Prevalence and co-occurrence of lifestyle risk factors for non-communicable diseases according to sociodemographic characteristics among adults Chilean residents.

To examine the prevalence and co-occurrence of lifestyle risk factors for non-communicable diseases (NCDs) according to sociodemographic characteristics in Chilean residents. A cross-sectional study based on data from 5995 adults from the Chilean National Health Survey. The lifestyle risk factors included were physical inactivity, tobacco consumption, alcohol consumption, low fruits and vegetable consumption, and overweight/obesity. The most frequent risk factor was overweight/obesity (75.6%), followed by alcohol consumption (74.8%), low fruits and vegetable consumption (51.7%), physical inactivity (36.3%), and tobacco consumption (27.9%). Only 1.0% of the participants did not present any risk factor, while 9.6%, 30.4%, 34.0%, 20.3%, and 4.7% accumulated one, two, three, four, and five risk factors. Men (OR 1.56; 95% CI 1.18; 2.04), people who have secondary education (OR 1.59; 95% CI 1.20; 2.10), and those with lower household income (OR 1.39; 95% CI 1.09; 1.59) had higher odds of three or more risk factors. Associations were inverse for older adults (OR 0.57; 95% CI 0.41; 0.79) and rural geographic areas (OR 0.77; 95% CI 0.67; 0.89). The prevalence of risk factors for NCDs is fairly high in Chilean residents. Interventions may need to target these co-occurrences rather than emphasizing individual risk factors for NCDs. Interventions could further consider these co-occurrences as a potential target for population stratification.

Surgical management of hip prosthetic failure in metallosis: A case series and literature review.

Local and remote complications can be observed in hip prosthesis failures associated with metallosis. Structural changes in the periprosthetic bone and soft tissues may not always be precisely assessed preoperatively due to metal artifacts. The unpredictability of the damage extension, potentially leading to complex and insidious surgeries, requires the availability of alternative surgical plan(s) for the reconstruction of the joint. The aim of the study is to present and analyze, with the literature data support, practical tips for the revision of the prosthetic components, the management of ARMD and of intraoperative complications in the unusual scenario of metallosis.

[Pro-inflammatory serum cytokines in diabetic retinopathy]. / Citoquinas séricas proinflamatorias en retinopatía diabética.

BACKGROUND: Pro-inflammatory cytokines play an important role in diabetic retinopathy. There is conflicting evidence about their serum elevation in this condition and that they also may be possible serum inflammatory biomarkers of diabetic retinopathy. OBJECTIVE: To evaluate the presence of serum pro-inflammatory cytokines and acute phase reactants in the serum of patients with and without diabetic retinopathy. MATERIAL AND METHODS: Comparative case series with 36 patients divided into three groups were included: 12 patients with diabetes mellitus and diabetic retinopathy (group 1), 12 diabetic patients without diabetic retinopathy (group 2), and 12 healthy patients as a control group. Serum levels of the following pro-inflammatory cytokines were measured in all patients: TNF-α, IL-1ß and IL-6. Pro-inflammatory biomarkers measurements were also performed, such as erythrocyte sedimentation rate and C-reactive protein. RESULTS: The levels of TNF-α and IL-6 were higher in group 1 (TNF-α: 19.4 ± 10.9 pg/ml, IL-6: 5.75 ± 7 pg/ml) compared to the other two groups, although the difference was statistically significant only in the case of TNF-α (group 1: 19.4 ± 10.9 pg/ml, group 2: 14 ± 4.3 pg/ml and control: 8.49 ± 3.69 pg/ml, p = 0.001). There were no differences among pro-inflammatory biomarkers such as erythrocyte sedimentation rate and C reactive protein. among the three groups (p > 0.05). CONCLUSIONS: Pro-- inflammatory serum cytokine levels were higher in the diabetes mellitus with diabetic retinopathy group. Larger studies are warranted to establish the real impact of this finding.

Mielitis transversa en síndrome de Sjögren y lupus eritematoso sistémico: presentación de 3 casos / Myelitis transverse in Sjögren´s syndrome and systemic Lupus erythematosus: presentation of 3 cases

La mielitis transversa es una inflamación focal poco frecuente de la médula espinal. Su etiología es múltiple y entre ellas se encuentran las enfermedades autoinmunes, incluyendo principalmente el lupus eritematoso sistémico y el síndrome de Sjögren. Su presentación clínica puede ser de forma aguda o subaguda, con peor pronóstico en la mielitis transversa aguda. Un diagnóstico precoz y tratamiento intensivo desde el inicio es de gran importancia en la evolución de este tipo de pacientes. Presentamos 3 casos con mielitis transversa asociados a enfermedades autoinmunes y discutimos sus distintas manifestaciones clínicas, la asociación a autoanticuerpos, las imágenes radiológicas, el tratamiento y el pronóstico (AU)

Transverse myelitis is a rare focal inflammation of the spinal cord. Multiple etiologies have been identified including autoimmune diseases, mainly systemic lupus erythematosus and Sjögren’ syndrome. It can occur in an acute or subacute clinical onset, with the acute presentation having a worse prognosis. An early diagnosis and intensive treatment are important features recommended in these patients. We present three cases with transverse myelitis associated with autoimmune diseases. We discuss different clinical manifestations, association with autoantobodies, radiologic findings, and therapeutic and prognostic issues (AU)

Myelitis transverse in Sjögren's syndrome and systemic lupus erythematosus: presentation of 3 cases.

Transverse myelitis is a rare focal inflammation of the spinal cord. Multiple etiologies have been identified including autoimmune diseases, mainly systemic lupus erythematosus and Sjögren' syndrome. It can occur in an acute or subacute clinical onset, with the acute presentation having a worse prognosis. An early diagnosis and intensive treatment are important features recommended in these patients. We present three cases with transverse myelitis associated with autoimmune diseases. We discuss different clinical manifestations, association with autoantobodies, radiologic findings, and therapeutic and prognostic issues.

Medicamentos biocomparables en México: la postura del Colegio Mexicano de Reumatología, 2012 / Biosimilar drugs in Mexico: Position of the Mexican College of Rheumatology, 2012

Los medicamentos biotecnológicos (MBT) son moléculas complejas cuyo proceso de elaboración impide replicar con gran exactitud la sustancia original, por lo que no existe una equivalencia absoluta entre el fármaco original (innovador) y el biocomparable. Los MBT han probado su eficacia en diversas afecciones reumáticas, aunque su alto coste impide su utilización en muchos pacientes. Diversas patentes de medicamentos biotecnológicos han expirado o expirarán próximamente, detonando así el desarrollo de fármacos estructuralmente similares y probablemente con eficacia y seguridad comparable a los medicamentos innovadores, aunque estas características deben ser probadas. La Ley General de Salud Mexicana actual contempla el registro de estos medicamentos para su utilización en nuestro país. Este documento es una reflexión de miembros del Colegio Mexicano de Reumatología, farmacólogos e investigadores en epidemiología, en conjunción con nuestras autoridades sanitarias, sobre los estudios científicos necesarios de los biocomparables previos y posterior a su incursión en el mercado mexicano (AU)

Biotechnological drugs (BTDs) are complex molecules whose manufacturing process precludes the ability to identically reproduce the structure of the original product, and therefore there cannot be an absolute equivalence between the original (innovative) medication and its biosimilar counterpart. BTDs have been proven useful in the treatment of several rheumatic diseases, however their high cost has prevented their use in many patients. Several BTD patents have expired or are close to expire, triggering the development of structurally similar drugs with efficacy and safety profiles comparable to the innovative compound; however, these must be evaluated through evidence based medicine. The Mexican General Health Law contemplates the registry of these biosimilar drugs for their use in our country. This document is a forethought from members of the Mexican College of Rheumatology, pharmacologists, and epidemiologists, in accordance with Mexican health authorities regarding the necessary scientific evidence required to evaluate the efficacy and safety of biosimilar drugs before and after their arrival to the Mexican market (AU)

Biosimilar drugs in Mexico: position of the Mexican College of Rheumatology, 2012.

Biotechnological drugs (BTDs) are complex molecules whose manufacturing process precludes the ability to identically reproduce the structure of the original product, and therefore there cannot be an absolute equivalence between the original (innovative) medication and its biosimilar counterpart. BTDs have been proven useful in the treatment of several rheumatic diseases, however their high cost has prevented their use in many patients. Several BTD patents have expired or are close to expire, triggering the development of structurally similar drugs with efficacy and safety profiles comparable to the innovative compound; however, these must be evaluated through evidence based medicine. The Mexican General Health Law contemplates the registry of these biosimilar drugs for their use in our country. This document is a forethought from members of the Mexican College of Rheumatology, pharmacologists, and epidemiologists, in accordance with Mexican health authorities regarding the necessary scientific evidence required to evaluate the efficacy and safety of biosimilar drugs before and after their arrival to the Mexican market.

Validity of the COPCORD core questionnaire as a classification tool for rheumatic diseases.

OBJECTIVE: Rheumatic diseases are vastly underdiagnosed and undertreated, particularly among minorities and those of low socioeconomic status. The WHO-ILAR Community Oriented Program in the Rheumatic Diseases (COPCORD) advocates screening of musculoskeletal complaints in the community. The objective of this study was to evaluate the performance of the COPCORD Core Questionnaire (CCQ) as a diagnostic tool for rheumatic diseases. METHODS: We conducted a cross-sectional study designed in parallel with a large COPCORD survey in Mexico. A subsample of 17,566 questionnaires, selected from 4 of the 5 states included in a national COPCORD survey were included in the analysis as a diagnostic test to evaluate sensitivity, specificity, receiver operating characteristics curve (ROC), and positive likelihood ratio (LR+) of the CCQ as a case-detection tool for rheumatic diagnosis and for the most frequent diagnoses identified in the survey, osteoarthritis, regional rheumatic pain syndromes, and rheumatoid arthritis (RA). Logistic regression with the questions with LR+ ≥ 1 was performed to identify the strength of association (OR) for each question. RESULTS: Pain in the last 7 days, high pain score (> 4), and previous diagnosis were the questions with highest LR+ for diagnosis, and for diagnosis of RA treatment with NSAID. The variables that contributed most to the model were pain in the last 7 days (OR 2.0, 95% CI 1.8-2.3), NSAID treatment (OR 3.3, 95% CI 3.0-3.7), a high pain score (OR 1.15, 95% CI 1.13-1.17), and having a previous diagnosis (OR 1.4, 95% CI 1.3-1.6). These 4 questions had R(2) = 0.24, p < 0.01, for detection of any rheumatic diagnosis. The single variable that explains 16% (OR 1.33, 95% CI 1.31-134) of variance was a high pain score in the last 7 days. CONCLUSION: Some variables were identified in the CCQ that could be combined in a brief version for case detection of rheumatic diseases in community surveys. The validity of this proposal has to be tested against the original version.

Genetically determined Amerindian ancestry correlates with increased frequency of risk alleles for systemic lupus erythematosus.

OBJECTIVE: To assess whether genetically determined Amerindian ancestry predicts increased presence of risk alleles of known susceptibility genes for systemic lupus erythematosus (SLE). METHODS: Single-nucleotide polymorphisms (SNPs) within 16 confirmed genetic susceptibility loci for SLE were genotyped in a set of 804 Mestizo lupus patients and 667 Mestizo healthy controls. In addition, 347 admixture informative markers were genotyped. Individual ancestry proportions were determined using STRUCTURE. Association analysis was performed using PLINK, and correlation between ancestry and the presence of risk alleles was analyzed using linear regression. RESULTS: A meta-analysis of the genetic association of the 16 SNPs across populations showed that TNFSF4, STAT4, ITGAM, and IRF5 were associated with lupus in a Hispanic Mestizo cohort enriched for European and Amerindian ancestry. In addition, 2 SNPs within the major histocompatibility complex region, previously shown to be associated in a genome-wide association study in Europeans, were also associated in Mestizos. Using linear regression, we predicted an average increase of 2.34 risk alleles when comparing an SLE patient with 100% Amerindian ancestry versus an SLE patient with 0% Amerindian ancestry (P < 0.0001). SLE patients with 43% more Amerindian ancestry were predicted to carry 1 additional risk allele. CONCLUSION: Our results demonstrate that Amerindian ancestry is associated with an increased number of risk alleles for SLE.

Prevalence of BRCA1 and BRCA2 mutations in breast cancer patients from Cuba.

The contribution of BRCA1 and BRCA2 to breast cancer incidence in Cuba has not yet been explored. In order to estimate the proportion of breast cancers due to BRCA1 and BRCA2 mutations in Cuba, and to identify possible Cuban founder mutations, we conducted a study of unselected breast cancer patients from Havana, Cuba. We enrolled 336 women with breast cancer from a large public hospital in the city. A family history of cancer was obtained from each patient and a blood sample was processed for DNA analysis. Mutations in BRCA1 and BRCA2 were sought using a combination of techniques, but all mutations were confirmed by direct sequencing. We were able to successfully complete testing on samples from 307 women. Among these, eight mutations were identified (seven in BRCA2 and one in BRCA1) representing 2.6% of the total, including 10% of familial cases and 10% of cases under age forty. One BRCA2 mutation (c.3394C > T) was found in two women, but no clear example of a founder mutation was identified. In summary, BRCA1 and BRCA2 mutations are not uncommon in Cuban women with breast cancer, but the absence of founder mutations precludes the development of a rapid and inexpensive clinical screening test.

Prescription rheumatology practices among Mexican specialists.

BACKGROUND: We undertook this study to describe prescription practices and the degree of disease control in a large sample of patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS) treated by rheumatologists in Mexico. METHODS: Board-certified Mexican rheumatologists across the country were asked to assess consecutive RA and AS patients; 1208 patients completed a self-administered questionnaire with information on demographics, disease duration, co-morbidity, treatment, pain, disability and a validated Spanish version of instruments to measure physical function and quality of life. RESULTS: Of the 1096 RA patients, 88.1% were treated with nonsteroidal anti-inflammatory drugs (NSAIDs), 1020 (93.3%) with disease-modifying anti-rheumatic drugs (DMARDs), 365 (33.4%) with steroids, and 70 (6.4%) with biological agents. Their mean Health Assessment Questionnaire Disability Index (HAQ-Di) score was 1.21+/-0.80, Disease Activity Index, 28 joint count (DAS 28) 3.9+/-1.29, and Rheumatoid Arthritis Disease Activity Index (RADAI), 3.94+/-2.01. Regarding the 112 AS patients, 110 (98.2%) received NSAIDs, 90 (80.4%) were on DMARDs, 11 (9.8%) took steroids, and 11 (9.8%) received biological agents, their functional status shown as Bath Ankylosing Spondylitis Functional Index (BASFI) score of 4.4+/-2.5. Among the 1110 DMARD users, only 64 received one drug, and a great proportion used two or more DMARDs; 81 subjects (16.2%) were on biological agents, in any combination. RA patients more commonly used methotrexate, 791 (72%) cases, and hydroxychloroquine. Taking into account their diagnosis, the combination most prescribed was NSAIDs plus DMARDs in 660 subjects (54.7%). CONCLUSIONS: DMARDs in combination with other drug are the most frequently prescribed therapeutic scheme for RA and AS patients. These schemes used for both conditions by Mexican rheumatologists are in line with current international recommendations.

Costs of the standard rheumatology care in active rheumatoid arthritis patients seen in a tertiary care center in Mexico City

Objetivo: Determinar en el contexto de un ensayo clínico los costes de la asistencia sanitaria convencional en los pacientes con artritis reumatoide (AR) activa atendidos en un centro de nivel terciario de Ciudad de México. Analizar las relaciones existentes entre los costes económicos y las unidades de utilidad en los pacientes con las características señaladas. Pacientes y métodos: Este análisis económico se realizó en el contexto de un ensayo clínico efectuado con un seguimiento de 48 semanas en un centro asistencial de nivel terciario en Ciudad de México. En el ensayo clínico se comparó la eficacia de los ácidos grasos omega-3 con la del placebo en pacientes con AR activa que también recibían asistencia reumatológica convencional. Se determinaron los costes económicos de las consultas médicas, de las pruebas diagnósticas complementarias y de los tratamientos farmacológicos. También se determinaron otros costes directos. Además, se analizaron varios contextos hipotéticos en los que se hubieran realizado menos consultas médicas y menos pruebas diagnósticas complementarias que las que se llevaron a cabo en el ensayo clínico. La utilidad se evaluó a través del Health Utility Index. Se calculó un cociente costeutilidad utilizando como factor de comparación la puntuación de utilidad inicial. Se realizó un análisis estadístico de tipo descriptivo. Resultados: Participaron en el estudio 90 pacientes con AR (83 mujeres [92%], con una edad [X ± DE] de 43,2 ± 14,2 años y con una duración de la enfermedad de 3,3 ± 4,6 meses). En los análisis se utilizaron los datos correspondientes a 88 pacientes. Los costes directos totales fueron de 152.704,11 dólares estadounidenses de 2005, correspondientes a la asistencia médica (78.386,43 dólares estadounidenses de 2005, 51,33%), al tratamiento medicamentoso (39.339,05 dólares estadounidenses de 2005, 25,76%) y a otros costes directos (24.978,18 dólares estadounidenses de 2005, 22, 91%). En los contextos hipotéticos en los que se consideró un número menor de consultas médicas y de pruebas diagnósticas complementarias, en comparación con el que tuvo lugar el ensayo clínico, los costes directos totales oscilaron entre 39.507,4 y 103.880,06 dólares estadounidenses de 2005. La mejora de los pacientes tuvo un valor medio de 0,18 unidades de utilidad en una escala de 0-1, equivalente a 0,18 años de vida con ajuste de la calidad (QALY, quality adjusted life-years). Los cocientes coste-utilidad oscilaron entre 2.494,1 y 9.640,38 dólares estadounidenses de 2005 por QALY en los contextos analizados. Conclusiones: Los costes directos de la asistencia convencional realizada en México sobre los pacientes con AR en los contextos analizados son sustanciales tanto desde el punto de vista social como económico. El coste por QALY ganado es elevado(AU)

Objective: To assess the costs of standard care in patients with active rheumatoid arthritis (RA) seen in a tertiary care center in México City in the context of a clinical trial. To analyze the relationship between costs and utility units obtained by the patients in this scenario. Patients and methods: This economic evaluation was performed during a clinical trial with a 48-week followup in a tertiary care center in México City. The trial compared the efficacy of omega-3 fatty acids versus placebo in patients with active RA who also received standard rheumatology care. The costs of medical consultations, complementary tests and drugs were assessed. Other direct costs were also measured. Hypothetical scenarios with fewer medical consultations and complementary tests than those in the clinical trial were also analyzed. Utilities were assessed by the Health Utility Index. A cost-utility ratio was calculated using the baseline utilities score as comparator. A descriptive statistical analysis was performed. Results: Ninety RA patients (83 women [92%], age [X ± SD] 43.2 ± 14.2 years with disease duration of 3.3 ± 4.6 years) were included. Data from 88 patients were analyzed. The total direct costs were 152,704.11 US$ 2005 divided into medical attention (78,386.43 US$ 2005, 51.33%), drugs (39,339.5 US$ 2005, 25.76%) and other direct costs (34,978.18 US$ 2005. 22.91%). In scenarios with fewer medical consultations and complementary tests than those in the clinical trial, the total direct costs ranged from 39,507.4 to 103,880.6 US$ 2005. Patients improved by a mean of 0.18 utility units on a 0-1 scale equivalent to 0.18 quality adjusted lifeyears (QALYs). The cost-utility ratios ranged from 2,494.1 to 9,640.38 US$ 2005 per QALY in the scenarios analyzed. Conclusions: The direct costs of the standard care of RA in the scenarios analyzed are substantial in the social and economic context of Mexico. The cost per gained QALY is high(AU)

Costs of the standard rheumatology care in active rheumatoid arthritis patients seen in a tertiary care center in Mexico City.

OBJECTIVE: To assess the costs of standard care in patients with active rheumatoid arthritis (RA) seen in a tertiary care center in México City in the context of a clinical trial. To analyze the relationship between costs and utility units obtained by the patients in this scenario. PATIENTS AND METHODS: This economic evaluation was performed during a clinical trial with a 48-week followup in a tertiary care center in México City. The trial compared the efficacy of omega-3 fatty acids versus placebo in patients with active RA who also received standard rheumatology care. The costs of medical consultations, complementary tests and drugs were assessed. Other direct costs were also measured. Hypothetical scenarios with fewer medical consultations and complementary tests than those in the clinical trial were also analyzed. Utilities were assessed by the Health Utility Index. A cost-utility ratio was calculated using the baseline utilities score as comparator. A descriptive statistical analysis was performed. RESULTS: Ninety RA patients (83 women [92%], age [X ± SD] 43.2 ± 14.2 years with disease duration of 3.3 ± 4.6 years) were included. Data from 88 patients were analyzed. The total direct costs were 152,704.11 US$ 2005 divided into medical attention (78,386.43 US$ 2005, 51.33%), drugs (39,339.5 US$ 2005, 25.76%) and other direct costs (34,978.18 US$ 2005. 22.91%). In scenarios with fewer medical consultations and complementary tests than those in the clinical trial, the total direct costs ranged from 39,507.4 to 103,880.6 US$ 2005. Patients improved by a mean of 0.18 utility units on a 0-1 scale equivalent to 0.18 quality adjusted lifeyears (QALYs). The cost-utility ratios ranged from 2,494.1 to 9,640.38 US$ 2005 per QALY in the scenarios analyzed. CONCLUSIONS: The direct costs of the standard care of RA in the scenarios analyzed are substantial in the social and economic context of Mexico. The cost per gained QALY is high.

Participación y vigilancia ciudadana en la actividad minera: implicancias en el derecho a la salud

"Desde una visión holística, los autores proponen el medio ambiente como un espacio de realización del derecho a la salud, pues los derechos humanos, la salud pública y el medio ambiente constituyen filosóficamente una totalidad indivisible.[AU]"

Multiple cyclin-dependent kinases signals are critical mediators of ischemia/hypoxic neuronal death in vitro and in vivo.

The mechanisms involving neuronal death after ischemic/hypoxic insult are complex, involving both rapid (excitotoxic) and delayed (apoptotic-like) processes. Recent evidence suggests that cell cycle regulators such as cyclin-dependent kinases are abnormally activated in neuropathological conditions, including stroke. However, the function of this activation is unclear. Here, we provide evidence that inhibition of the cell cycle regulator, Cdk4, and its activator, cyclinD1, plays critical roles in the delayed death component of ischemic/hypoxic stress by regulating the tumor suppressor retinoblastoma protein. In contrast, the excitotoxic component of ischemia/hypoxia is predominately regulated by Cdk5 and its activator p35, components of a cyclin-dependent kinase complex associated with neuronal development. Hence, our data both characterize the functional significance of the cell cycle Cdk4 and neuronal Cdk5 signals as well as define the pathways and circumstances by which they act to control ischemic/hypoxic damage.

[Secondary Raynaud's syndrome: skin blood flow decrease between the ischemic episodes and prolongation of the vasoconstriction during the respiratory maneuvers]. / Síndrome de Raynaud secundario: disminución del flujo sanguíneo de la piel entre los episodios isquémicos y prolongación de la vasoconstricción con las maniobras respiratorias.

UNLABELLED: The Raynaud's syndrome is an episodic skin ischemia manifested by pallor, cyanosis and erythema of the fingers in response to cold or emotional stress. The exact pathophysiology is unknown but it has been hypothetised that may be due to an autonomic alteration in the sympathetic innervation of skin blood vessels. OBJECTIVE: To study the changes of heart rate and skin blood flow (SBF) in healthy subjects and in patients with secondary Raynaud's syndrome during different respiratory maneuvers: 1. spontaneous respiration; 2. rhythmic respirations (RR), 3. sudden inspirations (SI), and 4. Valsalva maneuver (VM). METHODS: We studied 22 healthy subjects and 22 patients with secondary Raynaud's syndrome. The variables measured were: 1) RR intervals; 2) amplitudes of SBF; 3) percentage of decrease of SBF; 4) latency of the maximum decrease of SBF. RESULTS: In all patients with secondary Raynaud's syndrome the SBF was decreased basally during spontaneous rations and during all respiratory maneuvers (p < 0.001). The mean latency of recovery of the SBF was prolonged during sudden deep inspiration. The patients with Raynaud also had significant basal tachycardia at rest (p < 0.003). CONCLUSIONS: The basal skin blood flow during spontaneous respirations and in asymptomatic periods is decreased in patients with Raynaud's syndrome; this may be related to endothelial arterioral damage. The SBF was also significantly decreased dynamically during sudden inspirations (SI), rhythmic breathing (RR) and Valsalva maneuver (VM). This dynamic change suggests sympathetic hyperactivity.

Síndrome de Raynaud secundario: disminución del flujo sanguíneo de la piel entre los episodios isquémicos y prolongación de la vasoconstricción con las maniobras respiratorias / Secondary Raynaud's syndrome: skin blood flow decrease between the ischemic episodes and prolongation of the vasoconstriction during the respiratory maneuvers

El síndrome de Raynaud se caracteriza por isquemia cutánea digital episódica, manifestada por palidez, cianosis y rubor de los dedos de manos y pies expuestos al frío o cuando el paciente está sujeto a un estrés emocional. No se conoce el mecanismo fisiopatológico exacto; la hipótesis más invocada es una alteración autonómica en la inervación simpática de los vasos sanguíneos de la piel. Objetivo: Estudiar los cambios de la frecuencia cardíaca y el flujo sanguíneo de la piel (FSP) en sujetos sanos y en pacientes con síndrome de Raynaud durante las siguientes condiciones: 1. respiración espontánea (RE), 2. respiración rítmica (RR), 3. inspiración profunda repentina (IPR), 4. maniobra de Valsalva (MV). Método: Se estudiaron 22 sujetos sanos y 22 pacientes con síndrome de Raynaud secundario. Las variables medidas fueron: 1. intervalo R-R; 2. amplitud de FSP; 3. porcentaje de disminución de FSP; 4. latencia de la máxima disminución del FSP. Resultados: Los pacientes con síndrome de Raynaud presentaron mayor taquicardia basal. La amplitud del FSP se encontró disminuido durante la respiración espontánea y durante las maniobras respiratorias (P < 0.001). La vasoconstricción estuvo prolongada ya que la latencia promedio de recuperación del FSP estuvo prolongada en IPR y MV en comparación de los sujetos controles. Conclusión: La amplitud del FSP basal está disminuida en los pacientes con síndrome de Raynaud, durante períodos asintomáticos; esto sugiere daño endotelial. También se encontró disminuido con las diversas maniobras respiratorias (RR, IPR y MV). Este cambio dinámico sugiere hiperactividad simpática hacia los vasos sanguíneos de la piel.

The Raynaud's syndrome is an episodic skin ischemia manifested by pallor, cyanosis and erythema of the fingers in response to cold or emotional stress. The exact pathophysiology is unknown but it has been hypothetised that may be due to an autonomic alteration in the sympathetic innervation of skin blood vessels. Objective: To study the changes of heart rate and skin bloodflow (SBF) in healthy subjects and in patients with secondary Raynaud's syndrome during different respiratory maneuvers: 1. spontaneous respiration; 2. rhythmic respirations (RR), 3. sudden inspirations (SI), and 4. Valsalva maneuver (VM). Methods: We studied 22 healthy subjects and 22 patients with secondary Raynaud's syndrome. The variables measured were: 1) RR intervals; 2) amplitudes of SBF; 3) percentage of decrease of SBF; 4) latency of the maximum decrease of SBF. Results: In all patients with secondary Raynaud's syndrome the SBF was decreased basally during spontaneous respirations and during all respiratory maneuvers (p < 0.001). The mean latency of recovery of the SBF was prolonged during sudden deep inspiration. The patients with Raynaud also had significant basal tachycardia at rest (p < 0.003). Conclusions: The basal skin blood flow during spontaneous respirations and in asymptomatic periods is decreased in patients with Raynaud's syndrome; this may be related to endothelial arterioral damage. The SBF was also significantly decreased dynamically during sudde3n inspirations (SI), rhythmic breathing (RR) and Valsalva maneuver (VM). This dynamic change suggests sympathetic hyperactivity.

Identification of regions of the tomato gamma-glutamyl kinase that are involved in allosteric regulation by proline.

The first step of proline biosynthesis is catalyzed by gamma-glutamyl kinase (GK). To better understand the feedback inhibition properties of GK, we randomly mutagenized a plasmid carrying tomato tomPRO1 cDNA, which encodes proline-sensitive GK. A pool of mutagenized plasmids was transformed into an Escherichia coli GK mutant, and proline-overproducing derivatives were selected on minimal medium containing the toxic proline analog 3,4-dehydro-dl-proline. Thirty-two mutations that conferred 3,4-dehydro-dl-proline resistance were obtained. Thirteen different single amino acid substitutions were identified at nine different residues. The residues were distributed throughout the N-terminal two-thirds of the polypeptide, but 9 mutations affecting 6 residues were in a cluster of 16 residues. GK assays revealed that these amino acid substitutions caused varying degrees of diminished sensitivity to proline feedback inhibition and also resulted in a range of increased proline accumulation in vivo. GK belongs to a family of amino acid kinases, and a predicted three-dimensional model of this enzyme was constructed on the basis of the crystal structures of three related kinases. In the model, residues that were identified as important for allosteric control were located close to each other, suggesting that they may contribute to the structure of a proline binding site. The putative allosteric binding site partially overlaps the dimerization and substrate binding domains, suggesting that the allosteric regulation of GK may involve a direct structural interaction between the proline binding site and the dimerization and catalytic domains.

Hidatidosis hepática: abordaje laparoscópico / Hepatic hydatidosis: laparoscopic approach

Se propone la solución quirúrgica de la hidatidosis hepática mediante laparoscopía. Se describen 3 casos operados con el método, 2 de ellos tratados en forma completa con evolución normal, y uno convertido a laparotomía clásica por la ubicación posterior de uno de los quistes, que complicó en postoperatorio con colección subfrénica, resuelta con punción eco-guiada. El procedimiento presenta las ventajas conocidas de la cirugía laparoscópica, a las que se suma la posibilidad de movilizar el hígado, tratar la cápsula y el contenido de los quistes, diagnosticar y tratar comunicaciones con la vía biliar principal, siempre con la posibilidad "stand by" de convertir, y todo en un cotexto de mínima agresión, menor posibilidad de contaminación, daño nulo a la pared abdominal e índice aceptable de confort postoperatorio. Se concluye en aconsejar iniciar con laparoscopía diagnóstica cada cirugía frente a la presunción de quiste hidatídico de hígado