Auricular alloplastic reconstruction with osteointegrated implants: a new therapy option in microtia

Microtia has been treated over the years with autogenous tissues, although the results continue to improve, it is technically a very demanding procedure, even in the hands of a well trained surgeon. Osseointegrated implant-supported ear prosthesis, is less demanding, more straightforward, and offers a better cosmetic result. Since 1996 we have treated 8 patients with microtia types III and IV, with titanium osseointegrated implant-supported ear prosthesis in the bone of the mastoid process. The surgical procedure consists in two stages. First stage: when the three titanium screws are drill in the mastoid process of the temporal bone, with a previous CT scan of the area, that is used to measured the bone thickness. Second stage is done 3 to 6 months later. Ear remnants are removed at the beginning of the procedure, three titanium couplings are then secured to the integrated fixtures, a plastic cap is attached to each of the abutments, until healing takes place; three to four weeks later the auricular prosthesis made out of silicone over a metallic structure, will we plug in the titanium screws. Cosmetic results and patients acceptability have been good in all 8 cases, with few postoperative complications. This procedure has become and option for the patients with ear malformations.     

Pain and pain management in newborn infants: a survey of physicians and nurses

BACKGROUND: Despite an increased awareness among clinicians regarding pain and pain management for infants undergoing surgery, pain associated with procedures performed outside the operating room may not be adequately managed. PURPOSE: To examine the beliefs and self-described behavior of physicians and nurses regarding the management of procedural pain in newborn infants. METHODS: A survey was distributed to 467 clinicians (nurses and physicians) working in 11 level II and 4 level III nurseries in a large metropolitan area. Respondents were asked to rate the painfulness of 12 common bedside nursery procedures and how often pharmacologic and nonpharmacologic (comfort) measures are currently used and should be used for those procedures. Demographic data were also collected. RESULTS: Surveys were completed by 374 clinicians (80% response rate). Physicians and nurses believe infants feel as much pain as adults and that 9 of the 12 listed procedures are moderately to very painful. Neither pharmacologic nor comfort measures are believed to be used frequently, even for the most painful procedures. Physicians and nurses believe both pharmacologic and comfort measures should be used more frequently, but nurses believe comfort measures should be used more frequently than do physicians. Beliefs about infant pain and procedural pain were related to pain management preferences. Physicians' but not nurses' ratings were associated with significant personal pain. CONCLUSIONS: Despite their beliefs that infants experience significant procedure-related pain, clinicians believe pain management for infants remains below optimal levels. Barriers to more consistent and effective pain management need to be identified and surmounted.     

Bacterial and mammalian DNA alkyltransferases sensitize Escherichia coli to the lethal and mutagenic effects of dibromoalkanes

Here we confirm and extend our previous studies demonstrating that the mutagenic potency of 1,2-dibromoethane (DBE) and dibromomethane (DBM) is markedly enhanced (not prevented) in bacteria expressing the O6- alkylguanine-DNA alkyltransferase (ATase) encoded by the Escherichia coli ogt gene. We demonstrate that, in close parallel with mutagenesis, the Ogt ATase sensitizes the bacteria to the lethal effects of these carcinogens, suggesting that one or more of the potentially mutagenic lesions induced by DBE and DBM in the presence of Ogt has additional lethal capacity. We further demonstrate that the sensitization to both lethality and mutagenesis by DBE and DBM is a property shared by other DNA alkyltransferases. This objective was accomplished by quantifying the induction of mutations and lethal events in ogt- ada- E. coli expressing an exogenous bacterial or mammalian ATase from a multicopy plasmid. Mammalian recombinant ATases enhanced the lethal and mutagenic actions of DBE and suppressed the lack of sensitivity of the vector- transformed bacteria to DBM. In most cases the order of effectiveness of the ATases ranked: murine > human > Ogt > rat. Further comparisons included the full-length Ada ATase from E. coli and a truncated Ada version (T-ada) that retains the O6-methylguanine binding domain of the protein. The full-length Ada ATase was effective in enhancing the lethality but not the mutagenicity induced by DBE and DBM. The T-ada ATase provided less sensitization than Ada to lethality by DBE, but of the three bacterial ATases T-ada yielded the highest sensitization to mutagenesis by this compound. T-ada and Ada ATases were in general less effective than the mammalian versions, with the exception of the rat recombinant ATase. The effectiveness of the different mammalian and bacterial ATases in promoting the deleterious actions of dibromoalkanes was compared with the effectiveness of these proteins in suppressing the lethal and mutagenic effects induced by N-nitroso-N-methylurea. The ability to sensitize E. coli to the lethal and mutagenic effects of DBE and DBM seems restricted to DNA alkyltransferase, since overexpression of thioredoxin (Trx) or glutaredoxin (Grx1) in ogt- ada- cells showed no effect, in spite of the reported potential of bioactive dihaloethane- derived species to alkylate Trx.      

Prevention of central venous catheter-related bloodstream infections using non-technologic strategies.

OBJECTIVE: To evaluate the incidence of nosocomial bacteremias related to the use of non-impregnated central venous catheters (CVCs) when only non-technologic strategies were used to prevent them. DESIGN: This was a prospective study of infectious complications of CVCs placed in intensive care unit (ICU) patients from April 1997 to December 2001. SETTING: The medical-surgical ICU of a tertiary-care, university-affiliated hospital in Argentina. METHODS: We studied all patients admitted to the ICU using non-impregnated CVCs. Maximal sterile barrier precautions (ie, use of cap, mask, sterile gown, sterile gloves, and large sterile drape), strict handwashing, preparation of the patients' skin with antiseptic solutions, insertion and management of catheters by trained personnel, and continuing quality improvement programs aimed at appropriate insertion and maintenance of catheters were employed. RESULTS: During the study period, 2,525 patients were admitted to the ICU. Eight hundred sixty-eight patients had 1,037 CVCs inserted. The number of CVC-related bloodstream infections (BSIs), acquired in the ICU, was 2.7 per 1,000 CVC-days (13 nosocomial CVC-related BSIs during 4,770 days of CVC use). Microorganisms isolated included methicillin-susceptible Staphylococcus aureus (n = 6), methicillin-resistant S. aureus (n = 2), coagulase-negative methicillin-resistant Staphylococcus (n = 2), Escherichia coli (n = 1), Klebsiella pneumoniae (n = 1), and Enterobacter cloacae (n = 1). CONCLUSIONS: A low rate of catheter-related BSI was achieved without antimicrobial-impregnated catheters. The incidence of CVC-associated bacteremias corresponded to the 10th to 20th percentile range of the National Nosocomial Infections Surveillance System hospitals for the same type of ICU.     

A robotic manipulator for the characterization of two-dimensional dynamic stiffness using stochastic displacement perturbations

Experimental techniques for estimating the two-dimensional dynamic stiffness of the human arm over a wide range of conditions have been developed. A robotic manipulator has been developed to create loads against which subjects perform various tasks and also to impose perturbations onto the endpoint of the arm to allow estimation of its mechanical properties. The manipulator can produce static endpoint forces exceeding 220 N in any direction in its plane of motion, and this plane can be vertically translated and tilted over wide ranges to study arm dynamic stiffness in many functionally relevant planes. It can impose stochastic position and force perturbations whose bandwidth exceeds that of the arm. These random perturbations avoid undesirable volitional reactions and allow the efficient estimation of stiffness dynamics using experimental trials of short duration. The ability of this manipulator to characterize inertial-viscoelastic systems was tested using several two-dimensional physical systems whose properties were independently characterized. The endpoint dynamic stiffness properties of a human arm were estimated as an example of the use of the manipulator in studying upper limb mechanical properties. The system properties characterized by these methods will be useful in probing normal neural arm control strategies and in developing rehabilitation interventions to improve arm movements in disabled individuals.     

Neurophysiological monitoring during scoliosis surgery using controlled hypotension

Controlled arterial hypotension understood to be a mean arterial pressure (MAP) between 55 and 60 mmHg is often used as a complementary technique in anesthesia even though it is not without complications and associated mortality even in young patients. During surgery to reduce scoliosis in a young boy, MAP fell to 60 mmHg accompanied by bilateral loss of sensory and motor evoked potentials (SEP and MEP). Detecting the absence of SEP and MEP allowed us to prevent medullar injury due to ischemia secondary to hypotension, once possible surgical or technical causes had been ruled out. We believe that monitoring SEP and MEP is useful not only to the surgeon but also to the anesthesiologist.     

Deprescripción en personas mayores: es el momento de pasar a la acción

El uso de fármacos conlleva innegables beneficios en las personas mayores, pero no está exento de efectos indeseables. La deprescripción es el proceso de revisión sistemática de la medicación con el objetivo de lograr la mejor relación riesgo-beneficio en base a la mejor evidencia disponible. Este proceso es especialmente importante en mayores polimedicados, sobretratados, frágiles, con enfermedades terminales y en el final de la vida.La deprescripción debe hacerse de forma escalonada, estableciendo un seguimiento estrecho por si aparecen problemas tras la retirada. En la toma de decisiones es muy importante contar con la opinión del paciente y de los cuidadores, valorando los objetivos del tratamiento según la situación clínica, funcional y social del enfermo.Existen múltiples herramientas para facilitar a los clínicos la tarea de seleccionar qué fármacos deprescribir (criterios Beers, STOPP-START…). Los grupos farmacológicos más susceptibles de intervención son: antihipertensivos, antidiabéticos, estatinas, benzodiacepinas, antidepresivos, anticolinérgicos, anticolinesterásicos y neurolépticos.Palabras clave: Polifarmacia, Envejecimiento, Comorbilidad, Prescripción inadecuada, Efectos adversos, Deprescripción     

SARS-CoV-2 Variants in Paraguay: Detection and Surveillance with an Economical and Scalable Molecular Protocol

SARS-CoV-2 variant detection relies on resource-intensive whole-genome sequencing methods. We sought to develop a scalable protocol for variant detection and surveillance in Paraguay, pairing rRT-PCR for spike mutations with Nanopore sequencing. A total of 201 acute-phase nasopharyngeal samples were included. Samples were positive for the SARS-CoV-2 N2 target and tested with the Spike SNP assay to detect mutations associated with the following variants: alpha (501Y), beta/gamma (417variant/484K/501Y), delta (452R/478K), and lambda (452Q/490S). Spike SNP calls were confirmed using amplicon (Sanger) sequencing and whole-genome (Nanopore) sequencing on a subset of samples with confirmed variant lineages. Samples had a mean N2 Ct of 20.8 (SD 5.6); 198/201 samples (98.5%) tested positive in the Spike SNP assay. The most common genotype was 417variant/484K/501Y, detected in 102/198 samples (51.5%), which was consistent with the P.1 lineage (gamma variant) in Paraguay. No mutations (K417 only) were found in 64/198 (32.3%), and K417/484K was identified in 22/198 (11.1%), consistent with P.2 (zeta). Seven samples (3.5%) tested positive for 452R without 478K, and one sample with genotype K417/501Y was confirmed as B.1.1.7 (alpha). The results were confirmed using Sanger sequencing in 181/181 samples, and variant calls were consistent with Nanopore sequencing in 29/29 samples. The Spike SNP assay could improve population-level surveillance for mutations associated with SARS-CoV-2 variants and inform the judicious use of sequencing resources.