Carlos Uribe

Foreign direct investment received in the oil sector in Colombia is a dependent variable, based on percentages with respect to GDP of exports of goods and services, and gross capital formation as independent. This work highlights the oil sector within the Colombian economy and the important role that foreign investors have had in this sector. The link between this variable and another macroeconomic variable was identify within the parameters marked within the model of multiple linear regression. This research is quantitative, of an explanatory type and is framed within the paradigm of structuralism. In this research work, the SPSS statistical program for modeling is implemented and the econometric model of direct foreign investment of the Colombian oil sector between 1996 and 2016 is sought.

RESUMEN: Se analizaron diferencias y comportamientos de los países pertenecientes a Mercosur y Alianza-Pacifico durante el periodo 20122017 en materia de competitividad y posicionamiento global, utilizando como variables los doce pilares del Foro Económico Mundial. La metodología cuantitativaanalítica, utiliza el análisis discriminante para clasificar eficazmente la pertenencia de los países entre los bloques. De 12 variables, 3 entorno macroeconómico, salud-educación primaria, tamaño del mercadoson discriminantes en materia de competitividad país. El modelo permitió alta predictibilidad con 100% clasificado correctamente. Palabras clave: Análisis discriminante, Competitividad, Economía internacional ABSTRACT: Differences and behaviors of the countries belonging to Mercosur and Pacific Alliance during the 2012-2017 period were analyzed in terms of competitiveness and global positioning, using as variables the twelve pillars of the World Economic Forum. The quantitative-analytical me...

Background Patients with metastatic, castration-resistant prostate cancer (mCRPC) present with an increased tumor burden in the skeleton. For these patients, Lutetium-177 (Lu-177) radioligand therapy targeting the prostate-specific membrane antigen (PSMA) has gained increasing interest with promising outcome data. Patient-individualized dosimetry enables improvement of therapy success with the aim of minimizing absorbed dose to organs at risk while maximizing absorbed dose to tumors. Different dosimetric approaches with varying complexity and accuracy exist for this purpose. The Medical Internal Radiation Dose (MIRD) formalism applied to tumors assumes a homogeneous activity distribution in a sphere with unit density for derivation of tumor S values (TSV). Voxel S value (VSV) approaches can account for heterogeneous activities but are simulated for a specific tissue. Full patient-individual Monte Carlo (MC) absorbed dose simulation addresses both, heterogeneous activity and density ...

Camera calibration, which translates reconstructed count map into absolute activity map, is a prerequisite procedure for quantitative SPECT imaging. Both planar and tomographic scans using different phantom geometries have been proposed for the determination of the camera calibration factor (CF). However, there is no consensus on which approach is the best. The aim of this study is to evaluate all these calibration methods, compare their performance, and propose a practical and accurate calibration method for SPECT quantitation of therapeutic radioisotopes. Twenty-one phantom experiments (Siemens Symbia SPECT/CT) and 12 Monte Carlo simulations (GATE v6.1) using three therapy isotopes (I, Lu, and Re) have been performed. The following phantom geometries were used: (1) planar scans of point source in air (PS), (2) tomographic scans of insert(s) filled with activity placed in non-radioactive water (HS + CB), (3) tomographic scans of hot insert(s) in radioactive water (HS + WB), and (4)...

The aim of the study is to assess accuracy of activity quantification of (177)Lu studies performed according to recommendations provided by the committee on Medical Internal Radiation Dose (MIRD) pamphlets 23 and 26. The performances of two scatter correction and three segmentation methods were compared. Additionally, the accuracy of tomographic and planar methods for determination of the camera normalization factor (CNF) was evaluated. Eight phantoms containing inserts of different sizes and shapes placed in air, water, and radioactive background were scanned using a Siemens SymbiaT SPECT/CT camera. Planar and tomographic scans with (177)Lu sources were used to measure CNF. Images were reconstructed with our SPEQToR software using resolution recovery, attenuation, and two scatter correction methods (analytical photon distribution interpolated (APDI) and triple energy window (TEW)). Segmentation was performed using a fixed threshold method for both air and cold water scans. For hot ...

We previously identified in two families with early onset Parkinson's Disease (PD) from the isolated population of Antioquia (Colombia), a parkin Cys212Tyr substitution caused by a G736A mutation. This mutation was subsequently observed in a Spanish family, suggesting that it could have been taken to Antioquia by Spanish immigrants. Here we screened for the G736A mutation in additional Antioquian early onset PD cases and used haplotype analysis to investigate the relationship between Spanish and Antioquian G736A chromosomes. We confirmed the occurrence of an extensive founder effect in Antioquia. Thirteen individuals (10 homozygotes) from seven nuclear families were identified with the G736A mutation. Genealogical investigations demonstrated the existence of shared ancestors between six of these families four to five generations ago and no evidence of Spanish ancestry during this period. A second parkin mutation (a duplication of exon 3), was detected in the three G736A heterozygote carriers. Haplotype data exclude a recent common ancestry between the Spanish and Antioquian patients studied here and is consistent with the introduction of the G736A mutation in Antioquia during early colonial times (about 16 generations ago).

A 46-year-old female presented with a 1-week history of mental change, confusion and headaches. Investigations revealed evidence of sterile meningitis. CAT scanning of the brain demonstrated marked contrast enhancement around the ependyma, and later examinations showed extension of the process deep into the white matter, Cerebral biopsies were non-diagnostic and, despite ventricular drainage and treatment with antibiotics and high dose steriods, the patent died. At postmortem there was extensive tumour tissue distributed in a butterfly shape around the ventricles, and microscopy revealed typical apperances of primary CNS lymphoma. On the basis of the experience of this case and a review of recent literature, it is suggested that the CAT scan appearances of this tumour are quite typical, and that cranial irradiation may be justified in the absence of specific histological diagnosis.

La encefalitis letárgica de von Economo es un trastorno neuropsiquiátrico de posible origen autoinmunitario, en el cual se afectan los ganglios basales. Esta reacción puede ocurrir luego de una infección aguda por diversos agentes virales o bacterianos. Dado que aparece cuando ya se ha resuelto el cuadro agudo, se ha propuesto el mecanismo del mimetismo molecular para explicar la lesión autoinmunitaria. Se han reportado diversos casos a lo largo del tiempo, pero fue con la pandemia de influenza de 1918, conocida como la gripe española, que la encefalitis letárgica alcanzó niveles de epidemia, con casos reportados hasta 1923 en diversos países.La pandemia de la gripe española se extendió a Colombia durante los últimos meses de 1918 y afectó varias ciudades, principalmente Bogotá, donde se reportó el mayor número de enfermos y muertos. Con este trabajo se busca rememorar, cien años después, el ingreso de la gripe española a nuestro país y sus principales complicaciones, entre las que ...

The purpose of this study was to determine the diagnostic value of the palmomental reflex in order to identify frontal lesions in neurological outpatients. Two hundred twenty-six neurological patients with suspected intracranial lesion with an indication for magnetic resonance imaging (MRI) were included. All patients underwent the same MRI protocol. The reflex was elicited by trained and standardized nurses, and was evaluated by two neurologists. The evaluation was blind and independent. The test's accuracy was calculated. The Kappa coefficient was used to calculate the interobserver and intra-observer reliability. The interobserver reliability between neurologists was 0.53 with 93% of agreement (p<0.001). The diagnostic accuracy measures were as follow: sensitivity of 19%, specificity of 93%, positive predictive value of 30%, negative predictive value of 88%, positive likelihood ratio of 2.7 and negative likelihood ratio of 0.87. The area under the curve was 0.56. The palmomental reflex is associated with frontal structural lesions but the sensitivity is low, indicating a high percentage of frontal lesions with a negative reflex. When the test is used on its own, it is insufficient to detect frontal damage.

Thrombosis of the cerebral venous sinuses (TCVS) is an infrequent entity that still represents a challenge in health care. A descriptive study involving the evaluation of the medical records of patients that met the following criteria: over 18 years of age with a diagnosis of TCVS confirmed by CAT scan or cranial MRI, the absence of a history of intracranial surgery in the previous six months and absence of a history of intracranial infection. A total of 15 patients (14 females and one male) were found with an average age of 28.6 years. The time required for the development of the most frequent symptoms was 1 10 days (60%). The usual presentation was a syndrome of intracranial hypertension with focalisation and encephalopathy. Risk factors were identified in 13 patients (87%). TCVS was diagnosed by cranial MRI in the case of 14 patients (93%), by CAT scanning in one (7%) and this was also used to orient diagnosis in 12 cases (80%). The most frequently affected sinuses were the superior longitudinal and transverse, in 10 cases each (66%), and venous infarctions were also detected in 10 patients (66%). In the patients in whom we were able to evaluate clotting disorders, it was found that the only individual who displayed activated protein C resistance was positive, three out of four patients had a protein C deficiency and four out of six had an antithrombin III deficiency. TCVS presents as an intracranial hypertension syndrome and it is possible to find risk factors in as many as 85% of the cases.

Different patterns of headache have been reported in idiopathic intracranial hypertension. We conducted a retrospective study to evaluate patients in a Columbian hospital who satisfied Friedman and Jacobson criteria for idiopathic intracranial hypertension. Two groups of patients, with throbbing headaches (TH) and heaviness/oppressive headaches (HOH), were correlated with International Headache Society classification criteria. We found 16 patients, 14 of whom were females (87.5%), with a mean age of 27 years. Patients had a history of two months or more (43.7%), 1-2 months (25%) and 2 weeks (18.7%). Six patients were found to be suffering from TH and nine had HOH. In the TH group, headaches were hemicranial (50%), frontal (33.3%), moderate (33.3%), severe (66.6%), got worse with activity (100%), with sickness/vomiting (83.3%), and photophobia (33.3%). All of them had clinical parameters similar to those of migraine. In the HOH group headaches were global (33.3%), hemicranial (22.2%), frontal and occipital (22.2%), moderate (66.6%), severe (33.3%), and with sickness/vomiting (55.5%). 66.6% of them had clinical parameters similar to those of de novo chronic daily headache (NCDH). On carrying out a physical examination in all the patients, paresis of the abducent nerve was found in 31.2% and papilloedema in 93.7%. The average opening pressure was 27 cmH2O. Computerised axial tomography scanning revealed unspecific anomalies in 18.7% and they were also observed with magnetic resonance imaging in 31.2%. Associated pathologies were found in six patients (37%). Pharmacological treatment was effective in 93.8%. There were no relapses or sequelae. Idiopathic intracranial hypertension is a malady affecting young people, mainly females, with subacute headaches and symptoms similar to those of migraine and NCDH. A neurological abnormality suggestive of intracranial hypertension was found in 31.2-93.7% of patients.

Guillain-Barré syndrome, an acute polyradiculoneuropathy that presents with weakness and areflexia, is the most common cause of acute flaccid paralysis. In certain patients, respiratory failure is secondary to this disorder, eventually causing patients to require mechanical ventilation and experience additional complications due to diminished respiratory support and related mobility limitations. Prognoses for most of these cases are positive; treatment consists of basic support combined with plasmapheresis or administration of immunoglobulins. This study sought to describe the socio-demographic, clinical, laboratory and neurophysiological characteristics of patients with Guillain-Barré syndrome who were hospitalised in the Intensive Care Unit of the Neurological Institute of Colombia between 2006 and 2012. This study presents a case series. We surveyed 25 patients (32% female and 68% male) with Guillain-Barré syndrome and an average age of 54 years. Sixty per cent of these patients were admitted between days 3 and 7 after symptom onset; 64% had a history of respiratory infection and 20% had a history of intestinal infection. In addition, 84% of the patients presented with albuminocytological dissociation. We observed the following clinical subtypes of Guillain-Barré syndrome: inflammatory demyelinating polyneuropathy in 32%, acute motor-sensory axonal neuropathy in 28%, acute motor axonal neuropathy in 28%, and Miller Fisher syndrome in 12%. In this descriptive study of a group of critical care patients with GBS, results depended on patients' clinical severity at time of admission. Our findings are similar to results published in the international literature.

Myasthenia gravis is an antibody-mediated autoimmune disease. Approximately 10-15% of patients present with a thymoma, the presence of which is associated with greater severity of symptoms, myasthenic crisis, and irresponsiveness to front-line therapy. A thymectomy is recommended in young patients with generalized myasthenia gravis and in all patients presenting with thymoma. The patient was a 43-year-old woman, who first showed symptoms of myasthenic crisis in 2005 and presented with invasive thymoma managed with thymectomy and radiotherapy. In the subsequent three years, the patient presented with severe symptoms and two myasthenic crises that required mechanical ventilation and immunoglobulin treatment. Contrast chest computed tomography examinations showed no recurrence. Between 2009 and 2012, the patient experienced decreased symptom severity. In 2013, the patient presented with an exacerbation of symptoms; a contrast chest magnetic resonance scan showed a lesion in the anterior mediastinum, previously observed in 2011, suggestive of residual tissue as opposed to fibrosis. Regular management was started with immunoglobulins; a positron emission tomography scan was inconclusive, requiring a new resection, which showed no evidence of tumor recurrence. Patients with myasthenia gravis and those with myasthenia-related thymoma both share thymectomy as an element of treatment. However, following the procedure, exacerbation or reappearance of symptoms does not necessarily represent new alterations in the thymus.

The anterior opercular or biopercular syndrome is a cortical pseudobulbar palsy due to bilateral lesions of the anterior brain operculum. It is characterized by preservation of reflex function and automatic activity, without mental impairment. Two cases are reported herein and the relevant literature reviewed. The first case was a 73-year-old female with a history of a stroke occurring seven years previously, without sequelae in the interim. She presented with sudden loss of consciousness. The neurological examination showed a right facial central palsy and anarthria, with reflex acts such as smiling, blinking and yawning, not elicited by commands; she also had a right hemiparesis and walking impairment. A brain CT scan showed an old ischemic infarction in the region of the right medial cerebral artery. Because the right motor involvement did not correlate with the findings of the initial CT scan, another CT scan two days later showed an acute brain infarction in the vicinity of the left medial cerebral artery. The second case was an 8-year-old girl with mental retardation and impairment of verbal development, caused by of biopercular pachygyria. Facio-pharyngo-glosso-masticatory diplegia and volitional selective palsy of the oro-facial muscles was seen in both patients. The neuropsychological assessment showed cognitive, emotional and social interaction impairment in both cases -as part of the frontal convexity syndrome in the first case and of mental retardation in the second. The two patients had difficulty in mastication and swallowing. The prognosis for recovery of verbal capacity is poor, although generally most patients recover the ability to swallow.

A paraneoplastic syndrome characterized by neuropsychiatric symptoms, involuntary movements and seizures has been recently associated with antibodies targeting NMDA (N-methyl-D-aspartate) receptor in patients with an ovarian teratoma. Severe neurological impairment is frequent and treatment in the intensive care unit is often required because of ventilatory failure and life-threatening autonomic instability. Tumor removal is curative in many cases and neurological improvement is demonstrated shortly after surgery. Here we report on a patient with paraneoplastic encephalitis manifested by unconsciousness and coreo-athetosic movements related to NMDA receptor antibodies associated with an immature ovarian teratoma grade III. She made a complete recovery after oophorectomy, intravenous immunoglobulin and corticosteroids. Treatment of paraneoplastic syndromes is based on specific therapy for underlying tumor associated to immunomodulators. As in this case, anti-NMDA encephalitis may significantly improve after tumor removal and intra-venous immunoglobuline.

Resumen En el mundo y en Colombia la tuberculosis meníngea (TBM) es la causa más frecuente de las meningitis crónicas (1, 2). Las características clínicas y los hallazgos de laboratorio la sugieren pero no la confirman, requiriéndose el cultivo que es demorado y ...

Page 1. A CERTAIN FEELING OF HOMELESSNESS REMARKS ON ESTEBAN KROTZ'S 'ANTHROPOLOGIES OF THE SOUTH' Carlos A. Uribe* I am caught within a circle from which there is no escape: the less human societies ...

Spontaneous coronary artery dissection (SCAD) is a rare but important cause of acute coronary syndromes. SCAD can cause unstable angina, acute myocardial infarction, and sudden death. Predisposing factors include atherosclerosis, the peripartum period, and structural and inflammatory conditions affecting the arterial wall. The diagnosis of coronary dissection is usually made by coronary angiography. Prompt diagnosis and treatment of patients with dissection improves survival. Therapeutic options include medical therapy, percutaneous coronary intervention, and surgery. We present a series of patients with spontaneous coronary artery dissection at our institution. The etiology, pathogenesis, diagnosis, treatment, and prognosis of patients with coronary dissection are reviewed.

Brainstem encephalitis caused by Listeria monocytogenes is an uncommon form of central nervous system listeriosis; however, it is the most common presentation in immunocompetent individuals. Here, we describe an even more rare combination of rhombencephalitis with severe myelitis caused by L. monocytogenes in an immunocompetent patient. We report the case of a 21-year-old immunocompetent patient who consumed unpasteurized dairy products and experienced headache and vomiting that progressed to an impaired general condition, altered consciousness and ultimately death. The patient had presented to the Neurological Institute of Colombia (INDEC in Spanish) for consultation and was diagnosed with brainstem encephalitis and myelitis caused by Listeria monocytogenes . The differences between this particular case and those reported in the literature will be discussed. It is advisable to initiate antibiotic treatment for Listeria monocytogenes if a patient shows signs of brainstem compromise ...

We describe the case of a 34-year-old male patient, who was referred to the Instituto Neurológico de Colombia with probable Guillain-Barré syndrome, requiring intensive care management. The presence of cognitive alterations during his evolution, lead the team to reconsider the initial diagnosis for the Bickerstaff's brainstem encephalitis diagnosis. We aim to describe the patient's treatment and evolution, as well as a brief review and discussion.

Guillain-Barré syndrome, an acute polyradiculoneuropathy that presents with weakness and areflexia, is the most common cause of acute flaccid paralysis. In certain patients, respiratory failure is secondary to this disorder, eventually causing patients to require mechanical ventilation and experience additional complications due to diminished respiratory support and related mobility limitations. Prognoses for most of these cases are positive; treatment consists of basic support combined with plasmapheresis or administration of immunoglobulins. This study sought to describe the socio-demographic, clinical, laboratory and neurophysiological characteristics of patients with Guillain-Barré syndrome who were hospitalised in the Intensive Care Unit of the Neurological Institute of Colombia between 2006 and 2012. This study presents a case series. We surveyed 25 patients (32% female and 68% male) with Guillain-Barré syndrome and an average age of 54 years. Sixty per cent of these patients were admitted between days 3 and 7 after symptom onset; 64% had a history of respiratory infection and 20% had a history of intestinal infection. In addition, 84% of the patients presented with albuminocytological dissociation. We observed the following clinical subtypes of Guillain-Barré syndrome: inflammatory demyelinating polyneuropathy in 32%, acute motor-sensory axonal neuropathy in 28%, acute motor axonal neuropathy in 28%, and Miller Fisher syndrome in 12%. In this descriptive study of a group of critical care patients with GBS, results depended on patients' clinical severity at time of admission. Our findings are similar to results published in the international literature.