Safety and efficacy of a mesenchymal stem cell intramammary therapy in dairy cows with experimentally induced Staphylococcus aureus clinical mastitis.

Although, antibiotics are effective in the treatment of bovine mastitis, they do not address the regeneration of mammary glandular tissue and have been associated to the increment in antimicrobial resistance worldwide. Considering the necessity of alternative therapies for this disease of high economic impact and the reported regenerative and antibacterial effects of mesenchymal stem cell (MSCs), we evaluated the safety and efficacy of an allogenic MSC-based intramammary therapy in dairy cows with experimentally induced Staphylococcus aureus clinical mastitis. In a safety trial, heifers were inoculated intramammarily with a 2.5 × 107-suspension of bovine fetal AT-MSCs on experimental days 1 and 10. Animals were evaluated clinically on a daily basis during a 20-day experimental period and blood samples were collected for hemogram determination and peripheral blood leukocytes (PBLs) isolation. In an efficacy trial, Holstein Friesian cows were inoculated with S. aureus and treated intramammarily with vehicle (NEG; days 4 and 10), antibiotics (ATB; days 4 and 5) or a suspension of 2.5 × 107 AT-MSCs (MSC; days 4 and 5). Cows were clinically evaluated daily and milk samples were collected for somatic cell count (SCC) and colony forming units (CFU). Blood samples were collected for serum haptoglobin and amyloid A determination. Intramammary administration of two doses of bovine fetal AT-MSCs in healthy cows did not induce changes in clinical or hematological variables, and gene expression profiles in PBLs associated to activation (CD4, CD8, CD25, CD62L and CD69) and proinflammatory cytokines (CCL2, CCL5, IL2, CXCL3, IFNγ, and TNFα). Quarters of MSC group of cows had similar SCC log/mL in milk compared to infected quarters of ATB or NEG cows. However, quarters of MSC cows had lower CFU log/mL in milk compared to quarters of NEG cows. Intramammarily inoculation of repeated doses of 2.5 × 107 allogenic AT-MSCs did not induce clinical or immunological response in healthy cows. Moreover, MSC-intramammary treatment reduced bacterial count in milk of cows with S. aureus clinical mastitis compared to untreated cows. This work provides initial evidence for the safety and efficacy of an allogenic MSC-based intramammary therapy for the treatment of bovine mastitis.

Risk factors associated with congenital defects that alter hearing or vision in children born in the city of Bogotá between 2002 and 2016.

INTRODUCTION: Congenital defects affecting the auditory and visual capacity of newborns represent a public health problem as they result in substantial disability, directly impacting the quality of life of newborns and their families. OBJECTIVE: To evaluate risk factors associated with congenital defects that alter hearing or vision in newborns in the city of Bogotá between 2002 and 2016. METHOD: Data from the Bogotá Birth Defects Surveillance and Follow-up Program was used, which consolidated data regarding 167 ECLAMC study (Estudio Colaborativo Latino Americano de Malformaciones Congénitas, in spanish) variables in a case-control design to identify risk factors for birth defects after parents provided signed informed consent. Cases were defined as any newborn (alive or stillborn) with a weight greater than 500 g with any visual or hearing abnormality. Controls were defined as newborn in the same hospital and month with no birth defects. Groups were formed according to the case presentation as follows: isolated eye anomaly, isolated ear anomaly, polymalformative, syndromic, and teratogenic. RESULTS: In total, 402,657 births were reviewed, of which 968 cases had some congenital defects that alter hearing or vision. An association was found between the presence of defects and prematurity, as well as between syndromic cases and increasing maternal age. When comparing cases and controls with the risk of having a birth defect, multiparity had an odds ratio (OR) of 1.47 (95% CI: 1.27-1.71), acute respiratory infection had an OR of 2.41 (95% CI: 1.04-5.58), low maternal education level had an OR of 1.34 (95% CI:1.10-1.62), low paternal education had an OR of 1.42, (95% CI:1.17-1.73), manual labor in the maternal occupation had an OR of 1.31 (95% CI:1.03-1.67), and a history of congenital anomalies in the family had an OR of 1.55 (95% CI:1.19-2.00). CONCLUSION: This research allowed the identification of epidemiological data and significant risk factors for congenital defects that alter hearing or vision in the population of Bogotá.

Teamwork: relevance and interdependence of interprofessional education.

OBJECTIVE: Determine the perception of university students regarding interprofessional and interdependent work between team members in their inclusion in primary care. METHODS: Analytical cross-sectional study. The sampling had a probabilistic, stratified random type with 95% confidence and 5% margin of error. Seven-hundred and four students of Public Universities in Santiago (Chile) answered self-administered questionnaire. RESULTS: Ninety-seven point eight of students say that interprofessional work is important; 27.1% of them declare that their university did not seem to show that their study plans were important. The professionals listed as most important in teams are physicians and nurses. CONCLUSIONS: Spaces for development and institutional support are key elements to promote interprofessional work. If this competence can involve each academic unit in their different formative spaces there will be a significant contribution to said promotion. Teamwork is a pending task. OBJETIVO: Determinar la percepción de estudiantes universitarios respecto al trabajo interprofesional e interdependencia entre los miembros del equipo en su inserción en la atención primaria. MÉTODOS: Estudio de tipo analítico y transversal. El muestreo fue de tipo aleatorio, probabilístico estratificado con un 95% de confianza y un 5% de margen de error. Se utilizó un cuestionario auto-administrado en 704 estudiantes de Universidades del Estado en Santiago de Chile. RESULTADOS: Un 97,8% de los estudiantes opinan que el trabajo interprofesional es importante; un 27,1% de ellos declara que su universidad no le ha entregado importancia en sus planes de estudios. Los profesionales mencionados como más importantes en el equipo son los médicos y enfermeras. CONCLUSIONES: Espacios de desarrollo y respaldo institucional son elementos claves para promover el trabajo interprofesional. Que esta competencia logre involucrar a cada unidad académica en sus diferentes espacios formativos será un aporte significativo en aquello. Trabajo en equipo es una tarea pendiente.

Trabajo en equipo: relevancia e interdependencia de la educación interprofesional / Teamwork: relevance and interdependence of interprofessional education

La educación médica se ha enfocado, históricamente, en el desempeño individual de los profesionales de la salud. Sin embargo, ante los cambios en el foco, estructura y necesidades de los sistemas de atención en salud, el foco se ha redirigido hacia el trabajo en equipo. Esta concepción implica una acción coordinada, llevada a cabo por dos o más individuos, lo que implica metas acordadas en conjunto, y exige entendimiento claro y respeto de los roles y las funciones de cada miembro. El trabajo en equipo, más que un fin, es un proceso y requiere la habilidad de trabajar como colegas, en vez de superior-subordinado. En este sentido, se entiende por multiprofesionalismo al trabajo común realizado por profesionales de las diferentes categorías, en las que su contribución individual conduce a un producto final que satisface los requerimientos únicos de cada parte en la solución de los problemas identificados. Tanto la construcción colectiva del trabajo a realizar por el equipo multidisciplinario cuanto las posibilidades de incorporar la atención a las prácticas profesionales, indican la necesidad de identificar y desarrollar dimensiones comunicativas en los sujetos involucrados en el cuidado (trabajadores y usuarios). Los equipos multidisciplinarios deben superar los acuerdos y articulaciones centradas solo en las relaciones. La Organización Mundial de la Salud señala que la práctica colaborativa optimiza los resultados de la atención en salud entregando una atención integral a los pacientes, sus familias, cuidadores y comunidades. Los profesionales preparados para la práctica colaborativa han aprendido a trabajar en un equipo interprofesional mediante entrenamiento efectivo en educación interprofesional; esta educación ocurre cuando estudiantes de dos o más profesiones aprenden sobre, de y entre ellos mismos para permitir una colaboración efectiva. (AU)

Effect of awareness through movement on the head posture of bruxist children.

The aim of this study was to evaluate the effectiveness of physiotherapy to improve the head posture and reduce the signs of bruxism in a group of bruxist children. A single-blind randomized clinical trial was performed. All the subjects were 3- to 6-year old, had complete primary dentition, dental and skeletal class I occlusion and were classified as bruxist according to the minimal criteria of the ICSD for bruxism. For each child, a clinical, photographic and radiographic evaluation of the head and cervical posture were realized with standardized techniques. The children were randomized in an experimental (n = 13) and a control (n = 13) group. A physiotherapeutic intervention was applied to the children of the experimental group once a week, until 10 sessions were completed. Afterwards, the cephalogram and the clinical and photographic evaluation of the head posture were measured again. The data were analysed with the t-test and Mann-Whitney test. The subjects of the experimental group showed statistically significant improvement in the natural head posture. The physiotherapeutic intervention showed to be efficient to improve the head posture at the moment of measurement in the studied children. The relationship between bruxism and head posture, if exists, seems to be worthwhile to examine.

Molecular studies in the GJB2 gene (Cx26) among a deaf population from Bogotá, Colombia: results of a screening program.

OBJECTIVE: We conducted a pilot screening program to define the prevalence of non-syndromic deafness and establish the frequency of mutations in the GJB2 gene (Cx26) in a population of children with congenital deafness in Bogotá, Colombia. METHOD: From a cohort of 731 children in 8 institutions for the deaf, we identified 322 (44%) with presumed non-syndromic deafness. These were invited to a more detailed evaluation, but 46 chose not to participate. The remaining 276 individuals received a complete ophthalmological evaluation that was normal in 205 (74.3%) and showed salt and pepper retinopathy in 55 (19.9%) and other ocular abnormalities in 16 (5.8%). A comprehensive medical history, and a detailed physical examination were performed in the 205 children with normal ocular exam. Of these, 93 were found to have acquired deafness and/or associated anomalies and 112 (15.3% of the initial 731 children), non-syndromic deafness. The GJB2 gene was sequenced in these 112 individuals. RESULTS: Based on family history, 59.8% (67/112) of these cases had autosomal recessive non-syndromic sensorineural hearing loss and the remaining 40.2% (45/112) were sporadic, without apparent known cause. We identified three mutations in the GJB2 gene: 35delG, S199F, and 167delT, all of which have been previously reported in the literature, the variant M34T, and the polymorphism V27I. S199F was the most frequent mutation (17.9%), followed by 35delG (17.0%) and 167delT (0.4%). The mutations in the GJB2 gene were present in 50.7% of the autosomal recessive group and in 33.3% of the sporadic cases. CONCLUSIONS: Our pilot study showed that 15.3% of institutionalized deaf children in Bogotá have non-syndromic deafness and among them, the frequency of the S199F mutation was higher than reported in previous studies, whereas the frequency of the 35delG is similar to Caucasian populations. The fact that the S199F mutation was the most frequent allele in our study confirms the fact that the prevalence of GJB2 mutations depends on the ethnic origin. We emphasize the need to follow a strict protocol to identify bona fide cases of non-syndromic deafness among individuals with congenital hearing loss in order to identify the molecular basis of this condition.

Genetic counseling in Usher syndrome: linkage and mutational analysis of 10 Colombian families.

Usher Syndrome (US), an autosomal recessive disease, is characterized by retinitis pigmentosa (RP), vestibular dysfunction, and congenital sensorineural deafness. There are three recognized clinical types of the disorder. In order to improve genetic counseling for affected families, we conducted linkage analysis and DNA sequencing in 10 Colombian families with confirmed diagnosis of US (4 type I and 6 type II). Seventy-five percent of the US1 families showed linkage to locus USH1B, while the remaining 25% showed linkage to loci USH1B and USH1C. Among families showing linkage to USH1B we found two different mutations in the MYO7A gene: IVS42-26insTTGAG in exon 43 (heterozygous state) and R634X (CGA-TGA) in exon 16 (homozygous state). All six US2 families showed linkage to locus USH2A. Of them, 4 had c.2299delG mutation (1 homozygote state and 3 heterozygous); in the remaining 2 we did not identify any pathologic DNA variant. USH2A individuals with a 2299delG mutation presented a typical and homogeneous retinal phenotype with bilateral severe hearing loss, except for one individual with a heterozygous 2299delG mutation, whose hearing loss was asymmetric, but more profound than in the other cases. The study of these families adds to the genotype-phenotype characterization of the different types and subtypes of US and facilitates genetic counseling in these families. We would like to emphasize the need to perform DNA studies as a prerequisite for genetic counseling in affected families.

Effect of protein restriction diet on renal function and metabolic control in patients with type 2 diabetes: a randomized clinical trial.

OBJECTIVE: To assess the effect of a low protein diet (LPD) on renal function and metabolic control in three sub-groups of patients with type 2 diabetes those with or without nephropathy. RESEARCH DESIGN AND METHODS: A randomized clinical trial was conducted on 60 patients with type 2 diabetes in primary care -19 with normoalbuminuria, 22 with microalbuminuria, and 19 with macroalbuminuria-. All patients experienced a screening phase during the 3 months, and were designated according to percentages of daily caloric intake (e.g., carbohydrates 50%, fat 30%, and 20% of protein). After this period, they were randomly assigned to receive either LPD (0.6-0.8 g/kg per day) or normal protein diet (NPD) (1.0-1.2 g/kg per day) for a period of 4 months. Twenty nine patients received LPD and 31 received NPD. Primary endpoints included measures of renal function (UAER, serum creatinine and GFR) and glycemic control (fasting glucose and glycosylated hemoglobin A1c). RESULTS: Renal function improved among patients with macroalbuminuria who received LPD: UAER decreased (1,280.7 +/- 1,139.7 to 444.4 +/- 329.8 mg/24 h; p < 0.05) and GFR increased (56.3 +/- 29.0-74.2 +/- 40.4 ml/min; p < 0.05). In normoalbuminuric and microalbuminuric patients, there were no significant changes in UAER or GFR after either diet. HbA1c decreased significantly among microalbuminuric patients on both diets (LPD, 8.2 +/- 1.6-7.2 +/- 1.8%; p < 0.05; NPD, 8.8 +/- 1.9-7.1 +/- 0.8%; p < 0.05) and among macroalbuminuric patients who received NPD (8.1 +/- 1.8-6.9 +/- 1.6%; p < 0.05). CONCLUSIONS: A moderated protein restriction diet improved the renal function in patients with type diabetes 2 and macroalbuminuria.

Deafness on the island of Providencia - Colombia: different etiology, different genetic counseling.

Providencia is a small island located in the Caribbean Ocean, northwest of Colombia with an unusually high frequency of individuals with hearing loss (5 in 1,000) is present. The hearing loss in the island was characterized as non-syndromic autosomal recessive deafness accounting for 47% (8/17) of the deaf population, Waardenburg Syndrome (deafness associated with pigmentary anomalies) for 29% (5/17), and the remaining 24% (4/17) are cases of sporadic non-syndromic deafness. For appropriate genetic counseling a complete pedigree of families with deaf individuals was constructed. The 35delG mutation in GJB2 gene, which encodes connexin 26 (Cx26), is responsible for the deafness observed in the 8 individuals with autosomal recessive non-syndromic hearing loss. The deaf individuals with Waardenburg Syndrome and the sporadic cases did not have this mutation. Therefore, we present here an atypical case of an isolated community with at least two different genetic etiologies for deafness: non-syndromic genetic deafness caused by the 35delG mutation in the GJB2 gene and deafness associated with Waardenburg Syndrome not related to GJB2. In a small and isolated population, it is feasible to assume that the deafness is caused by the same factor; however, Providencia is an atypical case. Therefore, it is extremely important to define the exact etiology of deafness in each case, since different etiologies require different genetic counseling.

[Patient satisfaction with the process of computerisation, consent and decision making during hospitalisation]. / Satisfacción de los pacientes con el proceso de información, consentimiento y toma de decisiones durante la hospitalización.

UNLABELLED: The health organisations have moved from being centred on the professionals and are now centred on users and their expectations. The new health institutions want to know patients' perception of the quality of the care received, with particular respect to the information received, consent and decision making. It is necessary to have available measuring instruments that explore the different components of the process of information, consent and decision making. BACKGROUND: To identify the dimensions related to the process of information, consent and decision making of most importance to patients and susceptible to evaluation by questionnaire. SUBJECTS AND METHODS: Adult persons who have been hospitalised for at least two days. Qualitative study using semi-structured interviews. RESULTS: The participants wish to be informed and to participate in decision making; they do not know the meaning of the charter of patients' rights; they wish to share the whole care process with their family; written information is incomprehensible to them; and they feel that their pain and discomfort do not receive appropriate attention. CONCLUSION: It would be convenient to include the following dimensions in the questionnaires on satisfaction: a) the possibility of clarifying doubts; b) real knowledge of the rights and duties of patients; c) participation by the family in the care process; d) continuity of the same informer throughout hospitalisation; d) degree of understanding of the written information; e) involvement in decision making; and f) attention to pain and discomfort.

Head posture and dental wear evaluation of bruxist children with primary teeth.

UNLABELLED: The aim of the present study was to compare the head position and dental wear of bruxist and non-bruxist children with primary dentition. METHODS: All the subjects had complete primary dentition, dental and skeletal class I occlusion and were classified as bruxist or non-bruxist according to their anxiety level, bruxism described by their parents and signs of temporomandibular disorders. The dental wear was drawn in dental casts and processed in digital format. Physiotherapeutic evaluation and a cephalometric radiograph with natural head position were also performed for each child to evaluate the cranio-cervical position for the bruxist group (n = 33) and the control group (n = 20). The variables of the two groups were compared, using the Student t-test and Mann-Whitney U-test. RESULTS: A more anterior and downward head tilt was found in the bruxist group, with statistically significant differences compared with the controls. More significant dental wear was observed in the bruxist children. CONCLUSIONS: Bruxism seems to be related to altered natural head posture and more intense dental wear. Further studies are necessary to explore bruxism mechanisms.

Association of visceral fat with coronary risk factors in a population-based sample of postmenopausal women.

OBJECTIVE: To investigate in a population-based random sample of postmenopausal women the adjusted association of visceral adipose tissue (VAT) with coronary risk factors. DESIGN: Cross-sectional population-based random sample study. SUBJECTS: Ninety-eight postmenopausal women (age 50-65 y). MEASUREMENTS: Visceral and subcutaneous fat areas by computer axial tomography, anthropometry, lipid profile, fasting glucose and insulin, diet, physical activity, smoking status and alcohol intake. RESULTS: Compared to women with low VAT, women with high VAT (>117.8 cm(2)) had a less favorable metabolic profile with significantly higher fasting glucose (120+/-50 vs 98+/-39), insulin (7.9+/-10 vs 5+/-8), triglycerides (172+/-69 vs 127+/-72), apolipoprotein B (119+/-24 vs 98+/-32) and significantly lower HDL-C (38+/-10 vs 46+/-14) values in the whole sample (n=98). A similar profile was found in women without diabetes and hypertension (n=39). In multiple regression models, VAT explained a portion of the variance of TG (6.2%) in the entire sample and of total cholesterol (12.4%), LDL-C (15.8%), triglycerides (16.3%), apolipoprotein B (11.6%), and fasting glucose (28.4%) in the group of non-diabetic or hypertensive women. Our VAT cut-off point of 117.8 cm(2) corresponded to a waist circumference of 84 cm. CONCLUSION: Our results in a random population-based sample of postmenopausal women confirm the association of VAT with most coronary risk factors. These associations persisted after adjusting for diet, physical activity, smoking status and alcohol intake.

Hemangiopericitoma infantil / Infantile Hemangiopericytoma

Los hemangiopericitomas son tumores poco comunes, originados en un tipo de células mesenquimales que rodean a los vasos sanguíneos llamadas pericitos. Estos tumores constituyen apenas el 1 por ciento de las neoplasias vasculares en la población general, siendo aún más raros en los niños. Se presenta el caso de un recién nacido con diagnóstico confirmado histológicamente de hemangiopericitoma infantil, se discuten los hallazgos imaginológicos y los diagnósticos diferenciales

Enanismo hipofisiario idiopatico: Imagen por resonancia magnetica / Idiopathic pituitary dwarfism: Magnetic resonance imaging

El enanismo hipofisiario idiopático constituye una patología de presentación esporádica cuya causa a pesar del asocio con trauma de parto y malformaciones nerviosas de línea media, permanece desconocida. Puede presentarse con déficit aislado de hormona de crecimiento o asociado a múltiples déficits hormonales hipofisiarios. La introducción de la imagen por resonancia magnética (RM) para el estudio de la hipófisis ha permitido detectar una serie de hallazgos característicos de esta patología y a los cuales se les atribuye valor pronóstico. Estos son: La ausencia o hipoplasia del infundíbulo hipofisiario y / o la hipófisis anterior y la neurohipófisis ectópica

Novel infectious bronchitis virus S1 genotypes in Mexico 1998-1999.

Seventeen infectious bronchitis virus (IBV) field isolates recovered from commercial broiler flocks in Mexico were identified by reverse transcription-polymerase chain reaction cycle sequencing of the S1 gene. The isolates were obtained from broilers on farms from the neighboring states of Queretaro and San Luis Potosi in 1998 and 1999. Flocks had an ongoing history of bacterial-complicated respiratory disease with mortality rates as high as 28% in spite of receiving live vaccinations for Massachusetts and Connecticut strains of IBV. Sequence analysis of the S1 gene identified two unique genotypes that have been described, as of this time, only in Mexico and thus appear to represent strains indigenous to the country. The Mex/1765/99 genotype was isolated from 64% (11/17) of the respiratory disease outbreaks. Three isolates (18%) were similar to the BL-56 genotype, a unique Mexican IBV strain observed initially in 1996. In addition to the two indigenous strains, three isolates (18%) were found to be the Connecticut genotype.

Evaluacion de la anatomia arterial en donantes renales intrafamiliares: comparacion de angiografia por tomografia computada helicoidal y angiografia convencional / HCTA and conventional angiography for the evaluation of arterial anatomy in intrafamiliar renal donors

El propósito de este estudio es comparar los hallazgos de angiografía por tomografía computada helicoidal (TCH) con los de angiografía convencional y los hallazgos quirúrgicos en un grupo de donantes renales en el Hospital Universitario San Vicente de Paúl entre junio de 1996 y abril de 1998. Se realizó angiografía por TCH en 41 potenciales donantes renales quienes fueron remitidos al departamento de imágenes diagnósticas del H.U.S.V.R para evaluación con angiografía convencional. Para la angiografía por TCH, se inyectaron 100 ce de contraste intravenoso (iopamidol 300 mg/ml) y se hicieron reconstrucciones tridimensionales del árbol arterial. Los estudios de angiografía por TCH fueron evaluados por dos radiólogos en forma independiente; las diferencias de interpretación entre los observadores se resolvieron por consenso de ambos. Se compararon los hallazgos de ambas las entre sí y con los datos quirúrgicos en las unidades renales transplantadas. Utilizando la angiografía convencional como prueba de oro, la sensibilidad de la angiografía por TCH para la detección de variantes anatómicas arteriales fue del 100 por ciento y la especificidad del 97 por ciento , con una concordancia del 98 por ciento . Además, se demostraron anormalidades parenquimatosas y extrarenales, no visualizadas en la angiografía convencional. Los resultados permiten proponer el reemplazo de la angiografía convencional por la angiografía por TCH en la valoración de este tipo de pacientes, la cual se constituye en una herramienta rápida, segura, no invasora y menos costosa en nuestro medio. El uso de una menor cantidad de medio de contraste, con relación a los reportes ya publicados, podría contribuir a disminuir la nefrotoxicidad lo cual es deseable tanto en el donante como en el receptor

Sinusitis e insuficiencia renal / Sinusitis and renal insufficiency

Hombre de 27 años, nacido en Medellín. Comerciante, soltero y sin hijos. Hospitalizado por Otorrinolaringología con diagnostico de sinusitis bacteriana recurrente. Además dentro de los estudios diagnósticos se encontraron infiltrados pulmonares nodulares bilaterales.

Intoxicacion por plomo / Lead poisoning

Se presenta el caso de una niña hospitalizada por una bronconeumonía, con necesidad de ventilación mecánica. Además con retardo en el desarrollo psicomotor, alteración en su estado de conciencia y ribete de Burton en encías. Con estudios radiológicos que mostraron bandas radiopacas metafisarias en huesos largos e hiperdensidad en ganglios básales. Se encontraron niveles séricos de plomo elevados

A Colombian family with X-linked juvenile retinoschisis with three affected females finding of a frameshift mutation.

X-linked retinoschisis (XLRS) is a vitreoretinal disease responsible for most cases of juvenile macular degeneration in males. Retinoschisis carrier females generally manifest no pathological symptoms. However, a large affected family from Colombia presented three affected females with typical RS phenotype similar to their 27 affected male relatives. Fundus examination as well as electroretinograms (ERG) indicate that the disease in these three affected females is as severe as in their affected male counterparts. DNA sequence analysis of the XLRS1 gene in the affected members of this family indicates a single base (G) deletion at the 639 base position (639delG). This deletion causes a frameshift during translation and results in a larger (235 amino acids) than normal peptide (224 amino acids) with grossly altered discoidin domain, which is considered critical for the cellular function of the protein. The co-segregation of this gene mutation with the RS phenotype and the RS carrier status as well as its complete absence in normal controls indicates that this genetic change is responsible for the RS pathology in this family. This (639delG) is a novel RS mutation and reported here for the first time. Furthermore, the analysis of the three affected females indicates that the RS pathology in affected females (a very rare occurrence) is due to XLRS1 mutations carried on both of their X chromosomes.

Dissemination of a chloramphenicol- and tetracycline-resistant but penicillin-susceptible invasive clone of serotype 5 Streptococcus pneumoniae in Colombia.

A national surveillance conducted in Colombia between 1994 and 1996 identified serotype 5 Streptococcus pneumoniae as the second most frequent cause of invasive disease in children younger than 5 years of age. All 43 serotype 5 isolates collected during this period were shown to be susceptible to penicillin, erythromycin, cefotaxime, and vancomycin, but most (38 of 43, or 88%) were highly resistant to chloramphenicol. In order to clarify a possible genetic relatedness among these isolates, additional microbiological and molecular characterizations were performed. Most (40 of 43, or 93%) of the isolates were found to be resistant to tetracycline. Pulsed-field gel electrophoresis (PFGE) patterns of chromosomal DNAs revealed that all the 43 isolates were closely related and that 38 of the 43 isolates were representatives of a "Colombian clone" of S. pneumoniae isolates which were recovered throughout the 3-year surveillance period from patients in 13 hospitals located in five Colombian cities. Isolates belonging to this Colombian clone were resistant to chloramphenicol and tetracycline, hybridized with the cat and tetM DNA probes in the same 340-kb SmaI fragment, and had identical PFGE patterns after both SmaI and ApaI digestions.