Oral Clonidine-Based Strategy to Reduce Opiate Use During Cooling for Neonatal Encephalopathy: An Observational Study.

OBJECTIVE: To determine whether an enteral, clonidine-based sedation strategy (CLON) during therapeutic hypothermia (TH) for hypoxic-ischemic encephalopathy would decrease opiate use while maintaining similar short-term safety and efficacy profiles to a morphine-based strategy (MOR). STUDY DESIGN: This was a single-center, observational study conducted at a level IV neonatal intensive care unit from January 1, 2017, to October 1, 2021. From April 13, 2020, to August 13, 2020, we transitioned from MOR to CLON. Thus, patients receiving TH for hypoxic-ischemic encephalopathy were grouped to MOR (before April 13, 2020) and CLON (after August 13, 2020). We calculated the total and rescue morphine milligram equivalent/kg (primary outcome) and frequency of hemodynamic changes (secondary outcome) for both groups. RESULTS: The MOR and CLON groups (74 and 25 neonates, respectively) had similar baseline characteristics and need for rescue sedative intravenous infusion (21.6% MOR and 20% CLON). Both morphine milligram equivalent/kg and need for rescue opiates (combined bolus and infusions) were greater in MOR than CLON (P < .001). As days in TH advanced, a lower percentage of patients receiving CLON needed rescue opiates (92% on day 1 to 68% on day 3). Patients receiving MOR received a greater cumulative dose of dopamine and more frequently required a second inotrope and hydrocortisone for hypotension. MOR had a lower respiratory rate during TH (P = .01 vs CLON). CONCLUSIONS: Our CLON protocol is noninferior to MOR, maintaining perceived effectiveness and hemodynamic safety, with an apparently reduced need for opiates and inotropes.

Perinatal Inflammatory Biomarkers and Respiratory Disease in Preterm Infants.

OBJECTIVE: To measure plasma levels of vascular endothelial growth factor (VEGF) and several cytokines (Interleukin [IL]-6 IL-8, IL-10) during the first week of life to examine the relationship between protein expression and likelihood of developing respiratory distress syndrome (RDS) and bronchopulmonary dysplasia (BPD). STUDY DESIGN: Levels of IL-6, IL-8, IL-10, and VEGF were measured from plasma obtained from preterm patients during the first week of life. Newborns were recruited from a single center between April 2009 and April 2019. Criteria for the study included being inborn, birth weight of less than 1500 grams, and a gestational age of less than 32 weeks at birth. RESULTS: The development of RDS in preterm newborns was associated with lower levels of VEGF during the first week of life. Higher plasma levels of IL-6 and IL-8 plasma were associated with an increased likelihood and increased severity of BPD at 36 weeks postmenstrual age. In contrast, plasma levels of VEGF, IL-6, IL-8, and IL-10 obtained during the first week of life were not associated with respiratory symptoms and acute care use in young children with BPD in the outpatient setting. CONCLUSIONS: During the first week of life, lower plasma levels of VEGF was associated with the diagnosis of RDS in preterm infants. Preterm infants with higher levels of IL-6 and IL-8 during the first week of life were also more likely to be diagnosed with BPD. These biomarkers may help to predict respiratory morbidities in preterm newborns during their initial hospitalization.

Structures of the fungal dynamin-related protein Vps1 reveal a unique, open helical architecture.

Dynamin-related proteins (DRPs) are large multidomain GTPases required for diverse membrane-remodeling events. DRPs self-assemble into helical structures, but how these structures are tailored to their cellular targets remains unclear. We demonstrate that the fungal DRP Vps1 primarily localizes to and functions at the endosomal compartment. We present crystal structures of a Vps1 GTPase-bundle signaling element (BSE) fusion in different nucleotide states to capture GTP hydrolysis intermediates and concomitant conformational changes. Using cryoEM, we determined the structure of full-length GMPPCP-bound Vps1. The Vps1 helix is more open and flexible than that of dynamin. This is due to further opening of the BSEs away from the GTPase domains. A novel interface between adjacent GTPase domains forms in Vps1 instead of the contacts between the BSE and adjacent stalks and GTPase domains as seen in dynamin. Disruption of this interface abolishes Vps1 function in vivo. Hence, Vps1 exhibits a unique helical architecture, highlighting structural flexibilities of DRP self-assembly.

[The impact of tap water fluoridation on human health]. / Consecuencias de la fluoración del agua potable en la salud humana.

The purpose of this review is to describe the osteological, neurological, endocrine and dermatological effects of fluoride ingestion. Additional aims are to evaluate whether the Chilean tap water fluoridation program has had any impact on dental health, and analyze the basis for the Chilean elementary school milk fluoridation program, which is targeted at children living in places where tap water has a fluoride concentration less than 0.3 mg/L, without any artificial fluoridation process. We discuss the finding that both public measures have no direct or remarkable effect on dental health, since topical dental hygiene products are the main and most effective contributors to the prevention of dental decay. We also suggest that the permanent and systematic ingestion of fluorides imposes health risks on the population. Therefore, we recommend reevaluating the national fluoridation program for public tap water and the elementary school milk program.

Consecuencias de la fluoración del agua potable en la salud humana / The impact of tap water fluoridation on human health

The purpose of this review is to describe the osteological, neurological, endocrine and dermatological effects of fluoride ingestion. Additional aims are to evaluate whether the Chilean tap water fluoridation program has had any impact on dental health, and analyze the basis for the Chilean elementary school milk fluoridation program, which is targeted at children living in places where tap water has a fluoride concentration less than 0.3 mg/L, without any artificial fluoridation process. We discuss the finding that both public measures have no direct or remarkable effect on dental health, since topical dental hygiene products are the main and most effective contributors to the prevention of dental decay. We also suggest that the permanent and systematic ingestion of fluorides imposes health risks on the population. Therefore, we recommend reevaluating the national fluoridation program for public tap water and the elementary school milk program.

Patch testing in children from 2005 to 2012: results from the North American contact dermatitis group.

BACKGROUND: Allergic contact dermatitis is common in children. Epicutaneous patch testing is an important tool for identifying responsible allergens. OBJECTIVE: The objective of this study was to provide the patch test results from children (aged ≤18 years) examined by the North American Contact Dermatitis Group from 2005 to 2012. METHODS: This is a retrospective analysis of children patch-tested with the North American Contact Dermatitis Group 65- or 70-allergen series. Frequencies and counts were compared with previously published data (2001-2004) using χ statistics. CONCLUSIONS: A total of 883 children were tested during the study period. A percentage of 62.3% had ≥1 positive patch test and 56.7% had ≥1 relevant positive patch test. Frequencies of positive patch test and relevant positive patch test reaction were highest with nickel sulfate (28.1/25.6), cobalt chloride (12.3/9.1), neomycin sulfate (7.1/6.6), balsam of Peru (5.7/5.5), and lanolin alcohol 50% petrolatum vehicle (5.5/5.1). The ≥1 positive patch test and ≥1 relevant positive patch test in the children did not differ significantly from adults (≥19 years) or from previously tested children (2001-2004). The percentage of clinically relevant positive patch tests for 27 allergens differed significantly between the children and adults. A total of 23.6% of children had a relevant positive reaction to at least 1 supplemental allergen. Differences in positive patch test and relevant positive patch test frequencies between children and adults as well as test periods confirm the importance of reporting periodic updates of patch testing in children to enhance clinicians' vigilance to clinically important allergens.

Interaction of LDS-751 with the drug-binding site of P-glycoprotein: a Trp fluorescence steady-state and lifetime study.

P-glycoprotein (ABCB1) is an ATP-driven efflux pump which binds drugs within a large flexible binding pocket. Intrinsic Trp fluorescence was used to probe the interactions of LDS-751 (2-[4-(4-[dimethylamino]phenyl)-1,3-butadienyl]-3-ethylbenzo-thiazolium perchlorate) with purified P-glycoprotein, using steady-state/lifetime measurements and collisional quenching. The fast decay component of P-glycoprotein intrinsic fluorescence (tau(1)=0.97 ns) was unaffected by LDS-751 binding, while the slow decay component (tau(2)=4.02 ns) was quenched by dynamic and static mechanisms. Both the wavelength-dependence of the decay kinetics, and the time-resolved emission spectra, suggested the existence of excited-state relaxation processes within the protein matrix on the nanosecond time-scale, which were altered by LDS-751 binding. The fast decay component, which is more solvent-exposed, can be attributed to cytosolic/extracellular Trp residues, while the slow decay component likely arises from more buried transmembrane Trp residues. Interaction of a drug with the binding pocket of P-glycoprotein thus affects its molecular structure and fast dynamics.

Interaction of LDS-751 and rhodamine 123 with P-glycoprotein: evidence for simultaneous binding of both drugs.

The P-glycoprotein efflux pump, an ABC superfamily member, can export a wide variety of hydrophobic drugs, natural products, and peptides from cells, powered by the energy of ATP hydrolysis. Transport substrates appear to first partition into the membrane and then interact with the protein within the cytoplasmic leaflet. Two drug binding sites within P-glycoprotein have been described which interact allosterically, the H-site (binds Hoechst 33342) and the R-site (binds rhodamine 123); however, the structural and functional relationship between the various binding sites appears complex. In this work, we have used fluorescence spectroscopic approaches to characterize the interaction of the transporter with LDS-751 and rhodamine 123, both of which are believed to bind to the putative R-site based on functional transport studies. By carrying out single and sequential dual fluorescence titrations of purified P-glycoprotein with the two substrates, we observed that bound LDS-751 interacted with bound rhodamine 123. Rhodamine 123 and LDS-751 showed a reciprocal negative interaction, each reducing the binding affinity of the other by 5-fold, indicating that the two compounds were simultaneously bound to the protein to form a ternary complex. Fitting of the dependence of the apparent Kd for LDS-751 binding on rhodamine 123 concentration suggested that the two compounds interacted noncompetitively. We conclude that the two-site drug binding model for P-glycoprotein requires modification. The putative R-site appears large enough to accommodate two compounds simultaneously. The locations where LDS-751 and rhodamine 123 bind are likely adjacent to each other, possibly overlapping, and may be within a hydrophobic pocket.

Interaction of LDS-751 with P-glycoprotein and mapping of the location of the R drug binding site.

One cause of multidrug resistance is the overexpression of P-glycoprotein, a 170 kDa plasma membrane ABC transporter, which functions as an ATP-driven efflux pump with broad specificity for hydrophobic drugs, peptides, and natural products. The protein appears to interact with its substrates within the membrane environment. Previous reports suggested the existence of at least two binding sites, possibly overlapping and displaying positively cooperative interactions, termed the H and R sites for their preference for Hoechst 33342 and rhodamine 123, respectively. In this work, we have used several fluorescence approaches to characterize the molecular interaction of purified P-glycoprotein (Pgp) with the dye LDS-751, which is proposed to bind to the R site. A 50-fold enhancement of LDS-751 fluorescence indicated that the protein binding site was located in a hydrophobic environment, with a polarity lower than that of chloroform. LDS-751 bound with sub-micromolar affinity (K(d) = 0.75 microM) and quenched P-glycoprotein intrinsic Trp fluorescence by 40%, suggesting that Trp emitters are probably located close to the drub-binding regions of the transporter and may interact directly with the dye. Using a FRET approach, we mapped the possible locations of the LDS-751 binding site relative to the NB domain active sites. The R site appeared to be positioned close to the membrane boundary of the cytoplasmic leaflet. The location of both H and R drug binding sites is in agreement with the idea that Pgp may operate as a drug flippase, moving substrates from the inner leaflet to the outer leaflet of the plasma membrane.

Cinética del enlazamiento de H33342 a la p-glicoproteína: detección y análisis de curvas de progreso / Kinetic of the binding of H33342 to the p-glycoprotein: detection and analysis of progress curves

El transportador multidrogas P-glicoproteína (Pgp) lleva a cabo el eflujo celular, ATP-dependiente, de muchas drogas hidrofóbicas, productos naturales y péptidos. Se propone que la Pgp contiene dos sitios de transporte, conocidos como los sitios -H y -R por sus preferencias por Hoechst 33342 (H33342) y rodamina 123, respectivamente. Cuando H33342 interactúa con la Pgp purificada, su rendimiento cuántico incrementa debido al ambiente hidrofóbico del bolsillo de enlazamiento –H. En este trabajo, estudiamos el enlazamiento de H33342 a la Pgp empleando experimentos cinéticos en la modalidad de stoppedflow. El curso temporal de la reacción fue seguido por el incremento de la fluorescencia del colorante y analizado con la herramienta computacional DYNAFIT, usando un modelo donde una reacción bimolecular rápida, es seguida por tres isomerizaciones secuenciales. Adicionalmente, bajo condiciones de seudo-primer-orden (exceso del ligando), la reacción presentó cuatro relajaciones caracterizadas por cuatro constantes de tiempo (á`s) y cuatro amplitudes (A¡`s) Estos parámetros fueron analizados utilizando la técnica de la matriz de los operadores de proyección. Esta aproximación aportó, por primera vez, información acerca de las constantes de velocidad y propiedades fluorescentes de los diversos intermediarios formados durante el enlazamiento de H33342 a la Pgp.

The P-glycoprotein multidrug transporter (Pgp) carries out ATP-driven cellular efflux of many different hydrophobic drugs, natural products, and peptides. Pgp is proposed to contain two drug transport sites, known as the H site and the R site for their preference for Hoechst 33342 (H33342) and rhodamine 123, respectively. When H33342 interacts with purified Pgp, its quantum yield is increased due to transfer to a hydrophobic environment within the H binding pocket, as shown by the steady-state fluorescence emission. In this work, we studied the binding of H33342 to Pgp using stopped-flow kinetic experiments. The time course of the reaction was followed by enhancement of dye fluorescence and analyzed by the computational tool DYNAFIT, using the model of a fast bimolecular reaction, followed by a three-step sequential isomerization. Additionally, under pseudo-first-order conditions (excess ligand), the reaction presented five normal modes, characterized by four relaxation times (á`s) and four amplitudes (A¡`s) These parameters were analyzed using the matrix projection operator technique, considering a four-step sequential reaction. This approach provides, for the first time, information about the rate constants and fluorescent properties of the diverse intermediates formed during the binding of H33342 to Pgp.

Pediatric mood and anxiety syndromes in primary care: who gets identified?.

OBJECTIVE: To seek clues to the enhancement of primary care management by (i) Determining how often and in whom primary care clinicians in the United States, Puerto Rico, and Canada identify pediatric mood or anxiety syndromes; (ii) Determining which clinical and demographic features predict higher rates of identification; (iii) Describing assessment methods used. METHODS: This report uses the database of the multi-site Child Behavior Study. This cross-sectional study involved 206 primary care practices in the United States, Puerto Rico, and Canada; 395 clinicians and 20,861 primary care attenders aged 4-15 years. Clinicians completed a visit questionnaire addressing presence and type of psychosocial problems and how assessed. Parents completed a questionnaire addressing family demographics, child symptoms (Pediatric Symptom Checklist) and functioning, and child service use. RESULTS: Clinicians identified psychosocial problems on 17.9% of visits, but mood or anxiety syndromes on only 3.3%, most commonly in children judged to have co-morbid behavioral syndromes, of whom the majority (66.7%) already had contact with specialized mental health. Neither parental concerns about mood and anxiety symptoms nor clinician familiarity with the patient were major predictors of identification. When making a diagnosis of a pure internalizing syndrome (i.e., without a co-morbid behavioral syndrome) clinicians rarely used standardized tools or school reports. CONCLUSIONS: Neither screening for nor diagnosis of mood and anxiety syndromes is a routine part of primary care of children and adolescents. Efforts to improve care must include practical, validated screening procedures to enhance assessment for mood and anxiety syndromes, particularly among children in whom primary care clinicians identify psychosocial problems.

Síndrome de transfusión feto-fetal / Feto-fetal transfusion syndrome

Se realiza un análisis del síndrome de transfusión feto-fetal y se expone un caso clínico que finalizó en mortinato, demostrándose la gravedad y complejidad de esta patología. se destacan las características clínicas patogénicas, alternativas diagnósticas y eventuales opciones terapéuticas con sus respectivos riesgos, se hace referencia a las múltiples y graves complicaciones post natales

Síndrome de Dandy-Walker / Dandy-Walker's syndrome

El síndrome de Dandy-Walker es una malformación cerebral congénita que compromete el cerebelo y el IV ventrículo. Su incidencia estimada es de 1 en 25 mil a 35 mil embarazos con una prevalencia en mujeres de 3:1. Constituye una de las principales causas de hidrocefalia congénita. Se estima que aproximadamente un 5 a 10 por ciento de hidrocefalias corresponden a esta patología. El síndrome puede ser diagnosticado in utero mediante ultrasonografía. Su etiología es multifactorial, infecciosa, cromosómica y ambiental. Su diagnóstico de certeza está dado por la separación de los hemisferios cerebelosos por un IV ventriculo agrandado. En los pacientes portadores del síndrome se observa un severo retraso mental y una parálisis cerebral espástica; además puede asociarse a otras malformaciones de diferentes sistemas

Analysis of the interacting components between larval Schistosoma mansoni and schistosome-susceptible and resistant Biomphalaria glabrata

Cell-free hemolymph (serum) and hemocytes from Schistosoma mansoni-susceptible (PR albino M-line) and resistant (10-R2) strains of Biomphalaria glabrata were compared by SDS-PAGE, immunoblotting and radioiodination. Whole serum of both snail strains is dominated by hemoglobin (Hb) (MW = 160 Kd). SDS-PAGE. of Hb-depleted serum indicated that the 10-R2 strain has dominant polypeptides in the 50 to 30 Kd range whereas PR albino snails have few low MW proteins. Antibodies raised to whole PR albino and 10-R2 serum, and the 160 Kd (Hb) band reacted similarly in immunoblot assays. Analysis of hemocytes revealed that 10-R2 snails have a surface-exposed protein at about 80 Kd which is not present on PR albino hemocytes. An examination of primary cultured sporocysts indicated the presence of four major surface proteins (40, 50, 55, 70 Kd) and two minor surface-exposed polypeptides (92, 170 Kd). Antibodies raised against live, intact sporocysts reacted almost exclusively with sporocyst-surface proteins when tested by immunoblotting.

Use and abuse of systemic corticosteroid therapy

Steroid-responsive acute dermatoses should be treated with a single morning dose of prednisone for approximately 2 weeks. It is necessary to "taper" a short course of oral prednisone given by this method. Chronic dermatoses should be treated whenever possible with prednisone used in the morning and on alternate days. This method is effective, is free of most side effects, and suppresses the HPA axis minimally. There are few real advantages in using intramuscular corticosteroids. TAC is an unusually strong suppressor of the HPA axis. For chronic dermatoses, a less suppressive preparation might best be chosen if the physician feels that the intramuscular route is the most reasonable one. In any event TAC should never be used more often than every two months. Finally, the time-course of HPA recovery following short courses of steroids is presently unknown. Nonetheless, some astute critics of steroid metabolism have felt obliged to advise us that individuals who have received from 1 to 4 weeks of suppressive steroid treatment should be suspect as to the integrity of their HPA axis in stressful situations for up to one year. The withdrawal from, as well as the use of, systemic corticosteroids requires a creative and critical physician.