On the Preparation of Thin Films of Stearyl Methacrylate Directly Photo-polymerized at the Air-Water Interface

Characterization of bidimensional polymeric films at the air-water interface in the Langmuir trough, despite being a recurrent topic, usually refers to films of already formed polymeric materials, with very scarce reports on direct polymerization at the air-water interface. In the present work, we studied the photo-polymerization of stearyl methacrylate directly at the air-water interface under a nitrogen atmosphere, with the radical initiator solubilized in the aqueous phase. Two-dimensional (2D) polymerization was monitored by measuring the pressure-area isotherm at different irradiation times. The polymerization leads to a film with an isotherm different from that observed for the monomer, where the surface pressure is directly related to the irradiation time. The shape of this isotherm confirms the presence of a compressed liquid phase, where a higher order can be attained as a consequence of stronger packing forces involving polymer chains. The presence of inter-chain interactions allows rearrangements on the surface of the subphase, and even before the collapse a dense 2D ordering (with a solid phase-like behavior) can be observed. We present a new one-step, solvent-free procedure to obtain a photo-polymeric film directly at the air-water interface, which can be transferred to a solid surface by the Langmuir-Blodgett method, allowing film preparation of controlled thickness. Films were characterized by measuring properties such as thickness, roughness, and hydrophobicity and comparing them with films obtained from a conventional polymer. We report the differences between the interfacial behavior of amphiphilic molecules and nanomaterials such as films obtained by photo-polymerization, PSMA, directly on the air-water interface.

An RCT of Rapid Genomic Sequencing among Seriously Ill Infants Results in High Clinical Utility, Changes in Management, and Low Perceived Harm

The second Newborn Sequencing in Genomic Medicine and Public Health (NSIGHT2) study was a randomized, controlled trial of rapid whole-genome sequencing (rWGS) or rapid whole-exome sequencing (rWES) in infants with diseases of unknown etiology in intensive care units (ICUs). Gravely ill infants were not randomized and received ultra-rapid whole-genome sequencing (urWGS). Herein we report results of clinician surveys of the clinical utility of rapid genomic sequencing (RGS). The primary end-point-clinician perception that RGS was useful- was met for 154 (77%) of 201 infants. Both positive and negative tests were rated as having clinical utility (42 of 45 [93%] and 112 of 156 [72%], respectively). Physicians reported that RGS changed clinical management in 57 (28%) infants, particularly in those receiving urWGS (p = 0.0001) and positive tests (p < 0.00001). Outcomes of 32 (15%) infants were perceived to be changed by RGS. Positive tests changed outcomes more frequently than negative tests (p < 0.00001). In logistic regression models, the likelihood that RGS was perceived as useful increased 6.7-fold when associated with changes in management (95% CI 1.8-43.3). Changes in management were 10.1-fold more likely when results were positive (95% CI 4.7-22.4) and turnaround time was shorter (odds ratio 0.92, 95% CI 0.85-0.99). RGS seldom led to clinician-perceived confusion or distress among families (6 of 207 [3%]). In summary, clinicians perceived high clinical utility and low likelihood of harm with first-tier RGS of infants in ICUs with diseases of unknown etiology. RGS was perceived as beneficial irrespective of whether results were positive or negative.

Functional Precision Medicine Identifies New Therapeutic Candidates for Medulloblastoma

Medulloblastoma is among the most common malignant brain tumors in children. Recent studies have identified at least four subgroups of the disease that differ in terms of molecular characteristics and patient outcomes. Despite this heterogeneity, most patients with medulloblastoma receive similar therapies, including surgery, radiation, and intensive chemotherapy. Although these treatments prolong survival, many patients still die from the disease and survivors suffer severe long-term side effects from therapy. We hypothesize that each patient with medulloblastoma is sensitive to different therapies and that tailoring therapy based on the molecular and cellular characteristics of patients' tumors will improve outcomes. To test this, we assembled a panel of orthotopic patient-derived xenografts (PDX) and subjected them to DNA sequencing, gene expression profiling, and high-throughput drug screening. Analysis of DNA sequencing revealed that most medulloblastomas do not have actionable mutations that point to effective therapies. In contrast, gene expression and drug response data provided valuable information about potential therapies for every tumor. For example, drug screening demonstrated that actinomycin D, which is used for treatment of sarcoma but rarely for medulloblastoma, was active against PDXs representing Group 3 medulloblastoma, the most aggressive form of the disease. Functional analysis of tumor cells was successfully used in a clinical setting to identify more treatment options than sequencing alone. These studies suggest that it should be possible to move away from a one-size-fits-all approach and begin to treat each patient with therapies that are effective against their specific tumor. SIGNIFICANCE: These findings show that high-throughput drug screening identifies therapies for medulloblastoma that cannot be predicted by genomic or transcriptomic analysis.

A Randomized, Controlled Trial of the Analytic and Diagnostic Performance of Singleton and Trio, Rapid Genome and Exome Sequencing in Ill Infants

The second Newborn Sequencing in Genomic Medicine and Public Health study was a randomized, controlled trial of the effectiveness of rapid whole-genome or -exome sequencing (rWGS or rWES, respectively) in seriously ill infants with diseases of unknown etiology. Here we report comparisons of analytic and diagnostic performance. Of 1,248 ill inpatient infants, 578 (46%) had diseases of unknown etiology. 213 infants (37% of those eligible) were enrolled within 96 h of admission. 24 infants (11%) were very ill and received ultra-rapid whole-genome sequencing (urWGS). The remaining infants were randomized, 95 to rWES and 94 to rWGS. The analytic performance of rWGS was superior to rWES, including variants likely to affect protein function, and ClinVar pathogenic/likely pathogenic variants (p < 0.0001). The diagnostic performance of rWGS and rWES were similar (18 diagnoses in 94 infants [19%] versus 19 diagnoses in 95 infants [20%], respectively), as was time to result (median 11.0 versus 11.2 days, respectively). However, the proportion diagnosed by urWGS (11 of 24 [46%]) was higher than rWES/rWGS (p = 0.004) and time to result was less (median 4.6 days, p < 0.0001). The incremental diagnostic yield of reflexing to trio after negative proband analysis was 0.7% (1 of 147). In conclusion, rapid genomic sequencing can be performed as a first-tier diagnostic test in inpatient infants. urWGS had the shortest time to result, which was important in unstable infants, and those in whom a genetic diagnosis was likely to impact immediate management. Further comparison of urWGS and rWES is warranted because genomic technologies and knowledge of variant pathogenicity are evolving rapidly.

Building a network for multicenter, prospective research of central nervous system infections in South America: Process and lessons learned

Multicenter collaborative networks are essential for advancing research and improving clinical care for a variety of conditions. Research networks are particularly important for central nervous system infections, which remain difficult to study due to their sporadic occurrence and requirement for collection and testing of cerebrospinal fluid. Establishment of long-term research networks in resource-limited areas also facilitates diagnostic capacity building, surveillance for emerging pathogens, and provision of appropriate treatment where needed. We review our experience developing a research network for encephalitis among twelve hospitals in five Peruvian cities since 2009. We provide practical suggestions to aid other groups interested in advancing research on central nervous system infections in resource-limited areas.

An overview and impact assessment of OSHA large dairy local emphasis programs in New York and Wisconsin

BACKGROUND

Farming has been exempted from most labor regulations and shielded from regulatory scrutiny by the Occupational Safety and Health Administration (OSHA). Yet, agriculture and dairy in particular, has relatively high injury and fatality rates.

METHODS

A recent shift in OSHA's approach to agricultural worker safety and health includes two dairy-focused Local Emphasis Programs (LEPs), one launched in Wisconsin in 2011 and the other in New York in 2014. We examine data from LEP-related, OSHA consultations and inspections as well as non-governmental audit programs, and review farmer perceptions about the LEP.

RESULTS

Inspections conducted by OSHA and private consultation programs highlight the presence and variety of hazards on dairy farms in Wisconsin and New York.

CONCLUSION

The LEPs helped raise dairy producers' awareness of inherent hazards and methods to correct them. Farmers cited the LEP as beneficial, identifying it as a catalyst to reduce hazards on their farms.

The nasal microbiota of dairy farmers is more complex than oral microbiota, reflects occupational exposure, and provides competition for staphylococci

Allergic and autoimmune diseases had been attributed to lack of exposure to biodiversity, an important factor in regulating immune homeostasis in a healthy host. We posit that the microbiome of healthy dairy farmers (DF) will be richer than non-farmers (NF) living in urban settings due to exposure to a greater biodiversity in the dairy environment. However, no studies have investigated the relationships between microbiota of dairy farmers (DF) compared with urban non-farmers (NF). We compared the nasal and oral microbiota of dairy farmers (N_DF, O_DF, respectively) with nasal and oral microbiota of NF in the same geographical area. The N_DF showed high microbial diversity with hundreds of unique genera that reflected environmental/occupational exposures. The nasal and oral microbiomes clustered separately from each other using Principal Coordinate Analysis, and with DF harboring two-fold and 1.5-fold greater exclusive genera in their nose and mouth respectively, than did non-farmers. Additionally, the N_DF group had a lower burden of Staphylococcus spp. suggesting a correlation between higher microbial diversity and competition for colonization by staphylococci. The N_DF samples were negative for the mecA gene, a marker of methicillin-resistance in staphylococci. The lower burden of staphylococci was found to be independent of the abundance of Corynebacterium spp. Exposure to greater biodiversity could enhance microbial competition, thereby reducing colonization with opportunistic pathogens. Future studies will analyze whether exposure to livestock microbiomes offers protection from acute and chronic diseases.

Effect of gelatinized flour fraction on thermal and rheological properties of wheat-based dough and bread

This work considered gelatinized wheat flour fraction with properties similar to hydrocolloid to enhance the strength of dough network by improving water retention and rheological characteristics. The gelatinized (90 °C) fraction of the wheat flour was incorporated in the dough formulation at different levels (5, 10, and 20% w/w). The effects of the gelatinized flour (GF) fraction on the dough rheology and thermal properties were studied. The incorporation of GF induced a moderate increase of dough viscoelasticity and reduced the freezing and melting enthalpies. On the other hand, the changes in bread textural properties brought by incorporation of GF were insignificant, indicating that the gelatinized fraction acted as a binder that enhanced water trapping in the structure. SEM images showed a more heterogeneous crumb microstructure (e.g., gas cells, porous, etc.) bread prepared using GF. Drying kinetics obtained from TGA indicated that the water diffusivity decreased with the incorporation of GF, which suggested that the bread had a compact microstructure.

The use of audience response system technology with limited-english-proficiency, low-literacy, and vulnerable populations

Audience response systems (ARS) have long been used to improve the interactivity of educational activities. Most studies of ARS have addressed education of literate trainees. How well these devices work with low-literacy subjects is not well studied. Information gathering on the training audience is an important use of ARS and helpful in improving the targeting of training information. However, obtaining demographic information from vulnerable populations with reasons to be concerned about divulging information about themselves has not been tested. In addition, a culturally competent method to effectively collect demographic and evaluation data of this growing population is essential. This project investigated the use of ARS to gather information from Hispanic immigrant workers, many of whom are socially vulnerable and have limited English proficiency (LEP) and low-literacy. Workers attended focus groups and were asked to use ARS devices or clickers to respond to questions. Questions were both categorical (multiple choice) and open-ended numerical (text entry), and varied from simple queries to more sensitive points regarding immigration. Most workers answered the one-key response categorical questions with little difficulty. In contrast, some participants struggled when responding to numerical questions, especially when the response required pressing multiple clicker keys. An overwhelming majority of participants reported that the clickers were comfortable and easy to use despite the challenges presented by the more complex responses. The error rate increased as question complexity increased and the trend across three ordered categories of response complexity reached statistical significance. Results suggest that ARS is a viable method for gathering dichotomous or higher-order categorical information from LEP and low-literacy populations in a group setting while assuring anonymity. However, it is recommended that clickers be developed and tested with fewer, bigger, and more widely separated buttons, and less printing on the buttons for these populations. Further research is needed to determine the effectiveness of using clickers with simplified configurations in the workplace as a tool to collect data for surveys and assessments and to better engage LEP and low-literacy workers in training sessions.

Probiótico (enterococcus faecium) adicionado a dietas estándar y con baja proteína para cerdos

Se evaluó el comportamiento productivo (ganancia diaria de peso, GDP; consumo de alimento, COA; conversión alimenticia, CA; ganancia de carne magra, GCM), las características de la canal (área del músculo Longissimus, AML; grasa dorsal, GD; porcentaje de carne magra, CM), la concentración de urea en plasma, y la población microbiana en heces de 36 cerdos machos castrados híbridos (Yorkshire×Duroc×Pietrain) en iniciación (11,10 ± 0,51 kg), crecimiento (25,75 ± 1,13 kg), y finalización (51,03 ± 2,20 kg), en respuesta a dos niveles de proteína bruta (PB; iniciación: 20,5 y 16,0 %; crecimiento: 16,0 y 14,5 %; y finalización: 14,0 y 12,5 %) y dos niveles del probiótico (PRO) Enterococcus faecium (0,0 y 1,0 kg t-1 de alimento en cada etapa) en dietas sorgo-pasta de soya, en un diseño completamente al azar con arreglo factorial 2×2, con 9 repeticiones por tratamiento. La energía se mantuvo constante en 3,265 Mcal kg-1. En iniciación, la adición del PRO redujo (p£0,05) el AML, pero no afectó (p>0,05) otras variables en estudio; la urea en plasma disminuyó (p£0,05) en cerdos alimentados con baja proteína. En crecimiento y finalización, al reducir la PB disminuyó (p£0,01) la urea en plasma, pero no afectó (p>0,05) otras variables. Agregar PRO aumentó (p£0,05) la concentración de Enterococcus y el total de bacterias en heces en todas las etapas. Estos resultados indican que agregar PRO aumenta la población microbiana total y de Enterococcus, pero no afecta la respuesta productiva, las características de la canal, ni la concentración de urea en plasma de cerdos alimentados con dietas estándar o con baja proteína.

Using lignimerin (a recovered organic material from Kraft cellulose mill wastewater) as sorbent for Cu and Zn retention from aqueous solutions

Adsorption of copper and zinc in lignimerin (an organic material mainly composed by lignin, carbohydrate fragments and some extractives) and its acid derivative (H-lignimerin), recovered from Kraft cellulose mill wastewater was examined. A Box-Behnken experiment design, used to optimize lignimerin recovery process, revealed that the type of solvent used for precipitation is a determining factor in the amount of substance obtained. Conversely, batch adsorption studies at pH 4.0 revealed that the maximum adsorption capacities, modeled by the Langmuir equation, were 666.7 and 370.4 mmol kg(-1) for Cu(II) and Zn(II), respectively in lignimerin and 232.6 and 312.5 mmol kg(-1) for Cu(II) and Zn(II), respectively in H-lignimerin. The adsorption of Cu(II) and Zn(II) through deprotonated hydroxyl and carboxylic groups was the dominant mechanism that may explain the adsorption in both materials. The adsorption capacities indicated that lignimerin, with a molecular mass between 50 and 70 kDa, has a potential use as an organic sorbent for removing copper and zinc from liquid resources.

Effect of primary polychemotherapy after sentinel lymph node biopsy on the necessity for lymphadenectomy in stage II breast cancer patients

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Background: Sentinel lymph node (SLN) biopsy is the standard procedure for assessing axillary status in stage I-II breast cancer patients. Realizing this procedure before the administration of primary polichemotherapy would reduce the number of unnecesary lymphadenectomy in patients with negative sentinel lymph node. Methods: From January 2006 to May 2008, twenty-one patients with breast cancer on stage II-IIIA were included in the study. The median age was of 49 years (range 22–74y). The median palpable tumour size was of 3.5cm (range 1.8–6.0) and by ultrasonography 2.0cm (range 1.8–5.0cm.). Stage II:19 and Stage III:2 (cT:6.0cm.). Breast biopsy was performed in all cases with: IDC:20. G1:9 (42,8%), G:2:11(52%) and G3:1(4,76%). ER+:18 (85,7%), PR+:13 (61,9%), HER2 (+):6 (28,5) and triple negative:3 (14,2%).The scheme of treatment was: 4Epi: 90mg/M2 and Cyclophosphamide 600mg/M2 day 1/3w/4cycles, followed by paclitaxel (P) 100mg/M2 day 1/wekly/8. Trastuzumab was given during one year 4/2mg/Kg and started with (P). Tumorectomy and limphadenectomy was planned, followed by radiotherapy ± Hormonotherapy ± trastuzumab. Results: The 21 patients were evaluable for the analysis. The median sentinel lymph nodes resected was of 2 (range 2–6). The SLN biopsy was positive in 12 (57,1%) cases and negative in 9 (42,8%). Followed the primary chemotherapy, tumorectomy and axillary lymphadenectomy (AL) were performed in all 21 cases. The 12 positive SLN showed in the AL 9/12 (75%) pN0 and the 9 negative SLN showed in the AL 0/9 (0%) pN1. There were 4/20 (20%) completely pathological tumour response and 4/20 (20%) cases with only isolated malignant cells. The treatment was well tolerated with not a case of grade 3–4 toxicity. Conclusions: The primary chemotherapy given after the biopsy of sentinel lymph node was very effective showing in the lymphadenectomy a high percentage of pathologic negative lymph nodes (9/12) and an overall tumour response of 40% (8/20) with 4/20 (20%) completely pathological response and 4/20 (20%) cases with only isolated malignant cells.

No significant financial relationships to disclose.

Elevated levels of interleukin-2 receptor and intercellular adhesion molecule 1 in sera from a venezuelan cohort of patients with dengue

This study evaluated the levels of soluble interleukin-2 receptor (sIL-2R) and soluble intercellular adhesion molecule-1 (sICAM-1) in patients with dengue. Sera from 17 patients with dengue fever (DF), 15 with dengue hemorrhagic fever (DHF) and 12 healthy individuals were obtained. Increased levels of sIL-2R and sICAM-1 were found in patients with DF and DHF when compared to normal; those were not correlated with leukocytes, hepatic serum enzyme levels or haemostatic parameters. Levels of sIL-2R were related to the different grades of DHF. These results suggest that increased levels of sIL-2R and sICAM-1 are a common feature of dengue.

Rock phosphate solubilization and colonization of maize rhizosphere by wild and genetically modified strains of Penicillium rugulosum

Maize root colonization and phosphate solubilizing activity of the fungus Penicillium rugulosum were assessed in a greenhouse trial using soil-plant microcosms. The bacterial gene hph conferring resistance to hygromicin B was introduced by electroporation in the wild-type strain IR-94MF1 of P. rugulosum and one transformant, w-T3, was selected. Maize plants were grown for 5 weeks in a P-poor soil and fertilized with a Florida apatite mineral, with Navay, an apatite rock deposit from Venezuela, or with simple superphosphate. Inoculation treatments included strain IR-94MF1, transformant w-T3 and two IR-94MF1 UV-induced mutants with enhanced (Mps++) or reduced (Mps-) in vitro mineral phosphate solubilizing activity. In the absence of P fertilization, inoculation with any P. rugulosum isolate significantly reduced the size of the total and P-solubilizing bacterial community present in maize rhizosphere. The bacterial community significantly increased in maize inoculated with IR-94MF1 and w-T3 when P was added as apatites Navay or Florida. All P. rugulosum strains were able to stimulate the growth of maize plants as indicated by 3.6 to 28.6% increases in dry matter yields. In the presence of rock phosphate, P uptake by maize plants inoculated with the two mutants Mps++ and Mps- was not always in agreement with their P-solubilizing phenotypes. Strain IR-94MF1 and transformant w-T3 increased P assimilation by the plants fertilized with Navay rock phosphate by 26 and 38%, respectively. In this treatment, w-T3 showed its highest significant maize rhizosphere colonization. With the simple superphosphate treatment, w-T3 increased P uptake in plants by 8% over the uninoculated control and also decreased significantly the community size of total bacteria, total fungi, and P-solubilizing fungi in the rhizosphere.

Vasopressin-mediated regulation of epithelial sodium channel abundance in rat kidney

Sodium transport is increased by vasopressin in the cortical collecting ducts of rats and rabbits. Here we investigate, by quantitative immunoblotting, the effects of vasopressin on abundances of the epithelial sodium channel (ENaC) subunits (alpha, beta, and gamma) in rat kidney. Seven-day infusion of 1-deamino-[8-D-arginine]-vasopressin (dDAVP) to Brattleboro rats markedly increased whole kidney abundances of beta- and gamma-ENaC (to 238% and 288% of vehicle, respectively), whereas alpha-ENaC was more modestly, yet significantly, increased (to 142% of vehicle). Similarly, 7-day water restriction in Sprague-Dawley rats resulted in significantly increased abundances of beta- and gamma- but no significant change in alpha-ENaC. Acute administration of dDAVP (2 nmol) to Brattleboro rats resulted in modest, but significant, increases in abundance for all ENaC subunits, within 1 h. In conclusion, all three subunits of ENaC are upregulated by vasopressin with temporal and regional differences. These changes are too slow to play a major role in the short-term action of vasopressin to stimulate sodium reabsorption in the collecting duct. Long-term increases in ENaC abundance should add to the short-term regulatory mechanisms (undefined in this study) to enhance sodium transport in the renal collecting duct.

Adsorption of omeprazole on latex particles and characterization of the complex

Omeprazole is an antisecretory drug used against gastric ulcers. It quickly decomposes in an acid medium, however, therefore making it a matter of great interest to protect it in these conditions and determine the ideal adsorption conditions for this drug on latex particles for formulation designs--oral suspensions--containing polymers with the aim of delivering different drugs in a sustained and controlled action. Time, pH, and concentration of the active ingredient for which maximum adsorption occurs, were determined. The findings suggest that adsorption is evidently greatest at an acid pH 4-5, that the adsorption of Omeprazole rises concomitantly with the increase in latex particles, and the time is the least influential factor.

[Renal effects of prolonged sevoflurane anesthesia in Wistar rats]

OBJECTIVES

To assess renal safety of sevoflurane administered to Wistar rats at clinical concentrations during prolonged periods of inhalation.

MATERIAL AND METHODS

The experimental animals were assigned to two groups of six rats each. Group I received anesthesia with 1.5% sevoflurane for 6 hours and group II received the same concentration of sevoflurane for 15 hours. The anesthesia was inhaled in an open circuit of fresh air at 1 l/min (medicinal air, 22.75% O2). The animals were kept in metabolic cages throughout the nine days the experiment lasted. Weight and urine output were recorded daily and the day before anesthesia was started, inorganic fluoride and blood was analyzed for renal function (urea, sodium, and blood urea nitrogen [BUN]). Between two and three hours after withdrawal of anesthesia, inorganic fluoride was again assessed, and on the last day of the experiment a new blood sample was taken to evaluate renal function. Kidney tissue was then studied.

RESULTS

The two groups were similar as to weight, urea, sodium and BUN. Hourly diuresis was significantly greater after anesthesia in group II but not in group I. Inorganic fluoride was significantly higher in both groups, with postanesthetic levels of 22.42 +/- 1.76 microM/l in group I and 35.05 +/- 1.80 microM/l in group II. Renal tissue from both groups appeared normal under an optical microscope.

CONCLUSIONS

Sevoflurane at the doses tested increases inorganic fluoride concentrations although for both periods the levels stayed under 50 microM/l, which has been considered the nephrotoxic threshold. No signs of changes in renal function were observed in blood texts or tissue studies.

General medical advice for travelers

Millions of people travel to developing countries, many of which are in the tropics, where the risk of becoming injured or sick is markedly increased and the access to appropriate medical treatment is markedly decreased. There are also common medical problems that all travelers confront, no matter what their itinerary. This article describes several traveling strategies for treating some common medical problems, lowering risk, and being able to get help should an emergency occur. Preparation is the watchword for the traveler.

[The incidence of major histocompatibility system antigens in dilated and ischemic myocardiopathies]

AIM

The purpose of this study was to analyze the frequency of the different antigens of HLA in patients with diagnosis of very advanced dilated cardiomyopathy and ischemic heart disease by comparing them with a control group of supposedly healthy subjects.

MATERIAL AND METHOD

The group of dilated cardiomyopathy consisted of 35 patients (8 women and 27 men) aged between 14 and 60 years. The group of ischemic heart disease included 32 patients (4 women and 28 men) aged between 34 and 64 years. The control group comprised 1337 subjects of the Spanish Mediterranean area, supposedly healthy and recruited from paternity studies.

RESULTS

In dilated cardiomyopathy we found a higher incidence in comparison with the control group of the A-2 (62.86% vs 46.22%), B-12 (60.00% vs 32.38%) and DQ-3 (82.86 vs 49.96%) antigens, and a lower incidence of B-51 (0.00% vs 12.49%). In ischemic heart disease we found, when comparing to the control group, a higher incidence of A-11 (31.25% vs 13.08%) and A-29 (34.38% vs 14.58%) antigens and a lower incidence of DQ-2 (15.63% vs 49.88%).

CONCLUSIONS

In the Spanish Mediterranean area, the presence of A-2, B-12 and DQ-3 antigens, as well as the absence of B-51 would favour the appearance of advanced dilated cardiomyopathy. The presence of the A-11 and A-29 antigens would predispose to ischemic cardiomyopathy while the presence of DQ-2 would have a protective effect on the appearance of this cardiopathy.

[The use of cryopreserved homografts in reconstructing the right ventricular outflow tract in congenital cardiopathies]

In recent years the use of cryopreserved allograft valves has become very popular. Homograft valves have been used for aortic valve replacement and for reconstruction of the outflow tract of the right ventricle for more than 30 years with very good results. Recently the method of cryopreservation has made possible the creation of valve banks. The use of this cryopreserved valves has obtained very good short and medium term results. We present our experience with the use of cryopreserved allograft valves in the reconstruction of the right ventricular outflow tract in the treatment of complex cardiac malformations. We have operated 15 children. Six were diagnosed of different types of transpositions of the great arteries with ventricular septal defect and pulmonary atresia or stenosis. There were 2 deaths not related to the use of the allograft valves. Nine other patients were diagnosed of different types of complex cardiac malformations. One patient with a univentricular heart and pulmonary stenosis and a neonate presenting with a truncus arteriosus communis died after the operation; again the deaths were not related to the use of the homograft conduits. Our technique of cryopreservation consists in the procurement of aortic and pulmonary valves from multiorgan donor patients. The valves are sterilized in antibiotics for 48 hours. Then the process of freezing is began with a period of progressive cooling down to -40 degrees C and second phase of storage in liquid nitrogen to a temperature of -178 degrees C. The short and medium term results are very satisfactory. We have not seen late important complications.

Reduction of infection after cardiac surgery: a clinical trial

Between January 1, 1975, and June 1, 1984, 3,275 patients underwent cardiac operations with cardiopulmonary bypass. No operations were performed in 1978. In Phase I of the study, general operating rooms were used for cardiac operations, and standard methods of antisepsis and asepsis were used. Phase II began in January, 1979, with the opening of two specially constructed operating rooms with complete separation of incoming and outgoing personnel and supplies, and with a laminar airflow system. All personnel scrubbed 3 minutes and changed into autoclaved clothing before entering the operating suite, and scrubbed again for 5 minutes before putting on gowns. By Phase III, which began in July, 1982, all additional protocols against infection were in place including strict techniques in the intensive care unit and a continuous antiinfection surveillance program. In Phase I, 7.3% (70% confidence limits [CL] 6.4 to 8.2%) of patients had an infectious complication; in Phase II, 2.7% (CL 2.3 to 3.2%), and in Phase III, 0.8% (CL 0.5 to 1.2%). The reductions were similar in the four subtypes of infection (superficial presternal infection, mediastinitis, endocarditis, and septicemia). The study indicates that improving the surgical environment, improving the surgical and operating room protocols, and increasing the awareness of the dangers of infection among the personnel can strikingly reduce the incidence of infections after cardiac operations.