Organochlorine residues in South American sea lions, Otaria flavescens (Shaw, 1800): bioaccumulation and time trends.

Blubber from stranded South American sea lions (Otaria flavescens) was sampled between 1991 and 2005 on the Peninsula Valdés in Argentina and analyzed for organochlorine (OC) pollutants. Mean blubber concentrations, expressed on an extractable basis, were 686 (SD = 1,060) ng g(-1) for dichlorodiphenyl trichloroethane (tDDT) and 735 (SD = 787) ng g(-1) for polychlorinated byphenils (PCB). The OC levels were well below those associated with adverse sublethal effects and lethality in mammals. OC concentrations showed statistically significant associations with age that were positive in males and negative in females. These trends are consistent with the majority of marine mammal populations studied. There were no trends in the levels of tDDT or PCB over time. In spite of the low levels detected, OC contamination was present consistently over the 14-year period, suggesting continuous inputs from geographic redistribution.

Health care-related infections in solid organ transplants

The health care-related infections are well-known in a critical care setting, but reports of those infections in solid organ transplanted patients are scarce. We developed a study of retrospective cohort in a tertiary teaching hospital for 14 months. Eighty-one patients underwent solid organ transplants. The global incidence of health care-related infection was 42.0 percent. Fifteen percent of the cases were occurrences of surgical site infections, 14.0 percent pneumonias, 9.0 percent primary blood stream infections, 4.0 percent urinary tract infections and 2.0 percent skin infection. The most prevalent etiologic agents were K. pneumoniae (8.6 percent), P. aeruginosa (7.4 percent); A. baumannii (5.0 percent) and S. aureus (2.5 percent). Mortality was 18.0 percent, none of then related to health care infections. The high rate of those infections, mainly surgical site infections, suggests a demand for stricter measures to prevent and control health care-related infections.

[Retinopathy of prematurity in the XXI century in a developing country: an emergency that should be resolved]. / La retinopatía del prematuro en el siglo XXI en un país en desarrollo: una urgencia que debe ser resuelta.

INTRODUCTION: Retinopathy of prematurity (ROP) is the first cause of childhood blindness in Argentina and is reaching epidemic proportions. To gain greater insight into the issues involved in this epidemic, we analyzed the characteristics of the infants referred for treatment of very severe ROP to the Dr. Juan P. Garrahan Pediatric Hospital, located in the city of Buenos Aires. METHODS: We performed a retrospective study of patients referred for ROP from 01/01/96 to 12/31/03. Very severe ROP was defined as threshold disease or worse in both eyes, plus disease in zones 1 or 2, or Rush disease. Unusual patients were defined as those with very severe ROP with a gestational age (GA) of > 31 weeks or birth weight (BW) > 1500 g. Patients were divided into two groups according to the distance between the referring center and our hospital: group A consisted of those from nearby areas ( 70 km from the hospital. RESULTS: During the study period, the number of cases progressively increased while the proportion of "unusual" patients slightly decreased. The total number of infants referred was 809 and 14 % were unusual patients; 55 % had very severe ROP, 89 % were treated, and 7 % were referred too late and lost the opportunity for treatment. Group B comprised 61 % of the infants referred. Very severe ROP was present in 53 % of patients in group A and in 56 % of those in group B. The mean GA was 29.5 +/- 3.1 weeks in group A and 30.8 +/- 2.6 in group B (p < 0.001); 90.5 % of the patients in group A and 64 % of those in group B required mechanical ventilation (p < 0.001). No predictors for very severe ROP were found in multifactorial analysis. CONCLUSIONS: We report a childhood epidemic of blindness in which the prevalence of very severe ROP increased during the study period and the disease occurred in large, fairly mature newborns. The differences found in relation to the referring center and the lack of correlation between very severe ROP and prematurity or the use of mechanical ventilation suggests substantial disparity in healthcare, which should be taken into account when planning prevention strategies.

Phase II trial: concurrent radio-chemotherapy with weekly docetaxel for advanced squamous cell carcinoma of head and neck.

INTRODUCTION: Standard fractionation radiation therapy (RT) combined with concomitant chemotherapy (CT) based on cisplatin schemes is actually the standard treatment for locally advanced non-resectable squamous cell carcinoma of head and neck (SCCHN). The appearance of taxoids has introduced a new kind of treatment with high antitumoral power. The aim of this study is to add more information about the role of this new approach. MATERIALS AND METHODS: Twenty-six patients with locally advanced non-resectable SCCHN were recruited at six institutions in Spain, between January 2001 and January 2003. Docetaxel was administered weekly, for 6 weeks, concurrently with RT. RESULTS: The mean total delivered dose of RT was 70'2 Gy (range 64-74 Gy). The median and mean duration of time were 63 days and 61 days (range 49-103 days) respectively. After a median time control of 19 months (range 3.3-42.2 months), the response rate was 83.4%. The median time to local progression was 16.4 months (95% confidence interval [CI]=4.4-28.4 months). The median survival time was 26.9 months, with one- and two-year overall survival of 66.9% (95% CI=48.1-85.7%) and 57.5% (95% CI=37.3-77.7%) respectively. The median duration time response was 15.1 months (95% CI=3.7-26.5 months). The median time until treatment failure was 9.4 months (95% CI=4.7-14.1). Incidence of grade III-IV mucositis was 88%, neutropenia 72% and skin toxicity 92% (24% grade III-IV). The incidence of severe late toxicity (grade III and IV) due to RT/CT was 31.4%. CONCLUSIONS: Although therapeutics results are equivalent to cisplatin schemes of concurrent CT-RT, mucositis and cutaneous toxicity registered in this trial must be considered as limiting factors to application of this new approach.

Health care-related infections in solid organ transplants.

The health care-related infections are well-known in a critical care setting, but reports of those infections in solid organ transplanted patients are scarce. We developed a study of retrospective cohort in a tertiary teaching hospital for 14 months. Eighty-one patients underwent solid organ transplants. The global incidence of health care-related infection was 42.0%. Fifteen percent of the cases were occurrences of surgical site infections, 14.0% pneumonias, 9.0% primary blood stream infections, 4.0% urinary tract infections and 2.0% skin infection. The most prevalent etiologic agents were K. pneumoniae (8.6%), P. aeruginosa (7.4%); A. baumannii (5.0%) and S. aureus (2.5%). Mortality was 18.0%, none of then related to health care infections. The high rate of those infections, mainly surgical site infections, suggests a demand for stricter measures to prevent and control health care-related infections.

Phase III randomized pilot study comparing interferon alpha-2b in combination with radiation therapy versus radiation therapy alone in patients with stage III-B carcinoma of the cervix.

This randomized pilot study was designed to determine whether the addition of interferon alpha-2b to standard radiation therapy offered an advantage in loco-regional control and survival over radiation therapy alone in a homogeneous group of patients with stage IIIB carcinoma of the cervix. Thirty-six patients were treated with a combination of interferon alpha-2b plus radiation therapy, and 38 patients were treated with radiation therapy alone. Patients with evidence of ureteral obstruction were excluded from the study. Evaluation of loco-regional response was determined by pelvic examination, cervical cytology, biopsies and CT scans when indicated. Survival time was measured from initiation of treatment to date of death or last follow-up. Patient characteristics were comparable between both study arms. The objective complete response rate was 67% in the combined therapy group and 55% in the radiation alone group (P = 0.454). With a median follow-up of 17 months for all patients and 31 months for live patients, 50% of the combined group survived vs. 39.5% of the radiation alone group (P = 0.424). We conclude that the addition of interferon alpha-2b to standard radiation therapy did not significantly improve loco-regional response or survival, although such a trend was noted. We encourage the design of a larger randomized study with sufficient power to detect meaningful differences to prove whether the tendency observed in the present investigation holds any promise to improve the outcome of these patients.

Ventilación mecánica en el recién nacido de muy bajo peso al nacer / Respiration artificial in the infant very low birth weight

Este artículo podrá servir de guía para uno de los desafíos más importantes de la neonatología intensivaLa ventilación es sólo una parte de su manejo integral y complejo, pero de ser mal utilizada se asocia con mortalidad innecesaria o con morbilidad que puede durar el resto de la vida

Asociación entre el fenotipo fisura labiopalatina no sindrómica y marcadores de microsatélites ubicados en 6p, 17q y 19q / Association study of the nonsyndromic cleft lip/palate phenotype and microsatellite markers located in 6p, 17q and 19q

Background: In the search of the major genes responsible for the genetic etiology of Nonsyndromic Cleft Lip and Palate (NSCLP), an association study between this malformation and four molecular markers, F13A1 and EDN1 (6p), D17S579 (17q) and BCL3 (19q), was done. Aim: To determine, in a Chilean population, the presence of NSCLP susceptibility regions, as proposed for Caucasian populations in the 6p, 17q and 19q chromosomal regions. Material and Methods: A sample of unrelated NSCLP patients, that belonged to Simplex (Sx) and Multiplex (Mx) families, was analyzed. Blood donors were used as a control group (Co). The DNA of the four markers was amplified by means of PCR, their products analyzed by PAGE denaturants and visualized by silver staining. Statistical analysis was performed using c2 log ratio. Results: Allele frequency distribution of D17S579 was significantly different in all patients with NSCLP and their subgroups, when compared to control subjects. Significant differences in EDN1 frecuency were observed between the total groups of NSCLP patients and those pertaining to the Mx subgroup, when compared to controls. Differences in F13A1 distribution were only observed between NSCLP-Mx patients and controls. There was a slight difference in BCL3 distribution, between the total sample of NSCLP patients and controls. Conclusions: Our results support the hypothesis of the existence of cleft susceptibility regions in 6p and 17q. The small significance of BCL3, suggests that ethnicity can influence the interactions between involved genes

Asociación entre el fenotipo fisura labiopalatina no sindrómica y marcadores de microsatélite ubicados en 4q / Association between nonsyndromic cleft lip/palate with microsatellite markers located in 4q

Background: Nonsyndromic cleft lip with or without cleft palate (NSCLP) is a common craniofacial defect. Association studies have suggested that a cleftinglocus is located on chromosome 4q at or near two microsatellite markers D4S175 and D4S192. Aim: To test the hypothesis on the possible presence of a clefting locus on chromosome 4q. Material and methods: We carried out an association study on a sample of unrelated NSCLP patients, of their unaffected relatives and in controls. Both probands and relatives were further analyzed depending if they originated from simplex or multiplex families. DNA was analyzed with two PCR markers close to the putative NSCLP locus, dinucleotide repeats D4S175 and D4S192. PCR products were resolved by PAGE and visualized by silver staining. Statistical analysis was performed by means of c2 log ratio. Results: Significant differences between NSCLP and controls were observed when comparing the allele frequency distribution of D4S192 both in the total sample as well as in NSCLP-multiplex and simplex cases. No significant differences for D4S175 were observed in any of the comparisons. Unaffected relatives showed significant differences with controls both for D4S175 and D4S192. Conclusions: Our results support the hypothesis that a NSCLP locus maps on chromosome 4q close to the microsatellite marker D4S192. No differences were observed between NSCLP multiplex and simplex cases versus controls, implying that they do not represent different etiologic entities. The results of the present and previous studies in the same group of patients support the hypothesis that several major interacting genes participate in the etiology of NSCLP

Randomized multicenter trial comparing synchronized and conventional intermittent mandatory ventilation in neonates.

OBJECTIVE: To compare synchronized intermittent mandatory ventilation (SIMV) and conventional intermittent mandatory ventilation (IMV) in neonates. STUDY DESIGN: Prospective, multicenter, randomized clinical trial. SETTING: Level III neonatal intensive care units at six university or children's hospitals. PATIENTS: Three hundred twenty-seven infants receiving conventional IMV for respiratory distress syndrome, pneumonia, or meconium aspiration pneumonitis were randomly assigned a 7.5 +/- 6 hours of age to either continue with IMV or change to SIMV. Infants assigned to each mode of ventilation had similar birth weight (BW), gestational age, and Apgar scores at birth, and similar oxygenation indexes at randomization. They received similar surfactant therapy and had similar incidence of sepsis, seizures, secondary pneumonia, and necrotizing enterocolitis. In the infants with BW less than 1000 gm, more infants receiving IMV had surgical ligation of their patent ductus arteriosus than did those receiving SIMV (27 vs. 7 %; p = 0.02). ANALYSIS: Data was analyzed overall for all infants and also separately within three BW groups: less than 1000 gm, 1000 to 2000 gm, and more than 2000 gm. The 1000 to 2000 gm BW group was further analyzed in subgroups weighing 1000 to 1499 gm and 1500 to 2000 gm. RESULTS: In all infants, at 1 hour after randomization, the infants receiving SIMV had a lower mean airway pressure than those receiving IMV (8.08 +/- 2.15 vs. 8.63 +/- 2.59; p<0.05), with similar fractions of inspired oxygen and oxygenation indexes. Infants whose BW was 1000 to 2000 gm at 0.5 hour required a lower fraction of inspired oxygen with SIMV than with IMV (0.52 +/- 0.20 vs. 0.62 +/- 0.27; p<0.05) and had better oxygenation at 1 hour, as shown by lower oxygenation indexes with SIMV than with IMV (6.14 +/- 4.17 vs. 9.42 +/- 8.41; p = 0.01). Infants whose BW was 1000 to 2000 gm received a lower number of unit doses of sedative/analgesic drugs per infant during the first 4 days of SIMV than did infants receiving IMV (3.8 +/- 3.4 vs 6.3 +/- 5.5 unit doses; p = 0.02). Infants whose BW was more than 2000 gm had a shorter duration of mechanical ventilation with SIMV than with IMV (median, 72 vs 93 hours; p = 0.02). Three of the forty-six infants receiving IMV but none of the 47 infants receiving SIMV required extracorporeal membrane oxygenation. In the infants with BW less than 1000 gm, fewer infants treated with SIMV required supplemental oxygen at 36 weeks of postconceptional age than did those treated with IMV (47 vs 72%; p<0.05). In 83 infants whose lungs were mechanically ventilated for 14 days or longer, all with BW less than 2000 gm, those treated with SIMV regained their BW earlier than those treated with IMV (median, 21.5 vs 29 days; p<0.01). There were no differences in the rates of death, intraventricular hemorrhage (grades III and IV), air leak, need for pharmacologic paralysis, or need for supplemental oxygen at 28 days. CONCLUSIONS: We found that SIMV was at least as efficacious as conventional IMV, and may have improved certain outcomes in BW-specific groups.

Treatment of peripheral tissue ischemia with topical nitroglycerin ointment in neonates.

Four neonates had resolution of peripheral tissue ischemia after the application of 2% nitroglycerin ointment. A dosage of 4 mm nitroglycerin ointment per kilogram of body weight was applied to two patients with ischemia caused by vasospasm from indwelling radial artery catheterization and to two patients with ischemia resulting from dopamine extravasation. No adverse effects were noted except mild episodes of decreased blood pressure in two of the patients.

Neonatal polycythemia in appropriately grown infants of hypertensive mothers.

Neonatal polycythemia is a frequent finding after pregnancies complicated by diabetes and by maternal hypertension with intrauterine growth retardation (IUGR). It is still unclear if the association of polycythemia with hypertension is the result of IUGR or of hypertension per se. To establish the incidence of neonatal polycythemia in populations at risk, we analyzed the results of hematocrit values obtained from 1592 neonates born consecutively at the Hospital de Clinicas, Buenos Aires. Capillary hematocrit values were obtained by heel stick before 6 h of age. When the values were 65% or greater, new samples were obtained from an antecubital vein. The risk of polycythemia in appropriately grown infants of hypertensive mothers was 12.6-fold greater than the risk in the general population. These data show that maternal hypertension poses a significant risk for polycythemia, regardless of fetal growth. We suggest that, to prevent possible sequela, hematocrit is measured routinely in all infants of hypertensive mothers for prompt diagnosis and treatment.

Lack of relationship between the true airway pressure and the pressure displayed with an infant ventilator.

OBJECTIVE: To establish if the pressure indicated in the manometer of an infant ventilator (IV 100B, Sechrist, Anaheim, CA) reflects the true pressure delivered to the proximal airway during mechanical ventilation in the neonatal ICU. DESIGN: With approval of our Institutional Research Board, data were collected prospectively. Peak inspiratory pressure and end-expiratory pressure were measured at the "Y" piece of the breathing tubing. Pressure readings from the conventional ventilator's manometer were compared with simultaneously obtained measurements using an electronic monitor. SETTING: This study was conducted in a 45-bed neonatal ICU, admitting 700 to 750 newborns per year. PATIENTS: Twelve neonates who required mechanical ventilation were included in the study. INTERVENTIONS: Specific interventions were not made by study design. Measurements routinely obtained were compared. MEASUREMENTS AND MAIN RESULTS: Two hundred seventy-five simultaneous measurements of peak inspiratory pressure and positive end-expiratory pressure were compared. Peak inspiratory pressure values were higher with the electronic monitor in 273 (99%) of 275 measurements and the mean of the differences between the electronic monitor and ventilator's manometer was statistically significant (p less than .001). For positive end-expiratory pressure measurements, values indicated by the electronic monitor were lower in 152 (55%) of 275 determinations, equal in 65 (23%), and higher in 58 (21%) determinations. Percent variations between methods ranged from 0% to 140% for peak inspiratory pressures and from 0% to 500% for positive end-expiratory pressure. CONCLUSIONS: These data demonstrate that it is impossible to know the true pressure delivered to the proximal airway of a neonate during mechanical ventilation by observing the ventilator pressure manometer. The manometer readings consistently underestimate the true peak inspiratory pressure values and are very unpredictable regarding positive end-expiratory pressure values. These findings support the use of other methods to monitor the proximal airway pressure besides the ventilator's manometer in the neonatal ICU. Furthermore, mean airway pressure should not be calculated from the pressure readings obtained from the tested ventilator's manometer.

Resultados de la cirugía conservadora en el carcinoma invasor de mama precoz / Results of the conservative surgery in the early breast invasive carcinoma

Se analizan los resultados de la cirugía conservadora sin vaciamiento axilar, seguida de radioterapia y la sobrevida en 127 pacientes con cáncer de mama en estadio T1 - T2 No Mo a 144 meses. La población en estudio está constituida por 59 pacientes (46,4%) en T1 y 68 (53,5%) en T2. La edad promedio fue de 53 años para T1 y de 56 años para T2. El 83,2% de las pacientes en T1 tiene una SSEE a 120 meses. La mediana de seguimiento es de 54 meses. La sobrevida total actuarial es de 89,9%. El 11,8% (7/59) fracasaron. Tres (5%) en la zona locorregional y 4 (6,6%) a distancia. El 8% de los fracasos locorregionales lo hicieron en axila, mientras que en mama fue el 1,7%. Dos pacientes tienen fracaso en 2 o más localizaciones simultáneas. El 60,5% de las pacientes en T2 tienen una SSEE a 120 meses. La mediana de seguimiento es de 61 meses. La sobrevida total actuarial es de 77,7%. El 30% (21/68) fracasaron, 4 en la zona locorregional y 17 a distancia. Dos de los fracasos locorregionales fueron en axila y dos en la mama. Seis pacientes tienen dos o más fracasos simultáneos (locorregionales a distancia). Se concluye que en comparación a publicaciones con tratamientos similares, los resultados obtenidos son semejantes; pero al compararlos con los resultados obtenidos con técnicas conservadoras, en que se hace vaciamiento axilar, aquéllos son significativamente superiores, especialmente por los resultados obtenidos en axila