Clinical features and genetic biomarkers associated with different phenotypes of systemic lupus erythematosus in Paraguayan patients.

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by a heterogeneous clinical picture that makes the diagnosis and follow-up of these patients difficult. This study aimed to identify correlations between clinical, immunological, and genetic biomarkers and clinical manifestations in SLE. A retrospective study of data from medical records and immunological and genetic studies of SLE patients in Paraguay was carried out. A descriptive analysis was performed based on the type of variable. Human leukocyte antigen (HLA) allele frequencies (DPA1, DPB1, DQA1, DQB1, and DRB1) were calculated, and univariate logistic regression analyses were performed between each of the explanatory variables and the presence or absence of each phenotype. Odds ratios, 95% confidence intervals, and p values were recorded. Associations with p<0.05 were considered statistically significant. 104 SLE patients were included: 86% were female, with a mean age of 32.80±10.36 years. An association was identified between anti-double stranded DNA (anti-dsDNA) and the presence of the renal phenotype and between anti-dsDNA and the absence of the joint and hematological phenotypes. Immunoglobulin M isotype rheumatoid factor was associated with the absence of a renal phenotype. HLA-DQB1*02:02 and HLA-DRB1*07:01 were associated with the cutaneous phenotype. An association was identified between age at disease onset over 30 years and the presence of the joint phenotype. No other associations were identified. Potential clinical, immunological, and genetic biomarkers of phenotypes have been identified in SLE Paraguayan patients.

Multi-Class Cost-Constrained Random Coding for Correlated Sources over the Multiple-Access Channel.

This paper studies a generalized version of multi-class cost-constrained random-coding ensemble with multiple auxiliary costs for the transmission of N correlated sources over an N-user multiple-access channel. For each user, the set of messages is partitioned into classes and codebooks are generated according to a distribution depending on the class index of the source message and under the constraint that the codewords satisfy a set of cost functions. Proper choices of the cost functions recover different coding schemes including message-dependent and message-independent versions of independent and identically distributed, independent conditionally distributed, constant-composition and conditional constant composition ensembles. The transmissibility region of the scheme is related to the Cover-El Gamal-Salehi region. A related family of correlated-source Gallager source exponent functions is also studied. The achievable exponents are compared for correlated and independent sources, both numerically and analytically.

Nearest Neighbor Decoding and Pilot-Aided Channel Estimation for Fading Channels.

We study the information rates of noncoherent, stationary, Gaussian, and multiple-input multiple-output (MIMO) flat-fading channels that are achievable with nearest neighbor decoding and pilot-aided channel estimation. In particular, we investigate the behavior of these achievable rates in the limit as the signal-to-noise ratio (SNR) tends to infinity by analyzing the capacity pre-log, which is defined as the limiting ratio of the capacity to the logarithm of the SNR as the SNR tends to infinity. We demonstrate that a scheme estimating the channel using pilot symbols and detecting the message using nearest neighbor decoding (while assuming that the channel estimation is perfect) essentially achieves the capacity pre-log of noncoherent multiple-input single-output flat-fading channels, and it essentially achieves the best so far known lower bound on the capacity pre-log of noncoherent MIMO flat-fading channels. Extending the analysis to fading multiple-access channels reveals interesting relationships between the number of antennas and Doppler bandwidth in the comparative performance of joint transmission and time division multiple-access.

Unifocal and unilateral pigmented paravenous retinochoroidal atrophy.

Paravenous pigmented chorioretinal atrophy (PPRCA) is a generally multifocal, bilateral and symmetric rare entity associated with autoimmune diseases and other ocular complications. We present the clinical case of a patient with rheumatoid arthritis who attended for pain of several days. He presented decreased visual acuity of the left eye (LE), nodular scleritis and chorioretinal atrophy with pigment accumulation in bone spicules in the inferior temporal vascular arcade and lamellar macular hole (AML). The right eye shows no alterations. LE autofluorescence (AF) shows a hypoautofluorescence lesion with defined edges. Fluorescein angiography (FAG) shows hyperfluorescence consistent with retinal pigmentary epithelial degeneration and blockage in pigment areas. The visual field (VC) reveals a defect in the superior hemifield. This case describes an atypical unifocal and unilateral PPRCA. This variant must be known to make a correct differential diagnosis, as well as to provide adequate prognostic information.

Glistening on intraocular lenses: A review.

The glistening in intraocular lenses (IOLs) is a phenomenon in which tiny water-filled microvacuoles (MVs) form within the IOL material, causing light to scatter and create a sparkling or shimmering effect. The presence of glistening is common in many types of IOL materials and models and has been extensively studied in recent years to determine its incidence, risk factors, evolution, and possible clinical relevance. Classically, it has been studied in vitro in the laboratory or by means of photography obtained with a slit lamp, but these were techniques that required either specific technology or an expert explorer, complex image processing, and required a lot of time. In recent years, proposals based on the Scheimpflug camera and optical coherence tomography have emerged to try to simplify the analysis of glistening in IOLs. It has been described that the manufacturing process, the hydrophobic acrylic material, or the time since surgery are risk factors for the appearance of glistening. In addition, many issues related to this phenomenon are still unknown, such as not knowing from what number of points or their size they may have relevance to visual function since different optical phenomena related to glistening have been described on the IOLs.

[Functional improvement in frail older adults through the Vivifrail exercise program, during two years of pandemic]. / Mejora funcional en personas mayores frágiles mediante el programa de ejercicios Vivifrail, durante dos años de pandemia.

BACKGROUND AND OBJECTIVE: Physical exercise increases functional capacity in older adults, helping to prevent or delay dependence. This study evaluates the impact of a multicomponent physical exercise intervention based on the Vivifrail program, conducted in a primary care center over two years coinciding with the COVID pandemic. SUBJECTS AND METHODS: Descriptive longitudinal design with before-after comparison without control group. Participants were older than 65 years old with functional impairment measured by execution test, enrolled in the El Palo Health Center, Málaga. The intervention consists of two weekly group sessions of physical exercise guided by a monitor, according to the Vivifrail program. VARIABLES: Barthel Index, Gait Speed, Vivifrail Category, Quality of Life (EuroQol 5-D [EQ-5D]), use of walking aids, number of falls in the previous year. MEASUREMENTS: baseline, second (one year) and final (two years). Analysis of the Kruskal-Wallis test, significance level 0.05. RESULTS: Twenty patients were evaluated. Between the first and second evaluation, we observed a significant modification in the use of walking aids (p 0.01) and Vivifrail categories: from an initial B category, 50% remained, 25% moved to A, 16.7% to C2 and 8.3% to D (p 0.048). In the analysis of the baseline-final evaluation, we found a statistically significant improvement in quality of life measured by EQ-5D (mean increase of 24 points in today's quality of life measurement, EQ-5D thermometer, with 95% CI (9.6-38.3), p 0.004) and Vivifrail category (n=10) with 60% remaining in category B and 40% moving to D (autonomous) (p<0.0001). There was a trend towards improvement in gait speed, daily walking time, and number of falls, but without reaching statistical significance. CONCLUSIONS: Multicomponent physical exercise improves perceived quality of life measured by EQ-5D and leads to a trend towards improvement in functional capacity, mood, and number of falls.

Assessment of the biometric modifications of the eye in LASIK during suction.

PURPOSE: To study the biometric modifications of the eyeball during suction in Laser assisted in Situ Keratomileusis (LASIK). METHODS: Observational and cross-sectional study. We studied 43 patients who underwent surgery for myopia and myopic astigmatism. Mean age was 38.3 ±â€¯11.5 years, and 19 were female (44.2%). Conventional LASIK surgery with a manual microkeratome was performed. Before and during the suction maneuvre the following parameters were measured using an 11 Mhz biometric probe: aqueous depth (AQD), lens thickness (LT), vitreous cavity length (VCL) and axial length (AXL). Paired t-test was used to compare the biometric measurements before and during suction. RESULTS: The mean spherical equivalent refractive error was -4.5 ±â€¯2.3 diopters. During suction, the AQD did not change significantly (p = 0.231). However, AXL and VCL increased by 0.12 mm and 0.22 mm respectively (p = 0.039 and <0.01) and LT decreased by 0.20 mm (p < 0.01). AXL increased in 42% of the eyes and decreased in 16%, VCL increased in 70% of the eyes and decreased in 9%, and the LT was reduced in 67% of the eyes. CONCLUSIONS: Suction maneuvres during LASIK surgery produce changes of little magnitude in the eye globe, mainly a decrease in LT and an increase in VCL and AXL. Therefore, these modifications are expected to produce minimal anatomic alterations.

[Synchronous adenocarcinoma and lymphoepithelioma-like carcinoma in the stomach: a case presentation and literature review]. / Adenocarcinoma y carcinoma tipo linfoepitelioma sincrónico en estómago: presentación de un caso y revisión de la literatura.

Gastric cancer is one of the main causes of death in the world. In Venezuela, gastric tumors represent 37% of all malignant tumors of the digestive system, but only 1,6% to 3,1% of these cases are lymphoepithelioma-like carcinoma. Synchronous neoplastic lesions are also rare. The clinical case presented herein, a man with two synchronous tumor lesions, is the first of its kind in this country. Despite their incipient aspect, the histologic study reported two malignant tumors of epithelial origin: well-differentiated adenocarcinoma and lymphoepithelioma-like carcinoma.

Agreement between optical coherence and Scheimpflug tomography: Vault measurements and reproducibility after implantable collamer lens implantation.

PURPOSE: To evaluate the agreement between Scheimpflug tomography (Pentacam, Oculus) and anterior segment optical coherence tomography (AS-OCT, RTVue 100, Optovue) as well as the reproducibility of each technique in assessing the lens-ICL distance (vault) after implantable collamer lens (ICL) implantation. METHODS: The vault was measured manually with Scheimpflug tomography and AS-OCT. Intraclass correlation coefficients (ICC) and Bland-Altman plots were used to determine the reproducibility of measurements and the agreement between them. Multivariate regression analysis was performed to identify predictors of differences in vault measurements between devices. RESULTS: 80 eyes of 46 ICL patients were analyzed. Mean patient age was 33.8±7.4 years (range, 21 to 51), and 27 (59%) were women. The preoperative spherical equivalent refraction ranged from -26 to 8.5 diopters (D). The mean vault measured by AS-OCT was 558.8±240.2µm (range, 162 - 1220) vs. 430.1±215.3µm (range, 0 to 1070) by Pentacam. AS-OCT yielded vault values, on average, 128.1±64.6µm higher than the Pentacam (range, -22 to 293µm). The ICC values for consistency and absolute agreement were 0.960 and 0.928, respectively. Reproducibility of vault measurements was excellent for both devices (ICC≥0.946). Four parameters-vault, pupil diameter (PD), PD differences between devices, and preoperative spherical equivalent refraction-were significant predictors of differences in vault measurements (adjusted-R2=0.412; P<0.001). CONCLUSIONS: Agreement between AS-OCT and Pentacam for vault measurement was good. Vaults were higher when measured by AS-OCT. These differences are clinically relevant, and therefore these devices cannot be used interchangeably to measure vault.

Assessment of changes in the macula and optic nerve head using optical coherence tomography in patients with attention deficit hyperactivity disorder. / Evaluación de los cambios en la mácula y en el nervio óptico mediante tomografía de coherencia óptica en pacientes con trastorno por déficit de atención e hiperactividad.

INTRODUCTION: To assess if there are any differences in macular and papillary thickness using optical coherence tomography (OCT) in patients with attention deficit hyperactivity disorder (ADHD) compared with a control group, including if there are differences between ADHD patients with and without treatment. METHODS: Prospective observational study including 92 eyes of 46 patients divided into 2 groups: 46 eyes of 23 patients with ADHD, and a control group of 46 eyes of 23 healthy patients. The group of patients with ADHD was subdivided into those on treatment with methylphenidate (n=28) and those not on treatment (n=18). The macular thickness, the ganglion cell complex (GCC), and the retinal nerve fibre layer (RNFL) at the papillary level were measured in 12 sectors. RESULTS: A lower central macular thickness was observed in the ADHD patients than in the controls (257.4±20µm versus 267.5±20µm, P=.013), with no differences observed in the GCC (P=.566), or in the RNFL (P=.095). There were no differences in the patients with ADHD with and without treatment, as regards macular thickness and the GCC (P=.160 and P=.375 respectively), but a lower foveal thickness (P=.018) and RNFL in 5/12 sectors at the papillary level (P=.033) were observed in those without treatment. CONCLUSIONS: A lower macular thickness was observed in patients with ADHD than in controls. In addition, patients with ADHD without treatment had a lower thickness of the fovea and RNFL than those patients on treatment.

Head-space gas chromatography coupled to mass spectrometry for the assessment of the contamination of mayonnaise by yeasts.

Head-space (HS) gas chromatography (GC) coupled to mass spectrometry (MS) is proposed for the assessment of the contamination of mayonnaise as an alternative to plate counting, which is the technique commonly used for evaluating microbial contamination. More specifically, this method was applied in the detection of Candida metapsilosis and Zygosaccharomyces bailii, both of great importance in term of food spoilage since they are resistant to many of the common methods of food preservation. Different chemometric models were investigated using the data obtained by GC-MS (m/z profile, area of the chromatographic peaks and entire chromatographic profile), in order to obtain the highest classification success. The best results were obtained using the chromatographic profile (success rate of 92%). Contaminated samples could also be classified according to the concentration of yeast, obtaining a success rate of 87.5%. Finally, a chemometric model was constructed in an attempt to differentiate between strains.

Efficacy of combinations of colistin with other antimicrobials involves membrane fluidity and efflux machinery.

OBJECTIVE: Despite its use was abandoned several decades ago, the polycationic peptide colistin has become the last hope to treat severe infections caused by multidrug-resistant Gram-negative bacteria. Thus, the development of colistin resistance may seriously compromise the efficacy of treatment. Moreover, colistin has high toxicity being dose dependent. A potentially effective strategy to avoid resistance may be to combine colistin with other antimicrobials. This may help in the rescue of old antimicrobials and in reducing toxic undesired effects. METHODS: Antimicrobial susceptibility determination, efflux machinery function measurements in different conditions and measurement of inhibition of the extrusion by colistin were performed. Moreover, modifications of anisotropy of the membranes by using fluorescent dyes was accomplished. RESULTS: Sub-inhibitory concentrations of colistin have a synergistic effect with several antimicrobials that act intracellularly (targeting protein synthesis and DNA replication). This effect was demonstrated through the uptake increases of acridine orange. in Pseudomonas aeruginosa, Escherichia coli and Acinetobacter baumanii but also in an intrinsically colistin-resistant species as Serratia marcescens. Measurements of the anisotropy of bacterial membranes, as a measure of membrane fluidity, showed significant changes indicative of colistin activity. CONCLUSION: The alterations in the cellular efflux machinery that resulted in higher intracellular concentrations of acridine orange, and likely of other antimicrobials combined with data of membrane fluidity and measured synergism in vitro allow us to envisage the use of these combinations to fight infections caused by multidrug-resistant bacteria.

Pseudoexfoliation signs in the anterior segment assessed by optical coherence tomography and Scheimpflug device. / Evaluación de los signos de la pseudoexfoliación en el segmento anterior mediante tomografía de coherencia óptica y cámara de Scheimpflug.

OBJECTIVE: To evaluate different anterior segment parameters in eyes with pseudoexfoliation (PSX), fellow eyes, and controls using optical coherence tomography and a Scheimpflug imaging system. METHODS: Three groups were studied: 44 eyes of 44 patients with PSX, 30 clinically unaffected fellow eyes, and 148 eyes of 148 healthy controls. The anterior chamber depth and volume, corneal volume and thickness, pupil diameter and corneal densitometry were measured using a Scheimpflug imaging system (Pentacam, Oculus Inc.; Wetzlar, Germany). The angle width, the length and area of the trabecular meshwork, and the iris thickness were measured using an optical coherence tomography RTVue 100 device (Optovue, Fremont, CA, USA). The presence of PSX deposits was also assessed by OCT. RESULTS: There were no differences in the anterior chamber volume or depth in the corneal volume or central thickness (P≥.228). The corneal densitometry was similar between PSX and fellow eyes; however it was greater than in the control group (P<.001). As regards the parameters measured by OCT, there were no differences in the angle width or in the trabecular meshwork size between the 3 groups; however, the iris was thinner in controls (P=.005). In all patients the PSX deposits were correctly visualised by OCT after the identification by biomicroscopy. CONCLUSIONS: There were no differences in the anterior segment biometric measurements between patients with PSX and controls, although the corneal densitometry and iris thickness were greater in the PSX and fellow eyes groups.

Remifentanil: A help in topical strabismus surgery. / Remifentanilo: una ayuda en la cirugía tópica del estrabismo.

OBJECTIVE: To analyze the analgesic effect of remifentanil, side effects and complications in topical strabismus surgery. To study the results of strabismus surgery with this type of anesthesia. MATERIAL AND METHOD: Retrospective descriptive study. We included 39 patients undergoing strabismus surgery with topical anesthesia and analgesia-based sedation with remifentanil. The data of the anesthetic and surgical technique, surgical results and stability of the deviation angle were analyzed. RESULTS: Thirty nine patients (54% women) were included, the average age was 37,4years old. The mean follow-up was 24,5months. The preoperative diagnoses were exotropia (21 patients), esotropia (12), paresis strabismus (4) and Duane's Syndrome (2). 15% patients had preoperative diplopia and 13 had received previous treatments. The dose range of remifentanil used was 0.05 to 0.2µg/kg/min. The side effects presented were 2 cases of vomit and one of bad collaboration during the intraoperative adjustment, one of the patient reported pain and one case of thoracic rigidity was reported. 79% of the patients obtained a good surgical result and 82% reported being satisfied with the results. The reintervention rate was 5%. CONCLUSIONS: Analgesia-based sedation with remifentanil is an useful complement to topical strabismus surgery because it reduces pain during surgery and allows the patient to collaborate during intraoperative adjustment due to its pharmacokinetic characteristics.

PCR Conditions for 16S Primers for Analysis of Microbes in the Colon of Rats.

The study of the composition of the intestinal flora is important to the health of the host, playing a key role in maintaining intestinal homeostasis and the evolution of the immune system. For these studies, various universal primers of the 16S rDNA gene are used in microbial taxonomy. Here, we report an evaluation of 5 universal primers to explore the presence of microbial DNA in colon biopsies preserved in RNAlater solution. The DNA extracted was used for the amplification of PCR products containing the variable (V) regions of the microbial 16S rDNA gene. The PCR products were studied by restriction fragment length polymorphism (RFLP) analysis and DNA sequence, whose percent of homology with microbial sequences reported in GenBank was verified using bioinformatics tools. The presence of microbes in the colon of rats was quantified by the quantitative PCR (qPCR) technique. We obtained microbial DNA from rat, useful for PCR analysis with the universal primers for the bacteria 16S rDNA. The sequences of PCR products obtained from a colon biopsy of the animal showed homology with the classes bacilli (Lactobacillus spp) and proteobacteria, normally represented in the colon of rats. The proposed methodology allowed the attainment of DNA of bacteria with the quality and integrity for use in qPCR, sequencing, and PCR-RFLP analysis. The selected universal primers provided knowledge of the abundance of microorganisms and the formation of a preliminary test of bacterial diversity in rat colon biopsies.

[Prenatal screening of congenital heart defects in population at low risk of congenital defects. A reality today]. / Cribado prenatal de cardiopatías congénitas en población de bajo riesgo de defectos congénitos. Una realidad en la actualidad.

INTRODUCTION: We propose to demonstrate that it is possible to implement a valid (diagnostic sensitivity for major cardiac malformations 90%), and universal (applied to over 90% of pregnant women), prenatal screening method for congenital heart defects. MATERIALS AND METHODS: Prospective study. A total of 12478 pregnant women were evaluated between January 2008 and December 2010. Congenital heart diseases were screened using fetal extended basic echocardiography (cardiac ultrasound). RESULTS: The prevalence of birth defects in general and congenital heart disease was 2.5% (2.2-2.7%) and 0.9% (0.7-1%) respectively. Congenital heart disease had a higher rate of association with other structural abnormalities with 11.5% (5.6-17.4%), 21% for major congenital heart disease (9.9-32%), and chromosomal abnormalities of 15.9% (9.1-22.7%), with 32.6% for major congenital heart disease (19.8-45.3%). A fetal cardiac ultrasound assessment was performed on 99.2% of pregnant women. The fetal echocardiography is useful for the diagnosis of congenital heart disease in general, and major congenital heart disease, with a sensitivity of 42.8% (33.5-52.5%) and 90.4% (78.9-96.8%), respectively, and a specificity for both of 99.9% (99.8-99.9%). CONCLUSIONS: It is possible to perform a valid prenatal and universal screening of major congenital heart disease.

4-dimethylamino-3',4'-dimethoxychalcone downregulates iNOS expression and exerts anti-inflammatory effects.

Reactive oxygen and nitrogen species contribute to the pathophysiology of inflammatory conditions. We have studied the effects of a novel superoxide scavenger, 4-dimethylamino-3', 4'-dimethoxychalcone (CH11) in macrophages and in vivo. CH11 has been shown to inhibit the chemiluminescence induced by zymosan in mouse peritoneal macrophages and the cytotoxic effects of superoxide. In the same cells, the modulation by superoxide of nitric oxide (NO) production in response to zymosan was investigated. CH11 was more effective than the membrane-permeable scavenger Tiron for inhibition of inducible nitric oxide synthase (iNOS) protein expression and nitrite production. We have shown that CH11 inhibited chemiluminescence in vivo, as well as cell migration, and eicosanoid and tumor necrosis factor-alpha (TNF-alpha) levels in the mouse air pouch injected with zymosan. This chalcone derivative also exerted anti-inflammatory effects in the carrageenan paw oedema.

Novel anti-inflammatory chalcone derivatives inhibit the induction of nitric oxide synthase and cyclooxygenase-2 in mouse peritoneal macrophages.

In a previous work, we tested a series of chalcone derivatives as possible anti-inflammatory compounds. We now investigate the effects of three of those compounds, CHI, CH8 and CH12, on nitric oxide and prostanoid generation in mouse peritoneal macrophages stimulated with lipopolysaccharide and in the mouse air pouch injected with zymosan, where they showed a dose-dependent inhibition with inhibitory concentration 50% values in the microM range. This effect was not the consequence of a direct inhibitory action on enzyme activities. Our results demonstrated that chalcone derivatives inhibited de novo inducible nitric oxide synthase and cyclooxygenase-2 synthesis, being a novel therapeutic approach for inflammatory diseases.

Treatment of congenital Chagas' disease diagnosed and followed up by the polymerase chain reaction.

In 1991 and 1992, a prenatal screening of Trypanosoma cruzi infection was carried out using ELISA and indirect immunofluorescence techniques. A total of 840 blood samples from pregnant women, obtained at the Maternity Ward of the Hospital de Clínicas, National University of Asunción (Asunción, Paraguay), and 1,022 samples from the Regional Hospital of the San Pedro Department of Paraguay were examined. It was observed that 7.7% and 10.5%, respectively, of the pregnant women were serologically positive for infection with T. cruzi. When blood samples obtained from newborns on the day of birth or, at the most, on the first few days afterwards were examined by direct microscopic observation, an incidence of congenital transmission of 3% was found. These results are consistent with those of neighboring countries. When a serologic follow-up was conducted on the newborns until six months of age, the incidence of congenital transmission reached 10%. The same incidence rate was obtained when the samples collected during the first days after birth were examined by the polymerase chain reaction (PCR). Fifty-eight infants born to seropositive mothers were followed-up, two of which were positive by direct microscopic observation at birth, and four who were PCR-positive, but microscopy-negative at birth. None of the infants were positive for IgM at birth. The infected babies were treated with benznidazole and were followed-up by serology and PCR for four years. We conclude that the PCR has a clear advantage over conventional techniques for the early detection of congenital transmission of T. cruzi infection, and for monitoring infants undergoing chemotherapy.