylori genes in the high-cancer-risk population in Colombia, we included 166 H. pylori whole genome sequences from a cohort of individuals with a high risk of gastric cancer. By using the reference strain ATCC 26695, we identified mutations in specific genes to evaluate resistance rates for different antibiotics: 23S rRNA for clarithromycin, 16S rRNA for tetracycline, pbp1A for amoxicillin, gyrA for levofloxacin, and rdxA for metronidazole. The phylogenomic analysis was conducted using the core genome consisting of 1,594 genes of H. pylori-ATCC 26695. Our findings revealed that the resistance rate of H. pylori to clarithromycin was 3.62%, primarily associated with mutations A2143G and A2142G in the 23S rRNA gene. For tetracycline, the resistance rate was 7.23%, with mutations A926G, A926T, and A928C observed in the 16S rRNA gene. Amoxicillin resistance was found in 25.9% of cases, with observed mutations in the pbp1A gene, including T556S, T593, R649K, R656P, and R656H. In the gyrA gene, mutations N87K, N87I, D91G, D91N, and D91Y were identified, resulting in a resistance rate of 12.04% to levofloxacin. The most common mutations in the rdxA gene associated with metronidazole resistance were a stop codon, and mutations at D59N and D59S, resulting in a resistance rate of 99.3%. The high resistance rate of H. pylori to metronidazole indicated that this drug should be excluded from the eradication therapy. However, the resistance rates for tetracycline and clarithromycin did not exceed the established resistance threshold in Colombia. The increased resistance rate of H. pylori to levofloxacin and amoxicillin may partially explain the observed therapeutic failures in Colombia. The phylogenomic tree showed that the H. pylori isolate belongs to its own lineage (hspColombia). These findings offer valuable insights to enhance the characterization of treatment protocols for the specific H. pylori lineage (hspColombia) at the local level.

Spinal subarachnoid haematoma after neuraxial anaesthesia in a patient with polycythaemia vera

Polycythaemia vera is a common haematological proliferative disorder. It is characterised by uncontrolled red cell production with ensuing peri-operative vaso-occlusive and haemorrhagic complications. Spinal haematoma after neuraxial anaesthesia is rare; most cases are associated with technical difficulties or bleeding disorders. Current consensus opinion suggests that neuraxial anaesthesia in patients with polycythaemia vera is safe due to a lower risk of thrombotic events and hypoxaemia compared with general anaesthesia. We report a case of a spinal subarachnoid haematoma after uneventful neuraxial anaesthesia in a patient with optimised polycythaemia vera. Despite an emergent laminectomy, the patient developed permanent motor deficits. This report highlights that although neuraxial anaesthesia is recommended by many authors, patients with polycythaemia vera can paradoxically have an increased haemorrhagic risk from platelet dysfunction and acquired von Willebrand disease. Clinicians proceeding with surgery under neuraxial anaesthesia should appreciate these risks even in patients with normal or apparently elevated thrombotic states. This case also demonstrates that traditional coagulation tests may need to be complemented by pre-operative platelet function tests and screening for von Willebrand disease. Finally, the importance of the patient participation in the choice of the anaesthesia technique cannot be understated, with specific attention paid to this frequently unrecognised risk.

Cinética de degradación ruminal in situ de ensilado de rastrojo de maíz (Zea mays) con niveles crecientes de urea

Se estudió el efecto de la inclusión de urea sobre la composición y cinética de degradación ruminal in situ en el ensilado de rastrojo de maíz. Se partió de cuatro de tratamientos al adicionar el 0, 1, 2 y 3% de urea a una mezcla de rastrojo de maíz con el 10% de melaza. Se elaboraron 128 microsilos (3 kg/unidad y 4 repeticiones por tratamiento). La apertura de los silos se realizó a los 7, 14, 21, 28, 35, 42, 49 y 56 días. Se determinó el contenido de la materia seca (MS), materia orgánica (MO), proteína bruta (PB), FND y FAD. La degradabilidad in situ se obtuvo mediante el método de Mehrez y Orskov y la degradabilidad de MS y PB mediante el análisis de los residuos con el método Kjeldhal. Los datos se analizaron con el procedimiento GLM y el test de Tukey (P±

Telmisartan-induced sprue-like enteropathy: a case report

A possible case of sprue-like enteropathy (SLE) induced by the use of telmisartan is reported. Telmisartan is an angiotensin-receptor II blocker (type 1) used for the treatment of hypertension. Several cases of SLE associated with olmesartan and other drugs of the same group have been reported. In all cases, SLE resolved following therapy withdrawal. We describe the case of an 80-year-old woman who presented with diarrhoea and abdominal pain. In the past 5 years she had been treated with telmisartan 40 mg once a day for hypertension, so we hypothesised that symptoms might be caused by telmisartan. After treatment discontinuation, diarrhoea disappeared. Three causality algorithms were applied and revealed a possible or likely causal relationship. At present, the patient remains asymptomatic. There is a causal relationship between the use of telmisartan and SLE. This association should be taken into account by physicians when prescribing and reviewing drug therapies.

Knowledge, attitudes, practices about HIV and implications in risk and stigma prevention among French Guianese and Brazilian border inhabitants : Beliefs about HIV among border inhabitants

BACKGROUND

The border area between French Guiana and Brazil is an active HIV-transmission zone. The aim of the present study was to describe HIV knowledge, risk and the level of stigma among inhabitants of this border area.

METHODS

A cross-sectional study was conducted among 621 inhabitants over 18 years of age in the border cities of Saint-Georges-de-l'Oyapock in French Guiana and Oiapoque in Brazil. It was conducted between October 2017 and February 2018. An anonymous standardized questionnaire was filled out by culturally-trained mediators, then analyzed using STATA 12.

RESULTS

Almost half (45.9%) of the individuals had a low education level. Participants whose native language was Portuguese or French demonstrated better HIV knowledge than other populations, notably native Amerindian and creole-speaking people. HIV risk behavior was more frequent in men and in younger age groups. People with good HIV knowledge reported having performed more HIV tests in the last year than participants with poor knowledge. The stigma level was high and reported in 74.8% of respondents.

CONCLUSIONS

These results illustrate the need for initiatives to improve HIV prevention among autochthonous populations on both sides of this border area. Cross-border collaboration on health policies could produce common key messages adapted to the education level and multi-linguistic populations who live in this area.

The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

BACKGROUND

The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications.

METHODS

ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery.

RESULTS

The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784.

CONCLUSIONS

This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance.

CLINICAL TRIAL REGISTRATION

NCT03044899.

Baropodometry on patients after total knee arthroplasty

PURPOSE

It is well known that total knee replacement surgery decreases pain and improves function, but the effect on postural assessment needs to be studied better with the use of new technological devices. Total knee arthroplasty (TKA) improves motor coordination and stability of the knee. On the other hand, changing joint functionality can modify the balance. The aim of this trial is to record and analyze the static and dynamic baropodometric data of patients in the first few months following joint replacement. For the physiatrist, this tool can be useful to check if the rehabilitation treatment protocols and times are correct.

METHODS

We designed a prospective observation longitudinal study to assess postural stability following TKA. Between December 2014 and May 2015, sixty consecutive patients were recruited through local orthopedic physician offices and hospitals. The patients scheduled to undergo TKA were recruited and were monitored before surgery (T0) and at 1 (T1), 3 (T2) and 6 months (T3) after knee surgery. The correction of varus/valgus deviation at X-ray and the Knee Society Score were performed to verify the functional recovery. We used static and dynamic baropodometric analysis to evaluate postural assessment.

RESULTS

After surgery, there was a significant improvement in physiological alignment of knee axes (p < 0.0001) and of Knee and Function Scores (excellent, mean values 80.5 and 80.7, respectively, p < 0.0001). The static analysis showed that the center of gravity and the pressure on the foot of the operated limb were corrected toward the physiological center (p < 0.0001) and the body weight displaced to the forefeet and to the hindfeet reduced bilaterally (p < 0.0001). The type of footprint did not change. The dynamic analysis confirmed the significant normalization of the pressure on the foot of the operated limb at all follow-ups (p < 0.0001). The percentage of load was reduced on the operated limb (p = 0.0096) and speed of step, cadence and semi-step length increased (p < 0.0001).

CONCLUSION

These data show the progressive recovery of stability after TKA from the immediate postoperative to the subsequent months. The clinical and functional improvement correlated with a load redistribution between the two limbs. The baropodometry could be an excellent noninvasive method for monitoring effects of rehabilitation treatment.

Sequential vs. prolonged 14-day triple therapy for Helicobacter pylori eradication: the meta-analysis may be influenced by 'geographical weighting'

BACKGROUND

Sequential therapy is a first-line regimen obtaining satisfactory Helicobacter pylori eradication. Triple therapy prolongation improves the success rate even if a recent meta-analysis showed satisfying results only for the 14-day regimen. Studies from Africa and North America were unavailable in previous meta-analyses.

AIM

To perform a meta-analysis comparing sequential vs. prolonged 14-day triple therapy with regard to 'geographic weighting' by considering subgroups analysis according to metronidazole/clarithromycin low and high resistance areas.

METHODS

Based on PRISMA recommendations, we considered all first-line clinical studies from 2003 to November 2014. Randomised clinical trials (RCTs) were included by a search on PubMed, MEDLINE, Science Direct, EMBASE. Data on eradication rates were expressed as ITT. Risk ratio (RR), pooled RR and 95% confidence intervals were calculated by the Mantel-Haenszel method. Data were entered into RevMan 5.2 software (Nordic Cochrane Centre) using a random-effects model.

RESULTS

Databases identified 194 studies; seven met the inclusion criteria. Overall results showed a similar effectiveness of the two regimens considered (RR = 0.99; 95% CI = 0.94-1.05; p = 0.75). In areas with high resistance to clarithromycin, sequential was superior to 14-day triple therapy (RR = 0.95; 95% CI = 0.90-1.00; p = 0.03). In areas with high metronidazole resistance, sequential and 14-day triple therapy were equivalent (RR = 0.99; 95% CI = 0.91-1.08; p = 0.82).

CONCLUSIONS

'Geographic weighting' could be the main factor affecting the lack of differences between sequential and 14-day triple therapy outcomes.

Evaluation of sunscreen safety by in vitro skin permeation studies: effects of vehicle composition

For sunscreens to be safe and effective, the lowest possible UV-filter percutaneous absorption should be achieved. In this paper, we evaluated in vitro release and permeation through human skin of two UV-filters, octyl methoxycinnammate (OMC) and butyl methoxydibenzoyl methane (BMBM) from six commercial O/W emulsions and we estimated their margin of safety (MoS). OMC and BMBM in vitro release and skin permeation were investigated in Franz-type diffusion cells and permeation data were used to calculate MoS. OMC in vitro skin permeation depended on both its concentration and vehicle composition while BMBM skin permeation depended on its release from the vehicle. MoS values were well beyond the lowest limit accepted for safe products. Although sunscreen skin permeation may depend on many factors, the commercial products investigated are safe under normal "in use" conditions.

In vitro evaluation on a model of blood brain barrier of idebenone-loaded solid lipid nanoparticles

The aim of this study was to evaluate in vitro the permeation of the antioxidant agent Idebenone (IDE) loaded into solid lipid nanoparticles (SLN) across MDCKII-MDR1 cell monolayer, selected as an in vitro model of the Blood Brain Barrier (BBB). SLN were prepared using cetyl palmitate as solid lipid and different non-ionic surfactants, oleth-20, ceteth-20 and isoceth-20, by the phase inversion temperature (PIT) technique. The resulting SLN showed physiological pH and osmolarity values, a mean particle diameter in the range of 33-63 nm, a single peak in size distribution, and a zeta potential ranging from +3.14 to -2.89 mV. When incubating these SLN in Simulated Body Fluid (SBF), the particle size was maintained for all samples throughout the study. IDE permeability across MDCKII-MDR1 cell monolayers from the SLN under investigation was 0.40-0.53 fold lower than free IDE and no significant difference was observed comparing IDE permeation from all the SLN tested. It is noteworthy that IDE loading into SLN avoided the use of an organic solvent to solubilize IDE, a poor water soluble compound, allowing the parenteral administration of this drug in aqueous vehicles. Furthermore, the results of in vitro transport studies, performed using fluorescein-dextran 4000 (FD4) and diazepam (DZ) as markers of the paracellular pathway and the transcellular pathway, respectively, pointed out that IDE could permeate via a transcellular pathway. Therefore, these novel nanocarriers could be regarded as a promising strategy to design delivery systems for IDE administration to the brain, deserving further investigations under in vivo conditions.

Air sampling methods to evaluate microbial contamination in operating theatres: results of a comparative study in an orthopaedics department

AIM

To evaluate the level of microbial contamination of air in operating theatres using active [i.e. surface air system (SAS)] and passive [i.e. index of microbial air contamination (IMA) and nitrocellulose membranes positioned near the wound] sampling systems.

METHODS

Sampling was performed between January 2010 and January 2011 in the operating theatre of the orthopaedics department in a university hospital in Southern Italy.

FINDINGS

During surgery, the mean bacterial loads recorded were 2232.9 colony-forming units (cfu)/m(2)/h with the IMA method, 123.2 cfu/m(3) with the SAS method and 2768.2 cfu/m(2)/h with the nitrocellulose membranes. Correlation was found between the results of the three methods. Staphylococcus aureus was detected in 12 of 60 operations (20%) with the membranes, five (8.3%) operations with the SAS method, and three operations (5%) with the IMA method.

CONCLUSION

Use of nitrocellulose membranes placed near a wound is a valid method for measuring the microbial contamination of air. This method was more sensitive than the IMA method and was not subject to any calibration bias, unlike active air monitoring systems.

Use of solid phase extraction (SPE) to evaluate in vitro skin permeation of aescin

The aim of this work was to evaluate the feasibility of assessing aescin in vitro permeation through human skin by determining the amount of aescin permeated using conventional HPLC procedures after extraction of skin permeation samples by means of solid phase extraction (SPE). Aescin in vitro skin permeation was assessed from aqueous solutions and gels using both Franz-type diffusion cells and flow-through diffusion cells. The SPE method used was highly accurate (mean accuracy 99.66%), highly reproducible (intra-day and inter-day variations lower than 2.3% and 2.2%, respectively) and aescin recovery from normal saline was greater than 99%. The use of Franz-type diffusion cells did not allow us to determine aescin flux values through excised human skin, therefore aescin skin permeation parameters could be calculated only using flow-through diffusion cells. Plotting the cumulative amount of aescin permeated as a function of time, linear relationships were obtained from both aqueous solution and gel using flow-through diffusion cells. Aescin flux values through excised human skin from aqueous gel were significantly lower than those observed from aqueous solution (p < 0.05). Calculating aescin percutaneous absorption parameters we evidenced that aescin partition coefficient was lower from the aqueous gel with respect to the aqueous solution. Therefore, the SPE method used in this study was suitable to determine aescin in vitro skin permeation parameters from aqueous solutions and gels using a conventional HPLC method for the analysis of the skin permeation samples.

PLA/PLGA nanoparticles for sustained release of docetaxel

This study investigates the potentiality of nanosphere colloidal suspensions as sustained release systems for intravenous administration of docetaxel (DTX). Nanospheres were prepared by solvent displacement method using polylactic acids (PLA) at different molecular weight and polylactic-co-glycolic (PLGA) as biodegradable matrices. The systems were characterized by light scattering analysis for their mean size, size distribution and zeta potential and by scanning electron microscopy (SEM) for surface morphology. The average diameters of the nanoparticles ranged from 100 to 200 nm. Negative zeta potential values were observed for all systems, particularly the nanospheres produced with the lowest molecular weight PLA showed a zeta potential value of -28mV. Differential scanning calorimetry analysis (DSC) suggested that DTX was molecularly dispersed in the polymeric matrices. A biphasic release of DTX was observed for all colloidal suspensions, after a burst effect in which about 50% (w/w) of the loaded drug was released a sustained release profile for about 10 days was observed. To evaluate the influence of the polymeric carrier on the interaction of DTX with biological membranes, we performed an in vitro study using lipid vesicles made of dipalmitoylphosphatidylcholine (DPPC) as a biomembrane model. DSC was used as a simple and not invasive technique of analysis. DTX produced a depression of DPPC pretransition peak, no variation of the main phase transition temperature and a significative increase of DeltaH value, showing a superficial penetration of the drug into DPPC bilayer. Kinetic experiments demonstrated that the release process of DTX form nanospheres is affected by the molecular weight of the employed polymers.

A femorotibial joint swelling with popliteal lymph node enlargement in a Rottweiler

A 9-year-old male Rottweiler was presented to the Veterinary Medical Hospital Montenegro, Porto, Portugal with a large mass medial to the left stifle and radiographic signs of bone lysis involving the proximal tibia, fibula, and distal femur. A fine-needle aspiration was obtained from left popliteal lymph node, which was markedly enlarged. Cytologic examination revealed a highly cellular sample consisting of pleomorphic cells with marked anisocytosis and anisokaryosis and other criteria of malignancy. Some cells contained intracytoplasmic, granular, dark brown material, consistent with hemosiderin. Histologic evaluation of the surgically-excised lymph node revealed a neoplastic proliferation of histiocytic cells, with marked pleomorphism; occasional cells were erythrophagocytic. Mitotic figures were frequently observed, and many were atypical. Histologic findings were consistent with malignant histiocytosis. Necropsy examination confirmed the diagnosis of malignant histiocytosis with systemic involvement affecting most organs examined. This case of malignant histiocytosis case had an atypical clinical presentation, mimicking a musculoskeletal disorder. It underlines the importance of cytology as a simple, inexpensive, rapid and noninvasive complementary exam in routine clinical practice that can permit early diagnosis of the disease and timely selection of the most adequate therapy.

¿Cuándo sería más rentable realizar una endoscopia digestiva alta para establecer la presencia de varices esofágicas en pacientes con cirrosis?

INTRODUCTION

Variceal hemorrhage occurs in 25 to 35% of cirrhotic patients and is associated with significant morbidity and mortality and elevated hospital costs. Endoscopic exploration of gastroesophageal varices (GEV) in cirrhotic patients increases costs and involves a certain degree of invasiveness and discomfort for patients. The association between the presence of GEV and spleen size, liver function and platelet count is controversial. The aim of this study was to determine the correlation between liver function, evaluated by Child-Pugh (Ch-P) classification, platelet count (PC) and spleen volume index (SVI) with the presence of GEV in patients with cirrhosis managed in the outpatient setting.

PATIENTS AND METHOD

Sixty-eight patients were included. In all patients, a medical history was taken and biochemical tests, mode B and Doppler abdominal ultrasonography, and upper digestive video-endoscopy were performed.

RESULTS

A total of 76.47% of the patients were men and 23.53% were women. The median age was 52.8 12.4 years. More than half (54.41%) of the patients were Ch-P grade A, 41.18% were grade B and 4.41% were grade C. The most frequent causes of cirrhosis were alcohol in 52.95% and hepatitis C virus in 17.65%. Esophageal varices (EV) were found in 85.29% of the patients. The median SVI was 50.5 9.2 and the median PC was 150 26 x 109/L. A correlation was found between the presence of EV, SVI >or= 45 and PC < or= 100 x 109/L (r = 0.327; p = 0.006). No correlation was found between the presence of EV and Ch-P grade A. In the multivariate analysis, only the presence of EV was associated with SVI >or= 45 (OR 7.4; 95% CI, 1.30-77.7; p = 0.02).

CONCLUSION

The presence of EV in cirrhotic patients managed in the outpatient setting was correlated with SVI >or= 45 and PC <or= 100 x 109/L.

Enhancer effects on in vitro corneal permeation of timolol and acyclovir

The aim of this study was to evaluate the ability of two non-toxic skin penetration enhancers, N-methylpyrrolidone (NMP) and a positively charged phospholipid mixture (PS), to increase in vitro corneal permeation of timolol maleate (TM) and acyclovir (AC) in comparison with two corneal absorption promoters, polyethylene glycol octadecyl ether (Brij 78) and sodium taurocholate (TA). In vitro experiments were performed on corneas from albino rabbits which were mounted in a perfusion apparatus. The concentrations of the enhancers being tested were: Brij 78 1%, PS 1%, TA 1%, NMP 5%, NMP 10%. The safety of the enhancers being tested was assessed in vitro by determining their effects on corneal hydration and in vivo by means of a modified Draize test. Calculating the amount of drug permeated at different time points (90 and 180 min) we observed that TA, PS and NMP 5% significantly increased the cumulative amount of AC permeated after 90 min but only PS was effective after 180 min. TA, Brij 78 and PS were able to increase significantly the amount of TM permeated after 90 min but after 180 min only Brij 78 retained its effect. TA, Brij 78 and NMP 10% significantly increased the percent hydration levels (% HL) compared to the control while PS and NMP 5% did not affect % HL. The results of in vivo ocular tolerability studies showed that the enhancers which caused an in vitro increase of % HL produced in vivo conjunctival and/or corneal damages. The results of this study suggest that PS could be regarded as a potential corneal enhancer to increase the intraocular bioavailability of AC and TM.

Development and optimization of polymerase chain reaction-based malaria diagnostic methods and their comparison with quantitative buffy coat assay

Polymerase chain reaction (PCR)-based assays targeting the small-subunit rRNA were developed and evaluated, allowing for the simultaneous diagnosis of Plasmodium falciparum and Plasmodium vivax DNA in human blood samples. The PCR methods and quantitative buffy coat (QBC) were compared in 402 patients. The heminested PCR method showed a sensitivity of 97.4%, which was superior to the sensitivity of the QBC method (91.7%, P < 0.05), to simple PCR (84.6%, P < 0.001), and to PCR with digoxigenin labeling (PCR-DIG) (88.5%, P < 0.001). The PCR-DIG and QBC analyses were more sensitive than simple PCR (P < 0.003 and P < 0.05, respectively). There was no significant difference between the sensitivities of the QBC assay and the PCR-DIG assay. The specificity for the 3 PCR-based methods was 100%, superior to the specificity calculated for the QBC assay (88.95%, P < 0.009). The frequency of a positive result in groups from endemic areas but without detectable parasitemia increased, in order, from simple PCR, QBC test, PCR-DIG, to heminested PCR. An association between a positive PCR result and a history of malaria was also found. Taken together, these data suggest that this technology could be further developed to screen people with oligoparasitemia and to monitor malaria treatment.

Classic Pick's disease type with ubiquitin-positive and tau-negative inclusions: case report

We report on a patient presenting Pick's disease similar to the one reported by Pick in 1892, with ubiquitin-positive and tau-negative inclusions. His diagnosis was made on the basis of clinical (language disturbance and behavioural disorders), neuropsychological (progressive aphasia of the expression type and late mutism), neuroimaging with magnetic resonance (bilateral frontal and temporal lobes atrophy) and brain single photon emission computed tomography (frontal and temporal lobes hypoperfusion) studies. Macroscopic examination showed atrophy on the frontal and temporal lobes. The left hippocampus displayed a major circumscribed atrophy. The diagnostic confirmation was made by the neuropathological findings of the autopsy that showed neuronal loss with gliosis of the adjacent white matter and apearance of status spongiosus in the middle frontal and especially in the upper temporal lobes. There were also neuronal swelling (ballooned cell) and argyrophilic inclusions (Pick's bodies) in the left and right hippocampi. Anti-ubiquitin reaction tested positive and anti-tau tested negative.

Synthesis, stability and anticonvulsant activity of two new GABA prodrugs

4-(3,4-Dihydro-2,4-dioxo-2H-1,3-benzoxazin-3-yl)-butyric acid (7) and its ester 6, two potential gamma-aminobutyric acid (GABA) prodrugs, were synthesized and studied to determine their stability in aqueous buffer and their susceptibility to undergo enzymatic hydrolysis in vitro (mouse plasma). Both compounds were fairly stable in aqueous media, (t1/2 = 68.2 h and 25.7 h, respectively). The 3,4-dihydro-2,4-dioxo-2H-1,3-benzoxazine ring underwent enzymatic hydrolysis (t1/2 = 5.8 h) in compound 7, whereas in compound 6 it seemed not to be opened by mouse plasma esterases within the observation time (3h). Both compounds were tested for their anticonvulsant activity in pentetrazole (PTZ) treated mice, and showed significant activity. Compound 7, administered as sodium salt 8, was active at relatively low doses and can be considered a very interesting GABA prodrug.

Anticonvulsive activity of a new GABA mimetic drug

This study examines the pharmacological profile of a new GABA mimetic drug, 4-[(2H)-1,3-benzoxazine-2,4(3H)-dione]-butyric acid (BXDBA), using both a behavioral and an anticonvulsive study. The behavior elements considered were locomotor activity, motor coordination, catalepsy, behavior and antinociception. The anticonvulsive study was performed using the convulsive agent bicuculline. BXDBA [10, 20 and 40 mg/kg, intraperitoneally (i.p.)] did not significantly modify animal behavior or the nociceptive threshold of the animals. The anticonvulsive study indicated that BXDBA (10, 20 and 40 mg/kg, i.p.), injected 60 min before bicuculline (10 micrograms/intracerebroventricular (i.c.v.)/mouse) induced a dose-dependent and significant reduction of the convulsive activity of bicuculline whereas it was ineffective if injected immediately before the convulsive agent. Our data indicate that this new GABA mimetic drug possesses good anticonvulsive activity and its ability to block bicuculline-induced convulsions suggests that it could be a GABAA mimetic drug. Furthermore, since BXDBA is able to act after systemic administration, our data suggest that this new GABA mimetic drug crosses the blood-brain barrier.

Transport of alpha-tocopherol and its derivatives through erythrocyte membranes

PURPOSE

To investigate the transport of alpha-tocopherol (T), tocopherol succinate (TS) and tocopherol succinate-3-glucose (a newly synthetized, less hydrophobic T ester; TSG) through bovine erythrocyte membranes.

METHODS

Our experiments were carried out on erythrocytes (obtained from heparinized fresh bovine blood), because they represent a suitable model for investigations of membrane transport.

RESULTS

T was shown to reside almost completely in the suspension medium, while the greater part of TS disappeared from the suspension medium and was mainly incorporated into erythrocyte membranes. In comparison with T, a larger amount of TSG was incorporated into erythrocyte membranes and taken up by cells; however the TSG intracellular accumulation was significantly lower than that observed with TS. Furthermore, the transport of TS and TSG was partially inhibited by p-chloromercuribenzenesulfonate (which inhibits monocarboxylate uptake; PCMBS) and by maltose (a competitive inhibitor of glucose transport) respectively, with a concomitant increase in drug membrane incorporation. No significant change in drug transport was observed in the presence of 4,4'-diisothiocyanostilbene-2,2'-disulfonate, a selective and irreversible blocker of band 3 protein (DIDS).

CONCLUSIONS

Our results show 1) the existence of large differences in membrane incorporation of T, TS and TSG (very likely caused by differing abilities to fill spaces in the lipid bilayer) and 2) a specific contribution of the monocarboxylate transport protein and of the glucose transport protein in the cellular uptake of TS and TSG, respectively. A tempting suggestion is that the unique cytoprotective properties of TS may be related to the differences in the transmembrane mobility observed between T and its succinate ester. Furthermore, T conjugation to a monocarboxylate or glycoside moiety could provide suitable substrates for active membrane transport, thus appearing as a promising pharmaceutical strategy for the improved delivery of tocopherol derivatives.

Synthesis and pharmacological evaluation of oligoethylene ester derivatives as indomethacin oral prodrugs

Five indomethacin oligoethylene ester derivatives (3-7) were synthesized and evaluated for their anti-inflammatory, analgesic, and ulcerogenic activity after oral administration. The molecular weight of the oligoethylene glycols used for synthesizing esters 3-7 ranged from 106 to 282. The chemical and enzymatic stabilities of esters 3-7 were evaluated in pH 7.4 and 2.0 buffers and in human plasma, respectively. All the prodrugs showed a good stability both in pH 7.4 phosphate buffer and in pH 2.0 buffer, and they were readily hydrolyzed by human plasma. Esters 3-7 showed an anti-inflammatory activity, determined as the percent inhibition of carrageenan-induced edema, similar to that of indomethacin, although at higher doses. From writhing test results, we observed that all the prodrugs exhibited better or similar analgesic activity compared to indomethacin. Esters 3-7 were significantly less irritating to the gastric mucosa than indomethacin, after oral administration, and esters 3-5 did not show any ulcerogenic activity, although they were administered at higher doses than indomethacin.

Bioavailability of two formulations of acetylsalicylic acid gums

Bioavailability studies have been performed with ten healthy volunteers on different dosage forms of acetylsalicylic acid (ASA) in order to assess the bioavailability of two different ASA gums compared with commercial ASA tablets. The results of this study show that ASA is more readily absorbed and eliminated after administration of gum formulations than after administration of tablets, but the bioavailability obtained from the gums was lower than that observed from the tablets.

Child pedestrian injury: a population-based collision and injury severity profile

Linked multiple data sources were analyzed to provide a population-based collision and injury severity profile among pedestrians under 20 years of age struck by a motor vehicle during 1986-1987 in Hartford, Connecticut. Data sources included police accident reports, medical examiner records, and hospital charts. There were 234 motor vehicle-pedestrian collisions reported to the police in the study period. Of these, 213 were Hartford residents resulting in an annual age-specific pedestrian collision rate of 22.8 per 10,000 persons. A spot map of collision location reveals several well-defined geographic areas, which includes nearly half (45%) of the motor vehicle-pedestrian collisions. We reviewed 143 of 192 medical charts (75%) and 6 medical examiner records. The case fatality rate was 4.2% and the mean Injury Severity Score was 4.4. These findings will be useful for designing, implementing, and evaluating a targeted child pedestrian safety program.