NEUROENDOCRINE PEPTIDES IN THE PATHOGENESIS OF COLORECTAL CARCINOMA.

Colorectal carcinoma (CRC) is the third most frequent neoplasm worldwide and the second leading cause of mortality. Neuroendocrine peptides such as glucagon, bombesin, somatostatin, cholecystokinin, and gastrin as well as growth factors such as platelet-derived growth factor, epidermal growth factor, insulin-like growth factor, and fibroblast growth factor have been postulated as being involved in carcinogenesis. The fact that these neuroendocrine peptides are involved in the development of CRC through the activation of growth factors that stimulate a series of molecular pathways that activate oncogenic signaling mechanisms is emphasized in this review. Peptides such as CCK1, serotonin, and bombesin have been found to be over-expressed in human tumor tissues. Meanwhile, the expression of peptides such as GLP2 has been seen mainly in murine models. The information contained in this review provides a better understanding of the role these peptides play in the pathogenesis of CRC for basic and clinical science studies.

One-Photon Solutions to the Multiqubit Multimode Quantum Rabi Model for Fast W-State Generation.

General solutions to the quantum Rabi model involve subspaces with an unbounded number of photons. However, for the multiqubit multimode case, we find special solutions with at most one photon for an arbitrary number of qubits and photon modes. Such solutions exist for arbitrary single qubit-photon coupling strength with constant eigenenergy, while still being qubit-photon entangled states. Taking advantage of their peculiarities and the reach of the ultrastrong coupling regime, we propose an adiabatic scheme for the fast and deterministic generation of a two-qubit Bell state and arbitrary single-photon multimode W states with nonadiabatic error less than 1%. Finally, we propose a superconducting circuit design to catch and release the W states, and shows the experimental feasibility of the multimode multiqubit quantum Rabi model.

Analog simulator of integro-differential equations with classical memristors.

An analog computer makes use of continuously changeable quantities of a system, such as its electrical, mechanical, or hydraulic properties, to solve a given problem. While these devices are usually computationally more powerful than their digital counterparts, they suffer from analog noise which does not allow for error control. We will focus on analog computers based on active electrical networks comprised of resistors, capacitors, and operational amplifiers which are capable of simulating any linear ordinary differential equation. However, the class of nonlinear dynamics they can solve is limited. In this work, by adding memristors to the electrical network, we show that the analog computer can simulate a large variety of linear and nonlinear integro-differential equations by carefully choosing the conductance and the dynamics of the memristor state variable. We study the performance of these analog computers by simulating integro-differential models related to fluid dynamics, nonlinear Volterra equations for population growth, and quantum models describing non-Markovian memory effects, among others. Finally, we perform stability tests by considering imperfect analog components, obtaining robust solutions with up to 13% relative error for relevant timescales.

Incoherent-mediator for quantum state transfer in the ultrastrong coupling regime.

We study quantum state transfer between two qubits coupled to a common quantum bus that is constituted by an ultrastrong coupled light-matter system. By tuning both qubit frequencies on resonance with a forbidden transition in the mediating system, we demonstrate a high-fidelity swap operation even though the quantum bus is thermally populated. We discuss a possible physical implementation in a realistic circuit QED scheme that leads to the multimode Dicke model. This proposal may have applications on hot quantum information processing within the context of ultrastrong coupling regime of light-matter interaction.

MALT-linfoma de cérvix: reporte de caso / MALT-lymphomas of cervix: a case report

Los linfomas MALT de cérvix son de muy rara presentación. Se reporta el caso de una paciente de 38 años con neoplasia linfoproliferativa detectada incidentalmente en los cortes de rutina, durante el estudio anátomo-patológico de espécimen de resección producto de histerectomía total, motivada por hallazgos ecográficos compatibles con miomatosis en cuerpo uterino. La etiología de esta neoplasia está asociada a procesos infecciosos o autoinmunes, se ha descrito alta radiosensibilidad y quimiosensibilidad a la biotera-pia contra anticuerpos CD20.

The MALT-lymphomas of cervix are of very rare presentation. This is the case of a 38 years old patient in which this linfoproliferative disorder was detected incidentally in the routine cuts, during the anatomo-pathological study of a resection specimen product of total hysterectomy motivated by ecographic findings that were compatible with myomatosis of the uterine corpus. The etiology of these tumors is associated with infectious or autoimmune processes, and high radiosensitivity and chemosensitivity to biotherapy against antibodies CD20 (rituximab) has been described.

p16INK4a como predictor de evolución clínica en pacientes con neoplasia intraepitelial cervical de bajo grado (NIC-I): serie de casos / p16INK4a as a predictor of clinical outcome in patients with low grade-cervical intraepithelial neoplasia

El diagnóstico morfológico de neoplasia intraepitelial cervical de bajo grado (NIC-I) no permite determinar su real riesgo de progresión a cáncer de cérvix, llevando a seguimiento estricto a un alto número de pacientes cuyas lesiones, en su mayoría, regresarán espontáneamente. La detección de p16INK4A se ha propuesto como biomarcador que permite diferenciar entre infección productiva-autolimitada por virus del papiloma humano (VPH) y transformación celular inducida por cepas oncogénicas del VPH, sin embargo, es necesario aportar evidencias de su capacidad predictiva. Se presenta una serie de 14 casos de NIC-I con detección inmunohistoquímica de p16INK4a en biopsia de cérvix (8 positivos y 6 negativos), cuya revisión retrospectiva de historial clínico de más de 12 meses de seguimiento cito-histopatológico, permite describir regresión espontánea en todos los casos p16INK4a negativo y en 3 casos p16INK4a positivo (37,5 por ciento). Los hallazgos en esta serie coinciden con lo descrito en estudios previos en los que se ha demostrado el valor predictivo negativo del marcador para descartar riesgo de progresión-persistencia y evitar seguimientos y tratamientos innecesarios. Además señalan debilidades a evaluar respecto al valor predictivo positivo de la prueba, al no discriminar algunos factores independientes de la transformación celular, determinantes en la progresión-persistencia de la NIC-I, como lo son variables genéticas y/o inmunológicas del huésped.

The morphological diagnosis of low grade-cervical intraepithelial neoplasia (CIN-1) can not determine its true risk of progression to cervical cancer, leading to strict adherence to a high number of patients whose lesions, most will return spontaneously. The detection of p16INK4a has been proposed as biomarker to differentiate between productive infection self-limiting by human papillomavirus (HPV) and cell transformation induced by oncogenic strains of HPV, however, it is necessary provide evidence of its predictive capacity. We present a series of 14 cases of CIN-1 with immunohistochemical detection of p16INK4a in cervical biopsy (8 positive and 6 negative), whose retrospective review of medical records of more than 12 months of cyto-histopathological follow, can describe spontaneous regression in all cases p16INK4a negative and in 3 cases p16INK4a positive (37.5 percent). The findings in this series of cases coincide with that described in previous studies that has been demonstrated the negative predictive value of the marker to exclude risk of progression-persistence and avoid follow-ups and unnecessary treatments. Additionally, these indicates weaknesses to evaluate about the positive predictive value of the test, by not discriminating factors independent of cellular transformation, determining the progression-persistent CIN-1, such as genetic and / or immunologic variables of the host.

[Accuracy of pedicle screw insertion in the thoracolumbar spine using image-guided navigation]. / Fiabilidad del navegador en la colocación de tornillos pediculares toracolumbares.

INTRODUCTION: Computer image guidance is one of the most significant technologic advancements in the spine surgery, because preoperative or intraoperative images can be used for multiplanar, three-dimensional intraoperative navigation. MATERIAL AND METHODS: We performed a prospective clinical study to assess the accuracy of pedicle screw insertion using an optoelectronic navigation system (SurgiGATE Spine 2.1 Medivision). The study population included 29 patients with diverse disorders of the thoraco- lumbar spine (degenerative 54%, spondylolisthesis 21%, fractures 14%, scoliosis 7% and spondylodiscitis 4%). One patient was excluded from the study because problems with the specific instruments or the computer system. Pre and post-operative axial computed tomography images were obtained for each patient and analyzed by two independent radiologists to placement accuracy. The correct location was defined accord to Heary scale in 5 grades. RESULTS: 163 image-guided thoraco-lumbar pedicle screws were placed 29 in the thoracolumbar spine and 134 in the lumbosacral spine. We achieved a completely intraosseous placement (Grade I) in 99.4% of lumbosacral spine screws and 100% of thoracolumbar spine screws. Only one misplaced screw (Grade III) in the pedicle of L III in the concavity of a scoliosis was reported. No implant related complications were noted. CONCLUSIONS: The low rate of misplaced screws in this prospective study compares favorably with previously published results. Our initial results indicate that Image-guided spinal surgery is a safe technique which improves surgical performance during posterior transpedicle stabilization.

Fiabilidad del navegador en la colocación de tornillos pediculares toracolumbares / Accuracy of pedicle screw insertion in the thoracolumbar spine using image-guided navigation

Introducción. La cirugía guiada por imagen es uno de los más importantes avances tecnológicos dentro de la cirugía del Raquis ya que permite al cirujano realizar una navegación multiplanar tridimensional en tiempo real en el interior de una vértebra. Material y métodos. Realizamos un estudio clínico prospectivo no randomizado sobre la fiabilidad en la colocación de tornillos pediculares mediante un sistema de navegación optoelectrónico (SurgiGATE Spine 2.1 Medivision). Se estudiaron veintinueve pacientes intervenidos por diferentes patologías en columna toracolumbar incluyendo: degenerativas (54%), espondilolistesis(21%), fracturas (14%), escoliosis (7%) y espondilodiscitis(4%). Un paciente fue eliminado del estudiodebido a un fallo técnico en el equipo de navegación.Se obtuvieron imágenes de TC pre y postoperatorias de cada paciente y éstas fueron evaluadas por dos neurorradiólogos independientes. La colocación correcta se definió de acuerdo a la escala de Heary en 5 grados.Resultados. Se colocaron 163 tornillos, 29 en la columnatoracolumbar y 134 en la columna lumbosacra.Hemos conseguido una colocación totalmente intraósea(Grado I) en el 99,4% de tornillos en la columnalumbosacra y en un 100% en la columna toracolumbar. Se comprobó el error de colocación (Grado III) en un pedículo de L3 en la concavidad de una escoliosis.No se observaron complicaciones relacionadas con los implantes.Conclusiones. El bajo porcentaje de tornillos mal colocados en este estudio se compara favorablemente con los resultados publicados en la literatura. Nuestros resultados indican que la cirugía guiada por imagen aplicada a la cirugía del raquis es una técnica segura para la fijación transpedicular (AU)

Introduction. Computer image guidance is one of the most significant technologic advancements in the spinesurgery, because preoperative or intraoperative images can be used for multiplanar, three-dimensional intraoperative navigation. Material and methods. We performed a prospective clinical study to assess the accuracy of pedicle screw insertion using an optoelectronic navigation system (SurgiGATE Spine 2.1 Medivision). The study population included 29 patients with diverse disorders of the thoracolumbar spine (degenerative 54%, spondylolisthesis 21%, fractures 14%, scoliosis 7% and spondylodiscitis 4%). One patient was excluded from the study because problems with the specific instruments or the computer system. Pre and post-operative axial computed tomography images were obtained for each patient and analyzed by two independent radiologists to place mentaccuracy. The correct location was defined accord to Heary scale in 5 grades. Results. 163 image-guided thoraco-lumbar pedicle screws were placed 29 in the thoracolumbar spine and 134 in the lumbosacral spine. We achieved a completely intraosseous placement (Grade I) in 99.4% of lumbosacral spine screws and 100% of thoracolumbar spinescrews. Only one misplaced screw (Grade III) in the pedicle of L III in the concavity of a scoliosis was reported. No implant related complications were noted. Conclusions. The low rate of misplaced screws in this prospective study compares favorably with previously published results. Our initial results indicate that Image-guided spinal surgery is a safe technique which improves surgical performance during posterior transpedicle stabilization (AU)

Transition to irreversibility in sheared suspensions: an analysis based on a mesoscopic entropy production.

We study the shear-induced diffusion effect and the transition to irreversibility in suspensions under oscillatory shear flow by performing an analysis of the entropy production associated with the motion of the particles. We show that the Onsager coupling between different contributions to the entropy production is responsible for the scaling of the mean square displacement on particle diameter and applied strain. We also show that the shear-induced effective diffusion coefficient depends on the volume fraction, and use lattice-Boltzmann simulations to characterize the effect through the power spectrum of particle positions for different Reynolds numbers and volume fractions. Our study gives a thermodynamic explanation of the transition to irreversibility through a pertinent analysis of the second law of thermodynamics.

Monitoring utilization and need for obstetric care in the highlands of Guatemala.

OBJECTIVE: To monitor changes in the utilization and need for obstetric care between 1995 and 1998 at three hospitals in the highlands of Guatemala. METHODS: We collected data on 5300 obstetric admissions from maternity registries and selected 10 indicators to measure intermediate outcomes. RESULTS: Utilization of services increased at some or all hospitals as measured by the number of obstetric admissions, proportion of births in facilities, and cesarean deliveries as a proportion of all births. We observed increases in the proportion of women expected to have obstetric complications who were treated at each hospital and in the proportion of women with obstetric complications who were referrals. The changes in patient profile reflect increased service utilization and accessibility among women who traditionally used the health system the least. CONCLUSIONS: Positive changes in these indicators are likely to be associated with a reduction in maternal mortality. Without a control area, we cannot be sure of a cause and effect relationship between outcomes and interventions, nevertheless, maternity registry data offer an inexpensive source of information for facilities to monitor changes.

[Cerebrovascular disease: its relationship with cardiovascular and renal pathology in 134 clinical autopsies]. / Enfermedad cerebrovascular: su relación con cardiovasculopatías y nefropatías en 134 necropsias clínicas.

OBJECTIVE: To establish the relationship between cardiopathy and chronic nephropathy, and cerebral vascular pathology in clinical necropsies performed in adult patients. MATERIAL AND METHODS: The protocols of 861 clinical autopsies done during the lapse 1990-2000 were reviewed, of these, 134 cases with diagnosis of cerebrovascular disease (CVD) were selected. Analyzed features included: neuropathological study of CVD, renal and cardiovascular pathology, and cause of death. RESULTS: CVD represented 15.5% of all autopsies done during the study period. Ischemic CVD constituted 56.7% of the cases, whereas cases of hemorrhagic CVD accounted for 43.3% of the total. Causes included arterial hypertension (33%), atherosclerosis (19%), emboli and vascular malformations (13% each, respectively), coagulopathies (8%), angeiitis (4%), tumors (1%), and unknown origin (11%). Ischemic CVD was caused by atherosclerosis in 34.2% of the cases, lacunar infarcts in 32.8%, of embolic cause in 14.4% of the cases, angeiitis in 1.3%, and of unknown origin in 17.1% of the cases. Hemorrhagic CVD presented as intraparenchymal hematoma in 50% of the cases, as sub-arachnoid hemorrhage in 28%, as disseminated petechial hemorrhages in 19%, and intraventricular in 3% of the cases. Ischemic CVD was associated with hypertensive cardiopathy in 86.5% of the cases, and with nephrosclerosis in 51.3%, whereas hemorrhagic CVD was seen associated with the same pathological entities in 86.2% and 29.3% of the cases, respectively. Cerebral herniation was the cause of death in 2.6% of the patients with ischemic CVD, and in 74.1% of the patients with hemorrhagic CVD. CONCLUSIONS: CVD was associated with a high frequency of intercurrent pathological processes, namely hypertensive cardiopathy, atherosclerosis, nephroscleroisis, and other chronic nephropathies, that eventually interact, and constitute well known predisposing and/or concomitant factors to the cerebrovascular event

Basal cell carcinoma arising in a fistula-in-ano.

Fistula-in-ano can be complicated by malignant degeneration. A case of basal cell carcinoma identified in the curettage specimen of a fistulotomy is reported. The clinicopathologic features of cases reported in the literature are reviewed.

Reconstrucción postmastectomia en cáncer de mama / Reconstruction after mastectomy in breast cancer

Se presenta la expericia del Servicio de Cirugía Plastica y de Patología Mamaria del Hospital Oncológico "Padre Machado", en pacientes con reconstrucción por cáncer de mama, desde enero 1982 hasta diciembre 1992. El método de reconstrucción en nuestro Hospital viene dado por la selección y discusión en común acuerdo entre ambos Servicios, para este trabajo se revisaron 130 casos entre los años citados, 79 pacientes pudieron ser incluidos en el análisis. La edad promedio fué de 44 años; con una paridad de 4 hijos: 31,6 por ciento (25 pacientes) eran fumadores: 33 pacientes (41,8 por ciento) tenían cirugía abdominal superior; 30 pacientes tenían receptores estrogénicos positivos. El tipo de tumor más frecuente fué 3el Adenocarcinoma Ductal Infiltrante (80 por ciento) en 60 pacientes. El estudio más frecuente fue el II 45,8 por ciento (33 pacientes) y el III 26,3 por ciento (19 pacientes); la Reconstrucción Diferida fue realizada en 41 pacientes (51,9 por ciento) e Inmediata en 38 pacientes (48,1 por ciento), el tipo de reconstrucción más frecuente fué el Colgajo de Recto Anterior en 49 pacientes (59,5 por ciento); la recidiva local fué de 5,9 por ciento (4 pacientes). Se observó metástasis en 11 casos (13,9 por ciento) de los cuales eran pacientes estadio IIIB. En la recopilación de esta experiencia se ve claramente el papel que ocupa el procedimiento reconstructivo en el tratamiento del cáncer de mama. Hoy por hoy se ha demostrado que la evolución de la enfermedad no se modifica aún en estadios avanzados, por el contrario da un apoyo psíquico y facilita la adaptación de estos pacientes a su medio. La tendencia actual es realizar Reconstrucción Inmediata en todos los casos, quedando Diferencia por criterio del equipo médico tratante ó deseo de la paciente

Prevalence of colorectal polyps in Filipinos. An autopsy study.

From May 1988 to May 1990, a prospective autopsy study was performed in patients who died at the Philippine General Hospital in Manila, Philippines. Patients younger than 10 years of age, patients with a history of large bowel resection, and patients whose deaths were related to trauma were excluded. There were 416 patients; 246 were males, and 170 were females. The mean age was 47 years (range, 11-95 years). Six of the 416 patients (1.4 percent) were found to have polyps. One patient had an inflammatory polyp, one was diagnosed with familial adenomatous polyposis, and one had an associated cecal carcinoma. Five "sporadic" adenomatous polyps were found in the remaining three patients (prevalence rate, 0.7 percent). All of the adenomatous polyps were located distal to the hepatic flexure and exhibited only mild atypia. The mean size was 6.4 mm (range, 2-20 mm). The incidence of colorectal adenomas in Filipinos is low compared with that in age-adjusted Western populations. This finding coincides with a low incidence of colorectal carcinoma. The documentation of a low risk for adenomatous polyps and colorectal cancer indicates that it would be difficult for massive screening programs to demonstrate a significant positive impact on the early detection of colorectal neoplasias in the Filipino general population.

[Leydig cell tumor associated with gynecomastia]. / Tumor de células de Leydig con ginecomastia.

We report a case of interstitial cell or Leydig cell tumor, an uncommon tumor type, that presented with evident feminizing features and acute testicular inflammatory process which warranted hospitalization. The literature is reviewed highlighting the most important aspects of this condition.

Miocardiopatía alcohólica. Informe de un caso / Alcoholic myocardiopathy. Report of a case

Se presentan los resultados clínicopatológicos de un paciente con miocardiopatía alcohólica. Se hace revisión bibliográfica de dicha afección(AU)