Efficient termination of cardiac arrhythmias using optogenetic resonant feedback pacing.

Malignant cardiac tachyarrhythmias are associated with complex spatiotemporal excitation of the heart. The termination of these life-threatening arrhythmias requires high-energy electrical shocks that have significant side effects, including tissue damage, excruciating pain, and worsening prognosis. This significant medical need has motivated the search for alternative approaches that mitigate the side effects, based on a comprehensive understanding of the nonlinear dynamics of the heart. Cardiac optogenetics enables the manipulation of cellular function using light, enhancing our understanding of nonlinear cardiac function and control. Here, we investigate the efficacy of optically resonant feedback pacing (ORFP) to terminate ventricular tachyarrhythmias using numerical simulations and experiments in transgenic Langendorff-perfused mouse hearts. We show that ORFP outperforms the termination efficacy of the optical single-pulse (OSP) approach. When using ORFP, the total energy required for arrhythmia termination, i.e., the energy summed over all pulses in the sequence, is 1 mJ. With a success rate of 50%, the energy per pulse is 40 times lower than with OSP with a pulse duration of 10 ms. We demonstrate that even at light intensities below the excitation threshold, ORFP enables the termination of arrhythmias by spatiotemporal modulation of excitability inducing spiral wave drift.

[Vulpian-Bernhardt syndrome. Its frequency and clinical and electrophysiological features in a tertiary care centre in Mexico]. / Síndrome de Vulpian-Bernhardt. Frecuencia, características clínicas y electrofisiológicas en un centro de atención de tercer nivel en México.

INTRODUCTION: Vulpian-Bernhardt syndrome (VBS) is an atypical rare clinical phenotype of amyotrophic lateral sclerosis (ALS) that causes a significant delay in diagnosis, and thus it is important to recognise its clinical and electrophysiological features. MATERIALS AND METHODS: Retrospective cross-sectional study. We reviewed the clinical records of patients diagnosed with ALS in the period from January to December 2019. Those meeting criteria for VBS were included so as to describe their frequency as well as their clinical and electrophysiological features. RESULTS: Twenty patients (15.8%) met criteria for VBS; 55% were female; age at onset of symptoms was 46.6 ± 12.9 years; 40% were smokers; median delay in diagnosis was 24 (12-96) months; median time to involvement of the second body segment was 24 (12-132) months, which was lumbosacral in 65%; mean Revised Amyotrophic Lateral Sclerosis Functional Rating Scale score was 27 ± 7 points; 45% met the El Escorial criteria for ALS defined at diagnosis and 58.8% met the Awaji criteria. There were 19 nerve conduction studies and 17 electromyograms, and an abductor digiti minimi-abductor pollicis brevis (ADM/APB) ratio < 0.6 was found in 63% (split hand). CONCLUSIONS: There is a significant delay in the diagnosis of motor neuron diseases in general and more particularly in VBS. Calculating the ADM/APB ratio and applying the Awaji criteria in the electrophysiology study can be a valuable aid to increase diagnostic certainty in this clinical entity.

TITLE: Síndrome de Vulpian-Bernhardt. Frecuencia, características clínicas y electrofisiológicas en un centro de atención de tercer nivel en México.Introducción. El síndrome de Vulpian-Bernhardt (SVB) es un fenotipo clínico atípico e infrecuente de la esclerosis lateral amiotrófica (ELA) que condiciona un importante retraso diagnóstico, por lo que reconocer sus características clínicas y electrofisiológicas tiene relevancia. Materiales y métodos. Estudio retrospectivo y transversal. Se revisaron los expedientes clínicos de pacientes con diagnóstico de ELA en el período de enero de 2017 a diciembre de 2019. Se incluyeron los que cumplían criterios para SVB para describir su frecuencia, características clínicas y electrofisiológicas. Resultados. Veinte pacientes (15,8%) cumplieron los criterios para el SVB; el 55% eran mujeres; la edad de inicio de los síntomas era de 46,6 ± 12,9 años; presentaba tabaquismo el 40%; la mediana de retraso del diagnóstico fue de 24 (12-96) meses; la mediana en afectarse un segundo segmento corporal fue de 24 (12-132) meses, que fue el lumbosacro en el 65%; el promedio en la escala Revised Amyotrophic Lateral Sclerosis Functional Rating Scale fue de 27 ± 7 puntos; el 45% cumplía los criterios de El Escorial para ELA definida en el momento del diagnóstico y el 58,8%, los de Awaji. Se contó con 19 estudios de neuroconducción y 17 electromiogramas, y se encontró una razón abductor digiti minimi-abductor pollicis brevis (APB/ADM) menos de 0,6 en el 63% (mano dividida). Conclusiones. Existe un retraso importante en el diagnóstico de enfermedades de la motoneurona en general y de SVB en particular. Calcular la razón APB/ADM y aplicar los criterios de Awaji en el estudio de electrofisiología puede ser de gran ayuda para aumentar la certeza diagnóstica en esta entidad clínica.

Molecular cloning and expression of a GABA receptor subunit from the crayfish Procambarus clarkii.

Molecular cloning has introduced an unexpected, large diversity of neurotransmitter hetero- oligomeric receptors. Extensive research on the molecular structure of the γ-aminobutyric acid receptor (GABAR) has been of great significance for understanding how the nervous system works in both vertebrates and invertebrates. However, only two examples of functional homo-oligomeric GABA-activated Cl(-) channels have been reported. In the vertebrate retina, the GABAρ1 subunit of various species forms homo-oligomeric receptors; in invertebrates, a cDNA encoding a functional GABA-activated Cl(-) channel has been isolated from a Drosophila melanogaster head cDNA library. When expressed in Xenopus laevis oocytes, these subunits function efficiently as a homo-oligomeric complex. To investigate the structure-function of GABA channels from the crayfish Procambarus clarkii, we cloned a subunit and expressed it in human embryonic kidney cells. Electrophysiological recordings show that this subunit forms a homo-oligomeric ionotropic GABAR that gates a bicuculline-insensitive Cl(-) current. The order of potency of the agonists was GABA > trans-4-amino-crotonic acid = cis-4-aminocrotonic acid > muscimol. These data support the notion that X-organ sinus gland neurons express at least two GABA subunits responsible for the formation of hetero-oligomeric and homo-oligomeric receptors. In addition, by in situ hybridization studies we demonstrate that most X-organ neurons from crayfish eyestalk express the isolated pcGABAA ß subunit. This study increases the knowledge of the genetics of the crayfish, furthers the understanding of this important neurotransmitter receptor family, and provides insight into the evolution of these genes among vertebrates and invertebrates.

Association of Metastasis with Clinicopathological Data in Mexican Patients with Osteosarcoma, Giant Cell Tumor of Bone and Chondrosarcoma.

BACKGROUND: Bone tumors are neoplasias with a high overall mortality; one of the main factors that reduce survival is their high capacity to develop metastases. It has been reported that finding lung metastases at diagnosis of osteosarcoma (OS), chondrosarcoma (CS) and giant cell tumor of bone (GCTb) is quite common. In this study, we inquire the relationship of metastases caused by these tumors with different clinical and pathological aspects, in order to guide medical personnel in the diagnosis and opportune treatment of metastases or micro metastases. MATERIALS AND METHODS: We collected data of 384 patients with clinical, radiological and histopathological diagnosis of OS, GCTb and CS that attended the National Rehabilitation Institute (INR) during 2006 to 2014. Chi-square and Fisher's exact tests were performed for data analysis. RESULTS: In the three tumor types, the presence of metastases at diagnosis was variable (p=0.0001). Frequency of metastases was 36.7%, 31.7% and 13.2% for OS, CS and GCTb respectively. The average age had no significant difference (p>0.05) in relation to metastases, even so, patients with OS and GCTb and metastases, were older while patients with CS and metastases were younger, in comparison to patients without metastases. Males had a higher frequency of metastases (68.2%, p = 0.09) in contrast to CS and GCTb, in which the metastases was more frequent in women with 51.9% (p = 0.44) and 57.9% (p = 0.56) respectively. Broadly, metastasis was associated with primary tumors located in the femur (44.4%), followed by the tibia (15.6%); metastases was more frequent when primary tumor of GCTb and OS were in the same bones, but were located in the hip (26.3%) for CS. CONCLUSIONS: The frequency of metastases in OS, GCTb and CS is high in our population and is determined by different clinicopathological variables related to the kind of tumor. Further studies are needed in order to evaluate metastases subsequent to diagnosis and associations with survival and clinicopathological factors , as well as to determine the sensitivity and specificity of current methods of detection.

Dynamic point shifting with null screens using three LCDs as targets for corneal topography.

In this paper, the use of three liquid crystal displays (LCDs) as targets for an experimental corneal topographer is proposed. The main advantage is that the geometrical pattern in the target can be modified without moving any mechanical part to apply the dynamic point shifting (DyPoS) method. Some results on the capabilities of the LCDs, obtained with photo frames, for measuring a 6.37 mm radius of curvature calibration sphere, and applying the DyPoS method, are presented. It is shown that the error in measuring the radius of curvature with DyPoS is reduced to 3% of the real value and the RMS in elevation or sagitta differences is around 15 µm, 30% or 66% of the values obtained without DyPoS, respectively.

Electron beam inactivation of Tulane virus on fresh produce, and mechanism of inactivation of human norovirus surrogates by electron beam irradiation.

Ionizing radiation, whether by electron beams or gamma rays, is a non-thermal processing technique used to improve the microbial safety and shelf-life of many different food products. This technology is highly effective against bacterial pathogens, but data on its effect against foodborne viruses is limited. A mechanism of viral inactivation has been proposed with gamma irradiation, but no published study discloses a mechanism for electron beam (e-beam). This study had three distinct goals: 1) evaluate the sensitivity of a human norovirus surrogate, Tulane virus (TV), to e-beam irradiation in foods, 2) compare the difference in sensitivity of TV and murine norovirus (MNV-1) to e-beam irradiation, and 3) determine the mechanism of inactivation of these two viruses by e-beam irradiation. TV was reduced from 7 log10 units to undetectable levels at target doses of 16 kGy or higher in two food matrices (strawberries and lettuce). MNV-1 was more resistant to e-beam treatment than TV. At target doses of 4 kGy, e-beam provided a 1.6 and 1.2 log reduction of MNV-1 in phosphate buffered saline (PBS) and Dulbecco's Modified Eagle Medium (DMEM), compared to a 1.5 and 1.8 log reduction of TV in PBS and Opti-MEM, respectively. Transmission electron microscopy revealed that increased e-beam doses negatively affected the structure of both viruses. Analysis of viral proteins by SDS-PAGE found that irradiation also degraded viral proteins. Using RT-PCR, irradiation was shown to degrade viral genomic RNA. This suggests that the mechanism of inactivation of e-beam was likely the same as gamma irradiation as the damage to viral constituents led to inactivation.

Use of air stacking and abdominal compression for cough assistance in people with complete tetraplegia.

STUDY DESIGN: Cross-sectional. OBJECTIVE: To assess cough using air stacking (AS) to assist inspiratory volume with abdominal compression (AC) during expiration in patients with American Spinal Injury Association Impairment Scale (AIS) A. SETTING: Large tertiary hospital in Chile. METHODS: Peak cough flow (PCF) was measured during four different interventions: spontaneous maximal expiratory effort (MEE); MEE while receiving AC (MEE-AC); MEE after AS with a manual resuscitation bag (AS-MEE); and MEE with AS and AC (AS-MEE-AC). RESULTS: Fifteen in-patients with complete tetraplegia (C4-C6) were included. Median age was 33 years (16-56). PCF during the different interventions was PCF for MEE was 183±90 l min(-1); PCF for MEE-AC was 273±119 l min(-1); PCF for AS-MEE was 278±106 l min(-1) and PCF for AS-MEE-AC was 368±129 l min(-1). We observed significant differences in PCF while applying MEE-AC and AS-MEE compared with MEE (P=0.0001). However, the difference in PCF value was greater using the AS-MEE-AC technique (P=0.00001). CONCLUSION: Patients with spinal cord injury (SCI) presented an ineffective cough that constitutes a risk factor for developing respiratory complications. The application of combined techniques (AS-MEE-AC) can reach near normal PCF values. This is a low-cost, simple and easily applied intervention that could be introduced to all patients with tetraplegia.

TnaA, an SP-RING protein, interacts with Osa, a subunit of the chromatin remodeling complex BRAHMA and with the SUMOylation pathway in Drosophila melanogaster.

Tonalli A (TnaA) is a Drosophila melanogaster protein with an XSPRING domain. The XSPRING domain harbors an SP-RING zinc-finger, which is characteristic of proteins with SUMO E3 ligase activity. TnaA is required for homeotic gene expression and is presumably involved in the SUMOylation pathway. Here we analyzed some aspects of the TnaA location in embryo and larval stages and its genetic and biochemical interaction with SUMOylation pathway proteins. We describe that there are at least two TnaA proteins (TnaA130 and TnaA123) differentially expressed throughout development. We show that TnaA is chromatin-associated at discrete sites on polytene salivary gland chromosomes of third instar larvae and that tna mutant individuals do not survive to adulthood, with most dying as third instar larvae or pupae. The tna mutants that ultimately die as third instar larvae have an extended life span of at least 4 to 15 days as other SUMOylation pathway mutants. We show that TnaA physically interacts with the SUMO E2 conjugating enzyme Ubc9, and with the BRM complex subunit Osa. Furthermore, we show that tna and osa interact genetically with SUMOylation pathway components and individuals carrying mutations for these genes show a phenotype that can be the consequence of misexpression of developmental-related genes.

A functional study of nucleocytoplasmic transport signals of the EhNCABP166 protein from Entamoeba histolytica.

EhNCABP166 is an Entamoeba histolytica actin-binding protein that localizes to the nucleus and cytoplasm. Bioinformatic analysis of the EhNCABP166 amino acid sequence shows the presence of 3 bipartite nuclear localization signals (NLS) and a nuclear export signal (NES). The present study aimed to investigate the functionality of these signals in 3 ways. First, we fused each potential NLS to a cytoplasmic domain of ehFLN to determine whether the localization of this domain could be altered by the presence of the NLSs. Furthermore, the localization of each domain of EhNCABP166 was determined. Similarly, we generated mutations in the first block of bipartite signals from the domains that contained these signals. Additionally, we added an NES to 2 constructs that were then evaluated. We confirmed the intranuclear localization of EhNCABP166 using transmission electron microscopy. Fusion of each NLS resulted in shuttling of the cytoplasmic domain to the nucleus. With the exception of 2 domains, all of the evaluated domains localized within the nucleus. A mutation in the first block of bipartite signals affected the localization of the domains containing an NLS. The addition of an NES shifted the localization of these domains to the cytoplasm. The results presented here establish EhNCABP166 as a protein containing functional nuclear localization signals and a nuclear export signal.

Food-restricted and dehydrated-induced anorexic rats present differential TRH expression in anterior and caudal PVN. Role of type 2 deiodinase and pyroglutamyl aminopeptidase II.

TRH synthesized in hypothalamic paraventricular nucleus (PVN) regulates thyroid axis function and is also implicated in anorexigenic effects. Under energy deficit, animals present decreased PVN TRH expression and release, low TSH levels, and increased appetite. Dehydration-induced anorexia (DIA) model allows insight into underlying mechanisms of feeding regulation. Animals drinking a 2.5% NaCl solution for 7 d present body weight reduction; despite their negative energy balance, they avoid food and have increased PVN TRH expression and TSH serum levels. These findings support an inhibiting role of PVN TRH in feeding control. We compared TRH expression by in situ hybridization in PVN subdivisions of 7-d dehydrated male rats to those of a pair-fed group (forced food-restricted) with similar metabolic changes than DIA, but motivated to eat, and to controls. We measured peripheral deiodinase activities, and expression and activity of medial basal hypothalamic type 2 deiodinase and pyroglutamyl-aminopeptidase II, to understand their regulating role in PVN TRH changes between food restriction and anorexia. TRH mRNA levels increased in anterior (aPVN) and medial-caudal subdivisions in DIA rats, whereas it decreased in medial PVN in both experimental groups. We confirmed the nonhypophysiotropic nature of aPVN TRHergic cells by injecting ip fluorogold tracer. Findings support a subspecialization of TRHergic hypophysiotrophic cells that responded differently between anorexic and food-restricted animals; also, that aPVN TRH participates in food intake regulation. Increased type 2 deiodinase activity seemed responsible for low medial PVN TRH synthesis, whereas increased medial basal hypothalamic pyroglutamyl-aminopeptidase II activity in DIA rats might counteract their high TRH release.

The gamma ray response of alanine film dosimeters at low temperatures.

The response of alanine film EPR dosimeters was studied for low temperature gamma irradiation conditions (77-293 K) in the dose interval from 6.3 to 80 kGy. It was found that the response of the dosimeter decreases with decreased irradiation temperature and saturates at lower doses for lower irradiation temperatures. The analysis of the EPR signal suggests that the radical species formed at low temperature are the same as those used for dosimetry at room temperature, but with different concentrations. Their concentrations evolve as the temperature of the sample increases until the usual EPR signal used at room temperature is obtained.

Electron beam irradiation dose dependently damages the bacillus spore coat and spore membrane.

Effective control of spore-forming bacilli begs suitable physical or chemical methods. While many spore inactivation techniques have been proven effective, electron beam (EB) irradiation has been frequently chosen to eradicate Bacillus spores. Despite its widespread use, there are limited data evaluating the effects of EB irradiation on Bacillus spores. To study this, B. atrophaeus spores were purified, suspended in sterile, distilled water, and irradiated with EB (up to 20 kGy). Irradiated spores were found (1) to contain structural damage as observed by electron microscopy, (2) to have spilled cytoplasmic contents as measured by spectroscopy, (3) to have reduced membrane integrity as determined by fluorescence cytometry, and (4) to have fragmented genomic DNA as measured by gel electrophoresis, all in a dose-dependent manner. Additionally, cytometry data reveal decreased spore size, increased surface alterations, and increased uptake of propidium iodide, with increasing EB dose, suggesting spore coat alterations with membrane damage, prior to loss of spore viability. The present study suggests that EB irradiation of spores in water results in substantial structural damage of the spore coat and inner membrane, and that, along with DNA fragmentation, results in dose-dependent spore inactivation.

Electron-beam inactivation of a norovirus surrogate in fresh produce and model systems.

Norovirus remains the leading cause of foodborne illness, but there is no effective intervention to eliminate viral contaminants in fresh produce. Murine norovirus 1 (MNV-1) was inoculated in either 100 ml of liquid or 100 g of food. The inactivation of MNV-1 by electron-beam (e-beam), or high-energy electrons, at varying doses was measured in model systems (phosphate-buffered saline [PBS], Dulbecco's modified Eagle's medium [DMEM]) or from fresh foods (shredded cabbage, diced strawberries). E-beam was applied at a current of 1.5 mA, with doses of 0, 2, 4, 6, 8, 10, and 12 kGy. The surviving viral titer was determined by plaque assays in RAW 264.7 cells. In PBS and DMEM, e-beam at 0 and 2 kGy provided less than a 1-log reduction of virus. At doses of 4, 6, 8, 10, and 12 kGy, viral inactivation in PBS ranged from 2.37 to 6.40 log, while in DMEM inactivation ranged from 1.40 to 3.59 log. Irradiation of inoculated cabbage showed up to a 1-log reduction at 4 kGy, and less than a 3-log reduction at 12 kGy. On strawberries, less than a 1-log reduction occurred at doses up to 6 kGy, with a maximum reduction of 2.21 log at 12 kGy. These results suggest that a food matrix might provide increased survival for viruses. In foods, noroviruses are difficult to inactivate because of the protective effect of the food matrix, their small sizes, and their highly stable viral capsid.

Descripción de los conocimientos, actitudes, susceptibilidad y autoeficacia frente al VIH/SIDA en un grupo de adolescentes colombianos

La presente investigación tiene como objetivo describir y comparar los conocimientos correctos,las ideas erróneas, las actitudes, la susceptibilidad y autoeficacia frente al VIH/SIDA en un grupode adolescentes colombianos. La muestra está conformada por 222 adolescentes de ambos sexos,entre los 10 y 18 años (media 14.10 y desviación típica 1.925) que pertenecen a una instituciónpública de la ciudad de Cali. Es una investigación descriptivo-correlacional (Montero y León, 2005).La información se recogió mediante la aplicación de la Adaptación Colombiana de la escala VIH-65 (Bermúdez, Buela-Casal y Uribe (2005), que mide conocimientos, actitudes, susceptibilidad yautoeficacia frente al VIH/SIDA. Los resultados evidencian que la escala que obtuvo mayor puntuaciónes la de conocimientos erróneos, lo que indica que aún persisten conceptos errados y mitos frente alVIH/SIDA. Igualmente, se encontró que existen diferencias significativas en función de la edad, laescolaridad y el sexo...

The objective of this research is to describe and compare correct knowledge, incorrect ideas, attitudes,susceptibility and self-efficacy in cases of HIV/AIDS in a group of Colombian adolescents. Thesample consists of 222 adolescents of both sexes between the ages of 10 and 18. (Average 14.10 anda typical deviation of 1.925), who belong to a public institution in the city of Cali. This is descriptivecorrelationalresearch (Montero and León, 2005). The information was gathered by the applicationof the Colombian adaptation of the HIV-65 scale (Bermúdez, Buela-Casal and Uribe (2005), whichmeasures knowledge, attitudes, susceptibility, and self-efficacy in cases of HIV/AIDS. The results show that the scale obtaining the highest score is that of incorrect knowledge, which suggests thatthere are still erroneous and mythical concepts about HIV/AIDS. It was also found that there aredifferent meanings depending on age, academic level and sex...

A presente investigação tem como objetivo descrever e comparar os conhecimentos corretos, asidéias errôneas, as atitudes, a suscetibilidade e auto-eficácia contra o HIV/AIDS em um grupo deadolescentes colombianos. A mostra está conformada por 222 adolescentes de ambos sexos, entre os10 e 18 anos (meia 14.10 e desvio típica 1.925) que pertencem a uma instituição pública da cidade deCali. É uma investigação descritivo-correlacional (Montero y León, 2005). A informação se recolheumediante a aplicação da Adaptação Colombiana da escala HIV-65 (Bermúdez, Buela-Casal y Uribe(2005), que mede conhecimentos, atitudes, suscetibilidade e auto-eficácia contra o HIV/AIDS. Osresultados evidenciam que a escala que obteve maior pontuação é a de conhecimentos errôneos, o queindica que ainda persistem conceitos errados e mitos contra o HIV/AIDS. Igualmente se encontrouque existem diferenças significativas em função da idade, a escolaridade e o sexo...

17ß-Oestradiol indirectly inhibits thyrotrophin-releasing hormone expression in the hypothalamic paraventricular nucleus of female rats and blunts thyroid axis response to cold exposure.

Energy expenditure and thermogenesis are regultated by thyroid and sex hormones. Several parameters of hypothalamic-pituitary-thyroid (HPT) axis function are modulated by 17ß-oestradiol (E(2)) but its effects on thyrotrophin-releasing hormone (TRH) mRNA levels remain unknown. We evaluated, by in situ hybridisation and Northern bloting, TRH expression in the paraventricular nucleus of the hypothalamus (PVN) of cycling rats, 2 weeks-ovariectomised (OVX) and OVX animals injected s.c. during 1-4 days with E(2) (5, 50, 100 or 200 µg / kg) (OVX-E). Serum levels of E(2), thyroid-stimulating hormone (TSH), prolactin, corticosterone and triiodothyronine (T(3)) were quantified by radioimmunoassay. Increased serum E(2) levels were observed after 4 days injection of 50 µg / kg E(2) (to 68.5 ± 4.8 pg / ml) in OVX rats. PVN-TRH mRNA levels were slightly higher in OVX than in virgin females at dioestrous 1 or pro-oestrous, decreasing proportionally to increased serum E(2) levels. E(2) injections augmented serum T(3), prolactin, and corticosterone levels. Serum TSH levels augmented with 4 days 50 µg / kg E(2), but not with the higher doses that enhanced serum T(3) levels. Exposure to cold for 1 h resulted in marked HPT axis activation in OVX rats, increasing the levels of TRH mRNA along the rostro-caudal PVN areas, as well as serum TSH, T(3), corticosterone and prolactin levels. By contrast, no significant changes in any of these parameters were observed in cold-exposed OVX-E (50 µg / kg E(2)) rats. Very few PVN-TRHergic neurones expressed the oestrogen receptor type-α, suggesting that the effects of E(2) on PVN-TRH expression are indirect, most probably as a result of its multiple modulatory effects on circulating hormones and their receptor sensitivity. The blunted response of OVX-E rats to cold coincides with the effects of E(2) on the autonomic nervous system and increased cold tolerance.

Hiperparatiroidismo primario y embarazo: reporte de un caso / Primary hyperparathyroidism and pregnancy: a case report

El hiperparatiroidismo primario (HPTP) se caracteriza por una hipersecreción autónoma de paratohormona (PTH), lo que provoca hipercalcemia e hipercalciuria, con afectación ósea, renal y de otras partes del organismo, en grado variable. El HPTP tiene una prevalencia de 1 en 1000 en la población general y se presenta con mayor frecuencia en mujeres que en hombres. Es infrecuente su presentación en el embarazo, y sus complicaciones derivadas de la hipercalcemia pueden afectar tanto a la madre como al feto. Presentamos el caso de una paciente de 37 años, cursando un embarazo de 10 semanas, que ingresó al servicio con los diagnósticos de nefrocalcinosis y pielonefritis aguda, a la que se diagnosticó un hiperparatiroidismo primario, cuya etiología fue un adenoma paratiroideo único.

Primary hyperparathyroidism (HPTP) is a disorder characterized by elevated levels of parathyroid hormone (PTH), which leads to hypercalcemia and hypercalciuria, with variable osseous, renal and other systems affectation. HPTP has a prevalence of 1:1000 in general population and is more frequent in women than men. It is very rare during pregnancy, and its complications are produced by hypercalcemia and they can affect the mother and the fetus. We present the case of a 37 year old woman, with a 10+2 weeks pregnancy that was admitted in our Hospital with nephrocalcinosis and urinary tract infection, whom was diagnosed primary hyperparathyroidism, whose etiology was a single parathyroid adenoma.

Point shifting in the optical testing of fast aspheric concave surfaces by a cylindrical screen.

A method for increasing the precision and sensitivity of the quantitative evaluation of fast aspheric surfaces through the null screen method is presented. This consists of applying small displacements to the cylindrical null screen along the optical axis. These movements allow a scan of the image spots over zones that with the analysis of a single image are more difficult to evaluate. The precision of the test is increased due to a greater density of sampling reducing the numerical errors during the integration. Results of the evaluation of an elliptical concave mirror on axis show that the numerical integration errors can be reduced from 20% for short paths to 80% for larger integration paths.

Testing fast aspheric concave surfaces with a cylindrical null screen.

A noncontact test procedure to obtain the shape of fast concave surfaces is described. A cylindrical null screen with a curved grid drawn on it in such a way that its image, which is formed by reflection on a perfect concave surface, yields a perfect square grid is proposed. The cylindrical null screen design and the surface evaluation algorithm are presented. Experimental results for the testing of an elliptical mirror of 164 mm in diameter (f/0.232) are shown.

Síndrome de Eisenmenger y embarazo / Eisenmenger syndrome and pregnancy

ANTECEDENTES: El embarazo está contraindicado en toda paciente con hipertensión pulmonar, y particularmente en aquellas con síndrome de Eisenmenger. OBJETIVO: Describir 3 casos de embarazadas con síndrome de Eisenmenger, tratadas con sildenafil. RESULTADOS: El desarrollo del embarazo se complicó en las tres pacientes con parto prematuro, a las 30, 28 y 35 semanas, respectivamente. En 2 pacientes el parto se resolvió mediante operación cesárea. No hubo mortalidad materna ni perinatal. CONCLUSIÓN: El síndrome de Eisenmenger es de alto riesgo de morbimortalidad materno-perinatal y el manejo multidisciplinario optimiza los resultados. Se describe el uso de sildenafil.

BACKGROUND: Pregnancy in contraindicated in patient with pulmonary hypertension, especially in dose with Eisenmenger syndrome. OBJECTIVE: To present 3 cases of pregnancy in patients with Eisenmenger syndrome treated with sildenafil. RESULTS: The pregnancy becomes complicated in the 3 cases, with premature delivery at 30, 28 and 35 weeks respectively. Cesarean delivery was performed in two cases. There was no maternal or perinatal mortality. CONCLUSION: The Eisenmenger syndrome is a high risk condition of maternal-perinatal morbimortality and the multidisciplinary handling optimizes the results. The sildenafil use is described.

Testing a fast off-axis parabolic mirror by using tilted null screens.

We propose the design of tilted null screens for testing off-axis segments of conic surfaces. The tilt allows us to control the size of the screen and the sensitivity of the test. For positive tilt angles the sensitivity is increased while the size of the screen is reduced in the sagittal caustic region and vice versa in the tangential caustic region. Further analysis and preliminary experimental results are presented for a fast off-axis concave parabolic mirror with an elliptical aperture. An offset distance of X(C) = 25.4 mm yields radius of curvature at the vertex R = 20.4 mm; major axis of the mirror D(M) = 49.4 mm; and minor axis D(m) = 29.5 mm.