Azithromycin and moxifloxacin resistance determinants in Mycoplasma genitalium in Lleida, Spain

OBJECTIVE

Mycoplasma genitalium (MG) is a microorganism related to sexually transmitted infections. Antibiotic resistance of MG leads to an increase in treatment failure rates and the persistence of the infection. The aim of this study was to describe the most frequent mutations associated with azithromycin and moxifloxacin resistance in our geographical area.

METHODS

A prospective study from May 2019 to May 2023 was performed. MG-positive samples were collected. Real-time PCRs (AllplexTM MG-AziR Assay and AllplexTM MG-MoxiR Assay, Seegene) were performed in MG positive samples to detect mutations in 23S rRNA V domain and parC gene.

RESULTS

A 37.1% of samples presented resistance determinants to azithromycin and the most common mutation detected was A2059G (57.9%). Resistance to moxifloxacin was studied in 72 azithromycin-resistant samples and 36.1% showed mutations, being G248T the most prevalent (73.1%).

CONCLUSIONS

The resistance to different lines of treat ment suggests the need for a targeted therapy and the performing of a test of cure afterwards.

Efficacy of sacral transcutaneous electrical nerve stimulation in patients with overactive bladder refractory to anticholinergic treatment: a prospective multi-center study

OBJECTIVE

To determine whether sacral transcutaneous electrical nerve stimulation (S-TENS) is an effective treatment in patients refractory to anticholinergic drugs (Achs).

MATERIALS AND METHODS

A prospective multi-center study of patients with overactive bladder (OB) refractory to Achs treated with S-TENS from 2018 to 2021 was carried out. S-TENS was applied over 3 months. Symptom progression was assessed using the voiding calendar and the Pediatric Lower Urinary Tract Symptoms Score (PLUTSS), excluding questions 3 and 4 -referring to enuresis- so that progression of daytime symptoms only (LUTS variable) was analyzed.

RESULTS

66 patients -50% of whom were female- were included, with a mean age of 9.5 years (range: 5-15). S-TENS significantly lowered PLUTSS (19.1 baseline vs. 9.5 final, p< 0.001) and LUTS (13.1 baseline vs. 4.8 final, p< 0.001). It also reduced the number of mictions (8.5 baseline vs. 6.4 final, p< 0.001), while increasing urine volume in the voiding records (214 ml baseline vs. 258 ml final, p< 0.001). Enuresis was the only variable refractory to S-TENS. Complication rate was 3% (2 patients with dermatitis in the S-TENS application area).

CONCLUSIONS

S-TENS is effective and safe in the short-term in patients with OB refractory to Achs. Further studies assessing long-term efficacy and potential relapses are required.

Emerging Hyalomma lusitanicum: From identification to vectorial role and integrated control

In the Mediterranean basin, the tick species Hyalomma lusitanicum Koch stands out among other species of the Hyalomma genus due to its wide distribution, and there is great concern about its potential role as a vector and/or reservoir and its continuous expansion to new areas because of climate warming and human and other animal movements. This review aims to consolidate all the information on H. lusitanicum, including taxonomy and evolution, morphological and molecular identification, life cycle, sampling methods, rearing under laboratory conditions, ecology, hosts, geographical distribution, seasonality, vector role and control methods. The availability of adequate data is extremely relevant to the development of appropriate control strategies in areas where this tick is currently distributed as well as in new areas where it could become established in the near future.

Invariant representations in deep learning for optoacoustic imaging

Image reconstruction in optoacoustic tomography (OAT) is a trending learning task highly dependent on measured physical magnitudes present at sensing time. A large number of different settings and also the presence of uncertainties or partial knowledge of parameters can lead to reconstruction algorithms that are specifically tailored and designed to a particular configuration, which could not be the one that will ultimately be faced in a final practical situation. Being able to learn reconstruction algorithms that are robust to different environments (e.g., the different OAT image reconstruction settings) or invariant to such environments is highly valuable because it allows us to focus on what truly matters for the application at hand and discard what are considered spurious features. In this work, we explore the use of deep learning algorithms based on learning invariant and robust representations for the OAT inverse problem. In particular, we consider the application of the ANDMask scheme due to its easy adaptation to the OAT problem. Numerical experiments are conducted showing that when out-of-distribution generalization (against variations in parameters such as the location of the sensors) is imposed, there is no degradation of the performance and, in some cases, it is even possible to achieve improvements with respect to standard deep learning approaches where invariance robustness is not explicitly considered.

On the robustness of model-based algorithms for photoacoustic tomography: Comparison between time and frequency domains

For photoacoustic image reconstruction, certain parameters such as sensor positions and speed of sound have a major impact on the reconstruction process and must be carefully determined before data acquisition. Uncertainties in these parameters can lead to errors produced by a modeling mismatch, hindering the reconstruction process and severely affecting the resulting image quality. Therefore, in this work, we study how modeling errors arising from uncertainty in sensor locations affect the images obtained by matrix model-based reconstruction algorithms based on time domain and frequency domain models of the photoacoustic problem. The effects on the reconstruction performance with respect to the uncertainty in the knowledge of the sensors location are compared and analyzed both in a qualitative and quantitative fashion for both time and frequency models. Ultimately, our study shows that the frequency domain approach is more sensitive to this kind of modeling errors. These conclusions are supported by numerical experiments and a theoretical sensitivity analysis of the mathematical operator for the direct problem.

Seasonal Dynamics of Fleas (Siphonaptera: Pulicidae, Ceratophyllidae and Leptopsyllidae) on Oryctolagus cuniculus in a Meso-Mediterranean Area of Central Spain

Flea infestations of wild rabbits were examined monthly in central Spain in a meso-Mediterranean area for 5 yr. A total of 1,180 wild rabbits were trapped and 7,022 fleas were collected from them. Overall, the prevalence was 74.1% with a mean flea index of 5.95 fleas per rabbit. Four flea species were identified: Spilopsyllus cuniculi (Dale, 1878) was the most abundant species (accounting for 74.3% of fleas collected) followed by Xenopsylla cunicularis (Smit, 1957), Odontopsyllus quirosi (Gil Collado, 1934), and Nosopsyllus fasciatus (Bosc, 1800) (18.9, 6.7, and 0.1%, respectively). The highest prevalence was observed in S. cuniculi (48.6%) followed by X. cunicularis, O. quirosi, and N. fasciatus (34.3, 20.0, and 0.6%, respectively). Odontopsyllus quirosi and S. cuniculi were mainly collected from autumn to spring with the peak of infestation in winter, while X. cunicularis was mainly found from spring to autumn with maximum levels of infestation during the summer months. The relevance of these findings is discussed.

A method for the calibration of wideband ultrasonic sensors for optoacoustics

A method for calibration of ultrasonic sensors for optoacoustics that provides both frequency response and sensitivity is presented. In order to obtain the bandwidth and the frequency response of an uncalibrated sensor, a point source with broadband spectra generated by a laser-induced bubble on a copper wire submerged in water is employed. On the other hand, the sensitivity measurement relies on the spatial symmetry of the pressure pulse and on a calibrated transducer. Therefore, two sensors are employed to detect the pressure pulse at the same distance from the source. The symmetry of the acoustic field that arrives at both transducers is adjusted and verified by means of an optical interferometer that provides a null signal when the copper wire is placed at the right position. The method is tested on the characterization of a thin-film polymeric piezoelectric transducer with a cylindrical focused shape.

Generation of sub-microsecond quasi-unipolar pressure pulses

We present a method to generate sub-microsecond quasi-unipolar pressure pulses. Our approach is based on the laser irradiation of a thin copper wire submerged in water. The acoustic waveforms were recorded using two different, well characterized, wideband detection techniques: piezoelectric and optical interferometry. The results show that the irradiated target behaves as an omnidirectional source. Moreover, the peak pulse pressure linearly depends on the laser fluence and the source size. From the results, we propose an empirical equation for the spatial and temporal profile of the pressure pulse. The method has several advantages: ease of implementation, high repeatability, wide ultrasonic bandwidth and quasi-unipolar time profile. These features lead to potential applications of this acoustic source in ultrasonic characterization such as transducer systems, materials or passive devices.

[Urinary incontinence and lower urinary tract dysfunction prevalence in schoolchildren: risk factors]

Recently, many papers report an increase of pediatric lower urinary tract dysfunction (LUTD), which affects 10-15% of schoolchildren. Recent life style and dietary changes have been postulated as the cause of that high prevalence. There is a lack in epidemiological investigations about bowel and bladder dysfunctions and the risk factors. We aim to know the LUTD prevalence and the main risk factors. We carry out an observational and transversal investigation with a representative sample of our pediatric schoolchildren (N=1,069). We used a questionnaire about toilet training habits, social, familiar, and dietary data. We also used the PLUTSS (Pediatric Lower Urinary Tract Symptoms Score) questionnaire after validation of the Spanish version. The logistic regression analysis determined the main risk factors of DTUI. Results showed that boys get toilet trained later than girls (2.41 vs. 2.25) and the rate of incontinence is greater than girls when they start on the school. 31.9% of children remove their diapers to get into school. The prevalence was 15% for diurnal urinary incontinence and 12.2% nocturnal, DTUI 8.3%, constipation 20%, faecal incontinence 2.8%, ITUs 12.4%, retention habits 39.8%. 28.7% of children with DTUI refer psychological affectation. The main independent predictors were: male sex (OR 1.87), younger children (OR 0.78), forced toilet training (OR 2.14), constipation (OR 1.61) and holding habits (OR=3.87). This study showed a high prevalence of bladder in our pediatric population. Male gender, voiding postposition, early schooling or constipation were the main risk factors. The knowledge of the bladder and bowel dysfunction prevalence and the toilet training habits in our Community lets us to conclude school, family and primary care recommendations. This will let to prevent this so much prevalent disease.

[Video-assisted thoracoscopic treatment for two ports for idiopathic palmar and axillary hyperhidrosis in children]

JUSTIFICATION

Primary hyperhidrosis is a benign disease that consists in the excessive production of sweat, mainly in the hands, axillas and feet. It may to interfere with the social and work life of the sufferer. It affects up to 3% of the population. In Cuba there are no epidemiological studies on its prevalence. One of the treatment modalities is videothoracoscopic sympathicotomy.

OBJECTIVES

To describe the results of the videothoracoscopic sympathicotomy technique for two ports using apneic oxygenation to achieve lung collapse.

METHOD

Descriptive, retrospective study of 27 cases operated by primary hyperhidrosis in the period from May 2015 to June 2018. Demographic and clinical characteristics of operated patients, results of the endoscopic surgical technique, postoperative complications and satisfaction were described.

RESULTS

The 27 patients were adolescents with ages ranging from 11 to 19 years old, it was more frequent in the female sex. All patients had total solution of the symptoms in the intraoperative period, demonstrated by the cessation of sweat in the palms or axillas and by the verification of the increase of the palmar temperature in the monitor. No patient had intraoperative complications. Compensatory sweating occurred in four patients and one had intercostal neuritis. 100% of the patients were satisfied with the result at 30 days of treatment.

CONCLUSIONS

It is a safe technique, with few complications, high satisfaction with the results and feasible to perform in pediatric hospitals with basic resources of minimal access surgery.

[Varicoceles in adolescents and relationship with bmi: are varicoceles more frequent in tall thin men?]

OBJECTIVES

Varicocele is a dilatation of the venous pampiniform plexus considered the leading cause of correctible male infertility. Varicocele ethology remains controversial and there have been several studies which inform that varicoceles are found less frequently in obese adolescents but relationship between varicocele and body mass index (BMI) remains controversial yet.

SUBJECTS AND METHODS

To study the relationship between varicocele and body mass index in children population we review the patients treated for varicocele in our institution. We analyzed patients with varicocele surgical correction in our centre in the last 10 years. At our institution all patients were treated by Palomo technique. We analyzed: age, location and degree of varicocele, weight and height, surgical technique, appearance of reactive hydrocele or others complications, varicocele recurrence and reoperation. Our objective is to study the relationship between BMI and varicocele in adolescent boys.

RESULTS

We observed that varicocele in our series was found more frequently in taller patients and less frequently in obese patients (higher BMI).

CONCLUSIONS

Future studies will be needed to confirm that theory and to understand varicocele ethology but we consider that this fact is very useful because we are talking about a pathology with repercussion in fertility so we must be alert about it in adolescent population to correct it.

[Parent controled analgesia system in postoperative pain management in patients undergoing lip and cleft palate surgery]

OBJECTIVES

Craniofacial clefts surgery associates a painful postoperative pain whose management is complicated with conventional analgesia.

PATIENTS AND METHODS

A parent controlled analgesia system was implanted with a continuous perfusion of tramadol, ondansetron and metamizole adjusted by weight. Parents are allowed to administer additional boluses if they observe irritability. We compared the variables of the cleft patients operated before and after the implantation of the system in our center.

RESULTS

During 2016, 16 craniofacial clefts were operated (4 cheilorhinoplasties and 12 palatal clefts). No PCA (parent controlled analgesia) system was used. The average time of stay in PICU was 1.5 days. It took an average of 2.5 days to initiate tolerance. The mean of VAS (Visual Analogic Scale) was 3. 53% required major opioids (morphine, fentanyl) not being sufficient analgesia every 3 hours. During 2017, 7 palatal fissures and 4 cheilorhinoplasties were operated (11). Both of them were controlled by PCA. Patients with palatal cleft were admitted to the PICU with a total mean of 0.5 days. The beginning of tolerance was advanced to the first postoperative day. The VAS diminished to 0.5. Only one patient required opioids. 72% did not need to associate any type of analgesia.

CONCLUSIONS

The PCA system is a safe and risk-free insurance for analgesia of fissured patients with benefits such as: decrease in pain, stay in PICU, the need for analgesia and initiation of early tolerance.

Prediction of the presence of esophageal varices using spleen stiffness measurement by transient elastography in cirrhotic patients

BACKGROUND AND STUDY AIMS

Upper gastrointestinal endoscopy (UGE) is currently recommended in cirrhotic patients to detect the presence of esophageal varices (EV). Spleen stiffness measurement (SSM) with FibroScan has been used for this purpose, showing variable sensitivity (S) and specificity (Sp). The aim of this study was to evaluate the capability of SSM to detect the presence and size of EV in cirrhotic patients in comparison to other noninvasive modalities.

PATIENTS AND METHODS

Sixty-six patients with cirrhosis who had undergone UGE in the previous 6 months underwent SSM and liver stiffness measurement (LSM) using FibroScan. Biochemical parameters and ultrasonography data were also collected to calculate other noninvasive indexes.

RESULTS

Valid spleen stiffness measurements were obtained for 60 of the 66 patients initially included in the study (90.1%). In the multivariate analysis only splenomegaly and SSM were predictive of esophageal varices. SSM was the most accurate diagnostic tool, obtaining an area under the ROC curve of 0.8 for values below 48 KPascals, with S = 87%, Sp = 69%, and 76.7% of successfully diagnosed patients.

CONCLUSIONS

SSM with FibroScan was significantly higher for cirrhotic patients with EV. Our study suggests that spleen stiffness may be useful to identify cirrhotic patients at risk of having EV, although further studies are needed.

Spirocercosis in red fox (Vulpes vulpes) in a natural reserve located in a meso-Mediterranean area

Spirocerca lupi Rudolphi 1809 (Nematoda Spirocercidae) has an indirect cycle involving intermediate and paratenic hosts, having domestic or wild canids as the main definitive hosts. The most frequent pathology affecting dogs is a granulomatous tumor-like growth containing adults in the oesophagus and aorta. There are very few references about the presence of nodules in the stomach. There is scant information about the epidemiology of this disease in wild red foxes in meso-Mediterranean areas. In this work we report on the natural infection of wild red foxes by Spirocerca lupi and the damage produced in the stomach wall in an area where contact with other potential definitive hosts (canids) is very rare. From July 2015 to November 2016, 61 red foxes were sampled. 18.03% of the stomach walls examined had nodules containing Spirocerca lupi adults and eggs. The prevalence of infection was similar for young and adult groups (23.81 and 18.18%; χ2 = 0.25; df = 1; P = 0.6171) and it was higher in females than in males (25.81 versus 10.00%, χ² = 2.58; df = 1; P = 0.1082). The red fox population in the area seems to be well established judging from their age distribution and the fact that they could be captured all year round. It would appear that in the absence of other main definitive host S. lupi population is able to survive just parasitizing red foxes. Pathologic effects of this parasite on red foxes seems to show some differences related to domestic dogs. These results also indicates as predator control programs can maintain suitable host populations with reduced level of infection.

Endoscopic balloon dilatation in primary obstructive megaureter: Long-term results

BACKGROUND

Open neoureterocystostomy is the traditional surgical treatment for primary obstructive megaureter (POM). Endoscopic balloon dilation is a new minimally invasive alternative. It has been shown to be a safe and effective endoscopic procedure over short-term follow-up; however, few studies have shown its long-term efficacy.

OBJECTIVE

The aim of this study was to evaluate the long-term results and complications of balloon dilation for the treatment of primary obstructive megaureter in infants.

MATERIALS AND METHOD

A retrospective review was performed of patients with primary obstructive megaureter treated with balloon dilation. The diagnosis was made through ultrasonography, diuretic isotopic renogram, and voiding cystourethrogram (VCUG). The indications for surgery were: worsening hydronephrosis, renal function impairment, and recurrent urinary tract infections (UTI). All patients were followed 3 months after the endoscopic procedure with ultrasonography and MAG-3 renogram, and 6 months after surgery with VCUG and ultrasonography. Annual ultrasound and clinical follow-up were performed until present time.

RESULTS

Seven boys and six girls were treated (median age 9 months, range 2-24). Ten patients had a prenatal diagnosis of hydronephrosis, and the diagnoses was made after UTI in three patients. No intraoperative complications were observed. One double-J stent was replaced after endoscopic procedure for malpositioning, and four patients developed UTIs after surgery. All patients had non-obstructive MAG-3 diuretic renogram 6 months after surgery. The mean washout on the renogram and the ultrasound pelvic diameter showed pre-operative and postoperative statistical differences (Summary Table). All patients maintained their results without recurrence or any other complications in the long-term follow-up. The median follow-up was 10.3 years (range 4.7-12.2).

DISCUSION

In 2014, Aparicio et al. first described balloon dilation being used as a definitive treatment for primary obstructive megaureter in infants. Bujons et al. also presented 20 cases with a mean follow-up of 6.9 years. The current study is the largest to date, with a median follow-up of 10.2 years. It demonstrated the value of balloon dilation as a definitive treatment for POM. Despite these results, it was difficult to establish endoscopic balloon dilation as a definitive treatment for POM, due to the absence of long-term studies like the current one.

CONCLUSION

Balloon dilation can be a safe and effective endoscopic procedure for the treatment of primary obstructive megaureter in infants, and has shown good outcomes in long-term follow-up. More studies are needed to demonstrate these results.

Parametric modeling of wideband piezoelectric polymer sensors: Design for optoacoustic applications

In this work, we present a three-dimensional model for the design of wideband piezoelectric polymer sensors which includes the geometry and the properties of the transducer materials. The model uses FFT and numerical integration techniques in an explicit, semi-analytical approach. To validate the model, we made electrical and mechanical measurements on homemade sensors for optoacoustic applications. Each device was implemented using a polyvinylidene fluoride thin film piezoelectric polymer with a thickness of 25 μm. The sensors had detection areas in the range between 0.5 mm² and 35 mm² and were excited by acoustic pressure pulses of 5 ns (FWHM) from a source with a diameter around 10 μm. The experimental data obtained from the measurements agree well with the model results. We discuss the relative importance of the sensor design parameters for optoacoustic applications and we provide guidelines for the optimization of devices.

Modeling thin-film piezoelectric polymer ultrasonic sensors

This paper presents a model suitable to design and characterize broadband thin film sensors based on piezoelectric polymers. The aim is to describe adequately the sensor behavior, with a reasonable number of parameters and based on well-known physical equations. The mechanical variables are described by an acoustic transmission line. The electrical behavior is described by the quasi-static approximation, given the large difference between the velocities of propagation of the electrical and mechanical disturbances. The line parameters include the effects of the elastic and electrical properties of the material. The model was validated with measurements of a poly(vinylidene flouride) sensor designed for short-pulse detection. The model variables were calculated from the properties of the polymer at frequencies between 100 Hz and 30 MHz and at temperatures between 283 K and 313 K, a relevant range for applications in biology and medicine. The simulations agree very well with the experimental data, predicting satisfactorily the influence of temperature and the dielectric properties of the polymer on the behavior of the sensor. Conversely, the model allowed the calculation of the material dielectric properties from the measured response of the sensor, with good agreement with the published values.

Oral-facial-digital syndrome type I: surgical approach and a case report

PURPOSE

Oral-facial-digital (OFD) syndromes constitute a heterogeneous group of embrionary development disorders. There are at least 11 different forms, with a broad spectrum of clinical features, causing an important problem with the diagnosis. There are only a few reports in the recent literature, and there is no surgical technique described for its correction.

MATERIALS AND METHODS

We present a newborn female referred to the Cleft Lip and Palate Division of our hospital with facial dysmorphology; her mother was affected by an incomplete form of this syndrome. Genetic investigation showed a mutation not reported before in the literature. We present the clinical features and a new surgical approach for its correction.

RESULTS

OFD syndrome type I (OFD I) is characterised by several clinical features, including incomplete central upper lip cleft, bifid tongue, intraoral hamartomas, upper lip frenula and soft palate cleft. With this technique, we get a good aesthetic result.

CONCLUSION

OFD I is extremely infrequent and it is important to differentiate it from other forms of OFD. We want to emphasise the importance of performing a correct differential diagnosis in patients affected by palate cleft who have intraoral masses or feeding problems, to rule out incomplete forms of this syndrome. Surgical correction of the malformations associated with this syndrome is a challenge for the paediatric surgeon, because none of the previously reported techniques approach the reparation of this central labial defect.

Stereodynamics of the photodissociation of nitromethane at 193 nm: unravelling the dissociation mechanism

The photodissociation of nitromethane at 193 nm is reviewed in terms of new stereodynamical information provided by the measurement of the first four Dixon's bipolar moments, β0(2)(20), β0(0)(22), β0(2)(02), and β0(2)(22), using slice imaging. The measured speed-dependent β0(2)(20) (directly related with the spatial anisotropy parameter β) indicates that after one-photon absorption to the S3(2 (1)A″) state by an allowed perpendicular transition, two reaction pathways can compete with similar probability, a direct dissociation process yielding ground-state CH3 and NO2(1 (2)A2) radicals and a indirect dissociation through conical intersections in which NO2 radicals are formed in lower-lying electronic states. A particularly important result from our measurements is that the low recoil energy part of the methyl fragment translational energy distribution presents a contribution with parallel character, irrespective of the experimental conditions employed, that we attribute to parent cluster dissociation. Moreover, the positive values found for the β0(0)(22) bipolar moment indicates some propensity for the fragment's recoil velocity and angular momentum vectors to be parallel.

[Transepithelial phototherapeutic keratectomy to treat chronic laser in situ keratomileusis-flap macrostriae. A case review]

OBJECTIVE

To describe the use of transepithelial phototherapeutic keratecomy for the long-term treatment of post-laser in situ keratomileusis (LASIK) flap macrostriae.

METHOD

We present the case of a 22 year old male with visual loss in the left eye due to chronic flap macrostriae that was treated with transepithelial PTK.

RESULTS

Striae and haze were no longer visible, with a significant improvement of best corrected visual acuity. Refraction in the third month was +9.75-4.00×170°. A phakic intraocular lens was implanted one year later with an uncorrected visual acuity of 0.8.

CONCLUSIONS

PTK can solve chronic flap striae, but refraction outcome is unpredictable.

Photodissociation of pyrrole-ammonia clusters below 218 nm: quenching of statistical decomposition pathways under clustering conditions

The excited state hydrogen transfer (ESHT) reaction in pyrrole-ammonia clusters (PyH·(NH(3))(n), n = 2-5) at excitation wavelengths below 218 nm down to 199 nm, has been studied using a combination of velocity map imaging and non-resonant detection of the NH(4)(NH(3))(n-1) products. Special care has been taken to avoid evaporation of solvent molecules from the excited clusters by controlling the intensity of both the excitation and probing lasers. The high resolution translational energy distributions obtained are analyzed on the base of an impulsive mechanism for the hydrogen transfer, which mimics the direct N-H bond dissociation of the bare pyrrole. In spite of the low dissociation wavelengths attained (~200 nm) no evidence of hydrogen-loss statistical dynamics has been observed. The effects of clustering of pyrrole with ammonia molecules on the possible statistical decomposition channels of the bare pyrrole are discussed.

[Is experimental surgery necessary or essential in the training program of a pediatric surgeon?]

Many surgical procedures performed in pediatric surgery have a slow learning curve, the volume of patients and the existence of complex diseases that require extensive training and surgical skill, have taken our service to create a global training program of experimental surgery. This program based on the simulation and training invasive procedures in real anatomical models, aims to educate our residents in a global and efficiently way in order to obtain an improvement of technical training, and increased patient safety result of experience and expertise wined in the experimental animal. This paper presents the main features, objectives and results obtained with this training program and seeks to promote the incorporation of simulation programs in live animal as an essential part of the training of pediatric surgery resident.

Slice imaging and wave packet study of the photodissociation of CH3I in the blue edge of the A-band: evidence of reverse 3Q0 ← 1Q1 non-adiabatic dynamics

The photodissociation of CH(3)I in the blue edge (217-230 nm) of the A-band has been studied using a combination of slice imaging and resonance enhanced multiphoton ionization (REMPI) detection of the CH(3) fragment in the vibrational ground state (ν = 0). The profiles of the CH(3) (ν = 0) kinetic energy distributions and the photofragment anisotropies are interpreted in terms of the contribution of the excited surfaces involved in the photodissociation process, as well as the probability of non-adiabatic curve crossing between the (3)Q(0) and (1)Q(1) states. In the studied region, unlike in the central part of the A-band where absorption to the (3)Q(0) state dominates, the I((2)P(J)), with J = 1/2, 3/2, in correlation with CH(3) (ν = 0) kinetic energy distributions show clearly two contributions of different anisotropy, signature of the competing adiabatic and non-adiabatic dynamics, whose ratio strongly depends on the photolysis wavelength. The experimental results are compared with multisurface wave packet calculations carried out using the available ab initio potential energy surfaces, transition moments, and non-adiabatic couplings, employing a reduced dimensionality model. A good qualitative agreement is found between experiment and theory and both show evidence of reverse (3)Q(0)←(1)Q(1) non-adiabatic dynamics at the bluest excitation wavelengths both in the fragment kinetic energy and angular distributions.

Background subtraction in pulsed photoacoustics through neural-network processing

We report on the application of neural-network processing to pulsed photoacoustics for improving the detection limit by subtracting the window-heating-associated background. This technique was applied to the measurement of ethylene traces excited by a TEA (transverse electrical discharge in gas at atmospheric pressure) CO(2) laser. The signal contains a term that shows absorption saturation, characteristic of the absorbing gas, and another, generated by window heating, linearly dependent on laser energy. At low concentrations, normalization to laser energy is not possible owing to the different absorption mechanisms. To overcome this problem we relied on a neural-network filter, trained with experimentally obtained patterns, that subtracts the background and returns the sample concentration. This way, we reduced the detection limit to 20% of the previous limit obtained by reading the main resonance peak amplitude.

Evaluation of the quality of the water in El Hondo natural park located in the east of Spain

The purpose of the present work was to evaluate the quality of the water in El Hondo Park, an important wetland located in the east of Spain (province of Alicante) and included on the Ramsar List. The influence of the input of pollutants was assessed over a 14-month period in order to propose remedial action. Three different sources of waters were studied: irrigation water, brackish water and reservoir water. The irrigation water was found to have a high value of conductivity with high concentrations of Cl-, SO(4)2-, Na+ and K+ due to the influence of the brackish water. The concentration of organic matter given as CODT (total chemical oxygen demand) was found to be in the range of 70-600 mg/L of CODT, which was comparable to low-middle strength wastewater. A high concentration of Chlorophyll (a) was found in samples of reservoir water and the eutrophication of this water was thus observed. A high linear relationship was found among CODT, CODF (filtered COD) and BOD5; among electrical conductivity (E.C.), Cl-, SO4(-2), Na+, K+, Ca2+ and Mg2+ and among pH, CO3H- and CO(3)2- in all the samples evaluated. Taking this fact into consideration, a simplified water quality index (WQI) was calculated. Using this parameter, the quality of the water from different sources and its variation during the period evaluated was determined to be at a maximum during the months of December to February, which coincided with the period of high precipitations and low temperature. The highest values of this parameter were found in the samples corresponding to the reservoir water while the lowest values were found in the samples of the brackish water. By determination of the WQI, the influence of the brackish water on the quality of water for irrigation and reservoir waters was confirmed.

Estudio prospectivo sobre la utilidad de la ecografía de control tras la realización de pruebas invasivas hepáticas: biopsia hepática y punción aspiración con aguja fina (PAAF)

OBJECTIVE

To determine the need to perform ultrasound scans to all patients after liver biopsy or fine-needle aspiration (FNA) in order to detect complications with or without symptoms.

MATERIAL AND METHODS

After liver biopsy or FNA using a regular protocol the patient is observed for 24 hours at the hospital, and all patients undergo an abdominal sonography at that time even in the absence of evident complications.

RESULTS

298 liver biopsies and 98 FNAs were performed. There were complications in 37 patients (9.34%): 36 (9.09%) were minor complications such as pain, vasovagal episodes, or small bleeding, and 1 (0.25%) was a major complication with severe hemorrhage. Only 1 out of all 396 procedures had a complication detected by ultrasounds (intrahepatic hematoma) while the patient was asymptomatic.

CONCLUSIONS

The low incidence of complications occurring without symptoms, and their favorable course suggest that routine ultrasonography is not necessary after these techniques, and that it should be only performed when a complication is suspected.

[Nosocomial infection by multiresistant pathogens during one year in a secondary hospital: clinical an epidemiological analysis]

BACKGROUND

Currently growing medical and social significance of nosocomial infection by multiresistant pathogens (NIMP) prompted us to establish its incidence, nosology, presenting forms in admission areas, and mortality in a secondary hospital, Lleida (Spain).

METHOD

For that purpose, we analyzed the first year experience of a unit for the control of nosocomial infection (NI) created in our hospital. From January to December 2000, 79 patients with a NIMP admitted to the University Hospital Arnau de Vilanova entered in this prospective, descriptive study.

RESULTS

The overall annual incidence of NIMP was 4.0 per 103 patients admitted. Acinetobacter baumannii showed the highest individual rate of incidence, particularly, at the Intensive Care Unit (15.4 per 103 patients admitted; p < 0.001). By nosologies, infection prevailed over colonization (69.6% vs 30.4%; p < 0.001). Mean hospital stay length increased in colonized patients (38.9 days). Finally, overall mortality was high (29.1%); again, A. baumannii was the agent most frequently detected in death cases (66.6%; p < 0.001).

CONCLUSIONS

Surveillance and control measures are required for the prevention of NIMP. Incidence studies how this, can be useful to create a database to establish the distribution and occurrence of NI, including the detection of multiresistant pathogen outbreaks.

Prevention of de novo hepatitis B infection in liver allograft recipients with previous hepatitis B infection or hepatitis B vaccination

OBJECTIVES

To assess de novo hepatitis B virus (HBV) transmission from liver donors with HBV serum markers (HBM) to their recipients and the need for HBV vaccination before liver transplantation.

METHODS

A total of 108 orthotopic liver transplantations for nonviral disease and the risk of developing de novo hepatitis B based on HBMs before transplantation have been studied. Of the 108 patients, 94 met the study criteria and were divided into two groups: 27 who had HBMs before transplantation (from past infection or by previous vaccination) and 67 who had no HBM. Development of de novo hepatitis B was determined by analytical, serological, and histological parameters.

RESULTS

No case (0%) of de novo hepatitis B was detected in the pretransplantation HBM group, whereas there were 10 cases (14.5%) in the other group (p < 0.005).

CONCLUSIONS

The presence of pretransplantation HBM in liver transplant recipients protects these patients against the development of de novo hepatitis B. This is especially important considering that there is a high prevalence of donors with positive hepatitis B core antibody (especially in some countries), and that these donors transmit HBV infection to recipients without HBM in a significant number of cases. Thus, vaccination against HBV in patients who are candidates for liver transplantation is fundamental to avoid cases of de novo hepatitis B.

Myeloid mixed chimerism is associated with relapse in bcr-abl positive patients after unmanipulated allogeneic bone marrow transplantation for chronic myelogenous leukemia

BACKGROUND AND OBJECTIVE

Although bcr-abl polymerase chain reaction (PCR) positivity after bone marrow transplantation (BMT) for chronic myelogenous leukemia (CML) is significantly related to relapse, the predictive value of the assay is not very high and therefore most investigators consider that qualitative RT-PCR data alone are too imprecise to enable clinical decisions to be taken in individual cases. To define the clinical outcome of bcr-abl positive patients after unmanipulated BMT better, we sought the origin of hematopoiesis and traced its evolution over time.

DESIGN AND METHODS

Forty-nine patients received allogeneic BMT for CML (39 in chronic phase and 10 in accelerated phase/blast crisis). Median follow-up was 61 months (range 4-92). mRNA and DNA were used to assess bcr-abl and chimerism status respectively. Quantitative VNTR-PCR on total cells and lymphoid or myeloid population allowed us to assign and measure the origin of hematopoiesis.

RESULTS

Both bcr-abl positivity and the presence of mixed chimerism (MC) were significantly associated with relapse (p = 0.0009 and p < 0.0001 respectively). Relapse was observed in one of 39 patients with complete donor chimerism and in 6 of 9 patients with MC. These six cases showed increasing levels of host hemopoiesis and bcr-abl positivity in the CD15-positive population prior to relapse. The other three cases had decreasing or stable low-level MC which was restricted to the T-cells as well as bcr-abl negativity.

INTERPRETATION AND CONCLUSIONS

Whereas the simple detection of bcr-abl fails to identify patients who will relapse with certainty, the assessment of MC by VNTR-PCR does identify patients headed to relapse. Confirmation of myeloid involvement and increasing levels over time further elucidates the clinical outcome of bcr-abl positive patients after BMT.

Increasing mixed haematopoietic chimaerism after BMT with total depletion of CD4+ and partial depletion of CD8+ lymphocytes is associated with a higher incidence of relapse

In this study we analysed the incidence and clinical impact of the persistence of host haemopoiesis (mixed chimaerism, MC) after allogeneic BMT in 35 consecutive patients with haematologic malignancies using a total CD4+ cell-depleted graft with an adjusted dose of CD8+ cells (1x10(8)/kg). Chimaerism was assessed by PCR amplification of VNTRs in 30 evaluable patients: 19 non-CML and 11 CML cases which were also evaluated for the BCR-ABL transcript by RT-PCR. All but one had complete engraftment with a donor profile early post-BMT. At the end of the study period, 12 of 30 patients displayed MC (40%). The overall disease-free survival for MC patients was clearly unfavourable when compared to those who exhibited a donor profile (24.7% vs. 100%, P = 0.005). However, we found that only two of five patients with MC in the non-CML group relapsed, whereas a clear correlation could be made between MC and relapse in CML (seven showed MC, preceding cytogenetic or haematological relapse in six of them, which displayed a prior BCR-ABL mRNA positivity). In addition, a quantitative-PCR approach enabled us to demonstrate that increasing amounts of MC are invariably associated with subsequent relapse, whereas a low stable level of host or complete donor haemopoiesis is consistent with clinical complete remission. Although these results suggest that the clinical impact of MC may depend on the underlying disease, it is compatible with the concept that the graft-versus-leukaemia effect against CML is mainly exerted by donor CD4+ lymphocytes. Elimination of this cellular subset may be responsible for the inability of the graft to prevent a progressive increase in the tumor cell burden.

[Regression of left ventricular hypertrophy in hypertensive patients]

Left ventricular hypertrophy associated with systemic hypertension differs from left ventricular hypertrophy initiated by other pressure overload diseases. Its development depends not only of hemodynamics aspects but of biochemical factors. Many studies have demonstrated a close link between left ventricular hypertrophy and cardiovascular morbidity and mortality. For that reason the idea of reversal of left ventricular hypertrophy has been a goal of the antihypertensive treatment. From the literature review has been established that the most classes of antihypertensive medications reduce the left ventricular mass, though there is a variation in required duration of treatment. At this point the angiotensin converting enzyme inhibitors, probably because a double effect: hypotensive and blockers of the trophic stimulus of angiotensin II, seemed to be the most potent for reducing the left ventricular mass. Still we don't know if reversal of left ventricular hypertrophy, by the antihypertensive treatment, reduce independently the cardiovascular risk.

[Pharmacologic activity of the aqueous wood extract from Quassia amara (Simarubaceae) on albino rats and mice]

All the assays were done with an aqueous preparation of dry wood from Quassia amara (Simarubaceae). For the hippocratic assay, 12 female SDN rats were used, with an average weight of 144 g and separated in three groups of four individuals each. The dose used were 500 mg/kg and 1,000 mg/kg and the control group received 0.5 ml of distilled water. The extract administration and the observation of the animals were done daily during nine days. Acute toxicity of the preparation was studied with 25 male NGP mice with an average weight of 20.13 g, in groups of five individuals per dose. The oral administration was carry out with the following doses: 250, 500, 750 and 1,000 mg/kg, the control group received 0.5 ml of distilled water. No sign of acute toxicity was observed at any dose. For the toxicity analysis via intraperitoneal injection 15 male NGP mice were assigned to five groups (5 animals each) with doses of 500 and 1,000 mg/kg and a control group with 0.5 ml of distilled water. The group with the dose of 500 mg/kg, presented acute toxicity signs with a 24 hr recovery, and the 1,000 mg/kg dose was lethal to a 100% within 24 hr. The measuring of the peristaltic activity (movement of the intestinal content) were performed on 30 NGP male mice with an average weight of 22 g assigned to three groups of ten individuals each. One dose of 500 mg/kg and 1,000 mg/kg were orally administrated to each experimental group and 0.5 ml of distilled water to the control group. The marker used was activated carbon, orally supplied to every mice 30 min after the administration of the aqueous extract. The animals are decapitated and the measurement of the carbon motion in the small intestine was done after 30 min. Both dose increased the intestinal movement compared to the control group, but only the 1,000 mg/kg dose showed a statistically significant difference (p < or = 0.05).

[Cardiovascular effects of aqueous extracts of the leaves of Clusia coclensis (Guttiferae)]

Aqueous extracts of the leaves of Clusia coclensis, (Guttiferae) injected intravenously to 42 normal Sprague-Dawley rats and to 42 Spontaneous Hypertensive rats, in 7 different doses, induced a rapid and transitory decrease in blood pressure and heart frequency. The magnitude of blood pressure decrease was dose-dependent. The effect was statistically significant (p < or = 0.01), probably due to sympathetic stimuli.