[Epidemiology and Outcomes of Soft Tissue Sarcomas: Insights from a Decade of Head and Neck Surgery at Sótero del Río Hospital, Santiago, Chile]. / Sarcomas de partes blandas: Análisis de la experiencia de diez años del equipo de cirugía de cabeza y cuello en el Hospital Sótero del Río.

BACKGROUND: Soft tissue sarcomas (STS) are rare malignant tumors of mesenchymal origin. They are associated with genetic and environmental risk factors. Their clinical manifestations are nonspecific, requiring a high level of suspicion. The first-line treatment is surgical. Positive margins are the only independent predictor of local recurrence and worse survival rates. Strict follow-up is recommended due to its high recurrence rate. AIM: Analyze the casuistry of STS treated with curative intent by the head and neck surgery team at the Sótero del Río Hospital (HSR) at Santiago, Chile between 2013 and 2023. METHODS: A retrospective, descriptive study of patients with STS managed by the HSR head and neck surgery team. Clinical presentation, diagnostic and therapeutic tools, and oncological results are analyzed. RESULTS: 26 patients were included, 84.6% female, with an average age of 61.7 years. Only 30.8% presented identifiable risk factors. The most common histology was undifferentiated pleomorphic sarcoma (26.9%), and the predominant location was extremities (46.2%). 77.8% of head and neck sarcomas and 58.8% of trunk and extremity sarcomas occurred in advanced stages. Disease-free survival was 66.6%; 68.2% in patients with negative surgical margins, and 60.0% in positive margins at five years. CONCLUSIONS: STS is an infrequent pathology. This study corresponds to the first retrospective research on STS in Chile. We require establishing a specialized multidisciplinary team to optimize the management and follow-up of STS patients.

Sublethal effects in Perinereis gualpensis (Polychaeta: Nereididae) exposed to mercury-pyrene sediment mixture observed in a multipolluted estuary.

Sediment-living organisms can be subjected to a multi-pollution condition due to an increase in the diversity of contaminants. Sediment mixtures of Mercury (Hg) and some polycyclic aromatics hydrocarbons like Pyrene (Pyr) are common in heavily industrialized coastal zones. In the present study, greater than (>) and less than (<) probable effect concentration levels (PELs) of Hg and Pyr were assessed using spiked sediments in order to determine combined (Hg + Pyr) effects in uptake, metabolization and oxidative balance in the polychaete Perinereis gualpensis at short and medium-term exposure. Hg + Pyr significantly influenced the uptake/kinetics of Hg and Pyr metabolite 1-OH-pyrene in polychaete tissues during the exposure time compared with separate treatments of each analyte (p < 0.05). Both the Hg-only and Pyr-only exposures significantly influenced both enzymatic and non-enzymatic responses respect to control groups (p < 0.05). The Hg-only treatment showed the worst scenario related to the activation and subsequent inhibition of glutathione S- transferase (GST) and peroxidase (GPx) activities, high levels of Thiol-groups (SH-groups), low antioxidant capacity (ACAP) and enhanced lipid peroxidation (TBARS) in the last days of exposure (p < 0.05). In contrast, ragworms exposed to Hg + Pyr showed a significant increase in both enzymatic and non-enzymatic activity during the first days of exposure and the absence of lipid peroxidation during the whole experiment. Our results suggest different oxidative stress scenarios in P. gualpensis when exposed to >PEL Hg concentration with

Patients with prior vertebral or hip fractures treated with teriparatide in the Direct Assessment of Nonvertebral Fractures in Community Experience (DANCE) observational study.

SUMMARY: In patients in the Direct Assessment of Nonvertebral Fractures in Community Experience (DANCE) observational study with and without a prior vertebral or hip fracture, the incidence of nonvertebral fractures was lower with >6 months of teriparatide treatment than during the first 6 months. INTRODUCTION: Clinical evidence on the effect of teriparatide in patients with prior fracture is limited. In the DANCE observational study, the incidence of nonvertebral fragility fractures (NVFX) decreased significantly in patients receiving teriparatide for >6 months (6-24 months) versus >0 to ≤6 months (reference period). METHODS: We performed a post hoc analysis to assess the effect of teriparatide 20 µg/day in patients who entered DANCE with prior vertebral or hip fractures. The incidence of patients experiencing a NVFX for four 6-month intervals during and after treatment was compared with the reference period. RESULTS: Overall, 4085 patients received ≥1 dose of teriparatide. Of 3720 with sufficient data for efficacy analysis, 692 had prior vertebral fracture, including 179 with previous kyphoplasty/vertebroplasty; 290 had prior hip fracture. These patients were older, and those with prior vertebral fractures had more comorbid conditions at baseline than those without prior vertebral fractures. The incidence of patients experiencing NVFX declined over time in all patient groups. The fracture incidence rate declined 49 and 46%, respectively, in patients with and without prior vertebral fracture and was 63 and 46% lower in patients with previous kyphoplasty/vertebroplasty and without prior vertebral fracture. NVFX declined 43 and 48% in patients with and without prior hip fracture. The reduced incidence over time was consistent in the subgroups (all interaction p values >0.05). Patients with prior fracture were more likely to experience serious adverse events. CONCLUSION: The incidence of NVFX decreased over time in patients receiving teriparatide in DANCE regardless of prior fracture status.

Differential response of two somatolactin genes to zinc or estrogen in pituitary of Cyprinus carpio.

Environmental changes affect gene expression that we addressed in the pituitary, a central regulatory organ at the interface between the central nervous system and the endocrine system. With the aim to reveal effects of changes in the aquatic environment on the expression of hypothalamo-hypophyseal factors, we characterized somatolactin (SL) in Cyprinus carpio. SL, a fish specific pituitary hormone belonging to the prolactin (PRL) superfamily, is involved in background adaptation, osmoregulation, reproduction and fatty acid metabolism. Two sl genes, α and ß, were discovered in carp and transcripts of both were detected in pituitaries. Clearly, expression of slα and slß was modulated significantly in pituitary of male adult carp in response to treatment with ZnCl2 (Zn), but only slß responded to 17ß-estrogen (E2), relative to control carp as shown by RT-qPCR analyses. Furthermore, the amount of mRNA of related factors was assessed revealing variable effects on prl, growth hormone (gh), and factors involved in sl regulation: the pituitary transcription factor pit1 and hypothalamic pituitary adenylase cyclase activating peptide (pacap). In parallel, the physiological response of the experimental animals to Zn or E2 was confirmed by showing a significant increase of metallothionein (mt) or vitellogenin (vg) gene expression in liver, classical sentinels for exposure to heavy metal or estrogens. These data suggest that the sl genes seem to be involved in the response to Zn, as well as to estrogen, and could contribute to evaluate biological relevant changes in the aquatic environment.

Foam sclerosants are more stable at lower temperatures.

OBJECTIVES: Sclerosant foams are aqueous and break down under the influence of gravity, pressure, and temperature. The aim of this study was to investigate the effects of temperature on foam stability. METHODS: Sodium tetradecyl sulphate (STS) and polidocanol (POL) liquid and foam (1 + 4, liquid-plus-air fraction) were investigated in a range of concentrations (0.5%, 1.5%, 3.0%) and temperatures. Surface tension was measured by the Du Nuoy ring method. Liquid drainage from foam was measured and documented by serial photography. Both pre- and post-cooling variations were investigated. RESULTS: Surface tension decreased at higher temperatures. Surface tension of POL was higher than STS at concentrations tested. POL foam half-time increased significantly at higher concentrations while the half-time of STS foam was not affected by concentration. Heating the sclerosant foam above the ambient temperature reduced its half-time while cooling below the ambient temperature prolonged the half-time. Both pre- and post-cooling of the foams resulted in significant prolongation of half-times when compared to no cooling. Maximum stability of the two sclerosant foams tested was achieved at 10 °C. CONCLUSIONS: Foam sclerosants are more stable at cooler temperatures.

Melatonin exerts direct inhibitory actions on ACTH responses in the human adrenal gland.

In nonhuman primates and rodents, melatonin acting directly on the adrenal gland, inhibits glucocorticoid response to ACTH. In these species, an intrinsic adrenal circadian clock is involved in ACTH-stimulated glucocorticoid production. We investigated whether these findings apply to the human adrenal gland by determining i) expression of clock genes in vivo and ii) direct effects of melatonin in ACTH-stimulated adrenal explants over a) expression of the clock genes PER1 (Period 1) mRNA and BMAL1 [Brain-Muscle (ARNT)-like] protein, ACTH-induced steroidogenic acute regulatory protein (StAR), and 3ß-hydroxysteroid dehydrogenase (3ß-HSD) and b) over cortisol and progesterone production. Adrenal tissue was obtained from 6 renal cancer patients undergoing unilateral nephrectomy-adrenalectomy. Expression of the clock genes PER1, PER2, CRY2 (Cryptochrome 2), CLOCK (Circadian Locomotor Output Cycles Kaput) and BMAL1, was investigated by RT-PCR in a normal adrenal and in an adenoma. In independent experiments, explants from 4 normal adrenals were preincubated in culture medium (6 h) followed by 12 h in: medium alone; ACTH (100 nM); ACTH plus melatonin (100 nM); and melatonin alone. The explants' content of PER1 mRNA (real-time PCR) and StAR, 3ß-HSD, BMAL1 (immuno slot-blot), and their cortisol and progesterone production (RIA) were measured. The human adrenal gland expresses the clock genes PER1, PER2, CRY2, CLOCK, and BMAL1. ACTH increased PER1 mRNA, BMAL1, StAR, and 3ß-HSD protein levels, and cortisol and progesterone production. Melatonin inhibited these ACTH effects. Our study demonstrates, for the first time, direct inhibitory effects of melatonin upon several ACTH responses in the human adrenal gland.

[Assessment of the impact of event scale revised for post traumatic stress disorder in Chilean subjects]. / Adaptación y validación de la versión chilena de la escala de impacto de evento-revisada (EIE-R).

BACKGROUND: Impact of Event Scale Revised (IES-R), that evaluates the subjective perception of stress, is used to assess post traumatic stress disorder simptoms. AIM: To adapt and validate IES-R to the Chilean population. MATERIAL AND METHODS: Two hundred seventy eight subjects exposed to stressful life events of varying magnitude were assessed using the IES-R, the Beck Depression Inventory, the anxiety and somatoform subscales of the Depressive, Anxiety and Somatoform Disorders Scale and the AUDIT Questionnaire. RESULTS: IES-R had adequate psychometric properties in terms of internal consistency, test-retest reliability, convergent and discriminating validity. It identified a principal factor, explaining 67% of the variance. CONCLUSIONS: The IES-R can be used in the Chilean population to assess the degree of suffering produced by a traumatic event.

At least two expressed genes for transcription factors Pitx2 and Rpx are present in common carp and are upregulated during winter acclimatization.

The mechanisms of seasonal acclimatization in eurythermal fish such as common carp are not fully understood. Here, we concentrate on the regulation of pituitary factors, as this organ was shown to be highly affected by seasonal changes. We cloned and sequenced two different cDNAs for each of the transcription factors Pitx2 and Rpx, known to play a role in pituitary development. We show that these genes are conserved throughout evolution, to different degrees depending on the specific domain considered. Finally, we show that the cDNAs for both factors are clearly up-regulated during the winter season, in sharp contrast to other regulators such as Pit1 or pituitary hormone genes such as prolactin (prl) and growth hormone (gh). Our results suggest that increased expression of Pitx2 and Rpx contributes to seasonal adaptation of common carp to winter conditions.

Tratamiento y evolución de la encefalitis inmunomediada en edad pediátrica, serie de casos / Treatment and outcome of immune-mediated encephalitis in children, a case series

Introducción: La encefalitis por anticuerpos contra el receptor N-metil.D.aspartato (NMDA-R) es un trastorno inflamatorio del sistema nervioso central (SNC) en el cual autoanticuerpos dirigidos hacia la subunidad NR1 del receptor N-metil-D aspartato (NMDA) desarrollan un conjunto de síntomas neuropsiquiátricos, convulsiones y movimientos anormales. El tratamiento recomendado incluye metilprednisolona (MP) y gamaglobulina (IVIg), y/o recambio plasmático terapéutico (RPT); y en caso de no respuesta: rituximab (RTX) y/o ciclofosfamida (CFM). Objetivos: Analizar características clínicas, bioquímicas, electroencefalograma (EEG), resonancia magnética (RM) cerebral, tratamientos recibidos y resultados observados en una serie de pacientes con encefalitis autoinmune (EA) probable o confirmada. Materiales y métodos: Analizamos las historias clínicas de pacientes menores a 17 años que cumplían criterios diagnósticos de Graus (2016) para EA probable, con seguimiento mayor a 6 meses, internados en el Hospital Garrahan entre 2008 y 2023. El diagnóstico se definió por la identificación de anticuerpos anti-NMDAR (N-metil D-aspartato) en líquido cefalorraquídeo (LCR) por ensayo basado en células - cell bassed assay (CBA). Resultados: Reunieron criterios de EA probable 94 pacientes con una edad media de 89.5 meses, 51% mujeres. Se dividieron en dos grupos: seropositivos y seronegativos de acuerdo al resultado del biomarcador. Seropositivos 45/94. El síntoma inicial más frecuente fue: convulsiones. El 28% requirió ingreso a Unidad de Cuidados Intensivos (UCI). 4 pacientes seropositivos y 1 seronegativo tuvieron encefalitis por el virus del herpes simple (Om) previamente. En una paciente seronegativa se diagnosticó teratoma ovárico. Hallazgos de estudios complementarios: LCR patológico en el 29%, RM cerebral en el 52%, EEG en el 74%. El tratamiento de primera línea más empleado fue MP + IVIg. El 46% de los pacientes presentó recuperación completa. Entre los pacientes que recibieron RTX, el 65% tuvo una recuperación completa. Ningún paciente que recibió RTX presentó recaída. Conclusión: Ante la sospecha de EA se debe considerar el inicio temprano de inmunoterapia para favorecer la rápida recuperación funcional. Se recomienda el uso temprano de RTX en los casos con presentación grave o respuesta subóptima al tratamiento de primera línea para beneficiar la respuesta clínica y reducir el riesgo de recaída (AU)

Introduction: Encephalitis due to antibodies against the N-methyl-D-aspartate receptor (NMDA-R) is an inflammatory disorder of the central nervous system (CNS) in which autoantibodies directed against the NR1 subunit of the N-methyl-D-aspartate (NMDA) receptor develop a set of neuropsychiatric symptoms, seizures, and abnormal movements. The recommended treatment includes methylprednisolone (MP) and intravenous immunoglobulin (IVIg), and/or therapeutic plasma exchange (TPE); and in case of non-response: rituximab (RTX) and/or cyclophosphamide (CFM). Objectives: To analyze clinical, biochemical, electroencephalogram (EEG), magnetic resonance imaging (MRI) of the brain, treatments received, and outcomes observed in a series of patients with probable or confirmed autoimmune encephalitis (AE). Materials and methods: We analyzed the medical records of patients under 17 years of age who met Graus' diagnostic criteria (2016) for probable AE, with follow-up of more than 6 months, hospitalized at Hospital Garrahan between 2008 and 2023. Diagnosis was defined by the identification of anti-NMDAR antibodies (N-methyl D-aspartate) in cerebrospinal fluid (CSF) by cell-based assay (CBA). Results: Ninety-four patients met criteria for probable AE with a mean age of 89.5 months, 51% female. They were divided into two groups: seropositive and seronegative according to the biomarker result. Seropositive 45/94. The most frequent initial symptom was seizures. Twenty-eight percent required admission to the Intensive Care Unit (ICU). Four seropositive patients and one seronegative patient had previously had herpes simplex encephalitis (Om). Ovarian teratoma was diagnosed in one seronegative patient. Findings of complementary studies: Pathological CSF in 29%, brain MRI in 52%, EEG in 74%. The most commonly used first-line treatment was MP + IVIg. Forty-six percent of patients experienced complete recovery. Among patients who received RTX, 65% had complete recovery. No patient who received RTX experienced relapse. Conclusion: In the suspicion of AE, early initiation of immunotherapy should be considered to promote rapid functional recovery. Early use of RTX is recommended in cases with severe presentation or suboptimal response to first-line treatment to benefit clinical response and reduce the risk of relapse (AU)

Clock gene expression in adult primate suprachiasmatic nuclei and adrenal: is the adrenal a peripheral clock responsive to melatonin?

The circadian production of glucocorticoids involves the concerted action of several factors that eventually allow an adequate adaptation to the environment. Circadian rhythms are controlled by the circadian timing system that comprises peripheral oscillators and a central rhythm generator located in the suprachiasmatic nucleus (SCN) of the hypothalamus, driven by the self-regulatory interaction of a set of proteins encoded by genes named clock genes. Here we describe the phase relationship between the SCN and adrenal gland for the expression of selected core clock transcripts (Per-2, Bmal-1) in the adult capuchin monkey, a New World, diurnal nonhuman primate. In the SCN we found a higher expression of Bmal-1 during the h of darkness (2000-0200 h) and Per-2 during daytime h (1400 h). The adrenal gland expressed clock genes in oscillatory fashion, with higher values for Bmal-1 during the day (1400-2000 h), whereas Per-2 was higher at nighttime (about 0200 h), resulting in a 9- to 12-h antiphase pattern. In the adrenal gland, the oscillation of clock genes was accompanied by rhythmic expression of a functional output, the steroidogenic enzyme 3beta-hydroxysteroid dehydrogenase. Furthermore, we show that adrenal explants maintained oscillatory expression of Per-2 and Bmal-1 for at least 36 h in culture. The acrophase of both transcripts, but not its overall expression along the incubation, was blunted by 100 nm melatonin. Altogether, these results demonstrate oscillation of clock genes in the SCN and adrenal gland of a diurnal primate and support an oscillation of clock genes in the adrenal gland that may be modulated by the neurohormone melatonin.

First Report of Pantoea agglomerans Causing Leaf Blight and Vascular Wilt in Maize and Sorghum in Mexico.

Zea mays and Sorghum bicolor are important crops for animal and human nutrition worldwide. In the Central Highland Valley of Mexico, both crops are extremely important, and research is aimed toward increasing yield, disease resistance, and crop adaptation from 1,900- to 2,700-m elevation. In a 3-year field breeding experiment (2004 to 2006), leaf blight and vascular wilt symptoms were frequently observed in contiguous plots of maize and sorghum crops in Montecillo, Mexico and maize plots in Tecamac, Mexico. To identify and characterize the causal agent of these symptoms, isolations were conducted on leaves from areas where healthy and diseased tissues converged. Leaf sections of 1 cm2 from both crops were disinfested, placed on casamino acid-peptone-glucose (CPG) medium, and incubated at 28°C. After 48 h, only yellow colonies were observed and 12 isolates were selected for further characterization. Physiological and biochemical tests indicated that the isolates were nonfluorescent on King's B medium, and API 50 CHE (bioMérieux, Marcy l'Etoile, France) revealed that they were negative for gelatin hydrolysis, indole production, acid production from raffinose and positive for utilization of glycerol, D-glucose, mannitol, arbutine, esculine, salicine, cellobiose, maltose, melibiose, D-fucose, and D-arabitol; all characteristics of Pantoea agglomerans. Further identification of these isolates was accomplished by DNA analysis. For DNA analysis, 1.4-kbp fragments of the 16S rRNA gene were amplified with primer set 8F/1492R (3) and sequenced with U514F/800R universal primers (2). Five sequences were obtained and deposited in GenBank (Accession Nos. EF050806 to EF050810). A phylogenetic tree was constructed using the UPGMA method (mega version 3.1). Results of the phylogenetic analysis grouped the species P. ananatis, P. stewartti, and P. agglomerans into three clusters. The five unknown sequences were grouped into the P. agglomerans cluster. There was a 98 to 99% similarity of the five 16S rRNA gene sequences with P. agglomerans strain type ATCC 27155. Pathogenicity of the 12 isolates was confirmed by injecting 108 CFU mL-1 of inoculum into stems of 3-week-old maize cv. Triunfo and sorghum cold tolerant hybrid (A1×B5)×R1 seedlings in the greenhouse at 28°C and 80% relative humidity. Also, seedlings were inoculated with water, nonpathogenic isolates of P. agglomerans from maize (GM13, and HLA1), and not inoculated as negative controls. Three replications were included for each isolate and control. All test strains developed water-soaked lesions on juvenile leaves at 8 days postinoculation and were followed by chlorotic to straw-colored leaf streaks and then leaf blight symptoms at 3 weeks postinoculation. All negative control seedlings did not develop symptoms. In addition, the 12 isolates were infiltrated at 107 CFU mL-1 into tobacco leaves that displayed a hypersensitive response at 4 days, indicating the presence of the type III secretion system (1). Isolates were reisolated, and the 16S rRNA gene fragments were 100% similar to their original isolate sequences. P. agglomerans has been reported to affect other crops, including chinese taro in Brazil (2007), onion in the United States (2006) and South Africa (1981), and pearl millet in Zimbabwe (1997); however, to our knowledge, this is the first report of P. agglomerans associated with leaf blight and vascular wilt symptoms in maize and sorghum in the Central Highland Valley of Mexico. References: (1) J. Alfano and A. Collmer. Annu. Rev. Phytopathol 42:385, 2004. (2) Y. Anzai et al. Int. J. Syst. Evol. Microbiol. 50:1563, 2000. (3) M. Sasoh et al. Appl. Environ. Microbiol. 72:1825, 2006.

Uso del cannabis medicinal en niños con encefalopatías epilépticas farmacorresistentes. Experiencia en Hospital Garrahan / Use of medicinal cannabis in children with drug-resistant epileptic encephalopathies. Experience at Garrahan Hospital

Objetivo: Reportamos resultados sobre la efectividad, seguridad y tolerancia del cannabidiol como adyuvante terapéutico en pacientes pediátricos con encefalopatías epilépticas del desarrollo (EED) resistentes al tratamiento farmacológico y no farmacológico tras un seguimiento promedio de 20 meses. Métodos: Se realizó un estudio de cohorte prospectivo para evaluar la eficacia, la seguridad y la tolerancia del aceite de cannabis medicinal enriquecido con CBD añadido a los medicamentos anticonvulsivos estándar en niños con EED resistentes a los medicamentos atendidos en un único centro. Resultados: Entre octubre de 2018 y marzo de 2020, se incluyeron 59 pacientes. La edad media en el momento del inicio del protocolo fue de 10,5 años (rango, 2-17 años). La mediana de la duración del tratamiento fue de 20 meses (rango, 12-32). La mediana de edad en el momento de la primera convulsión fue de 8 meses (rango, 1 día - 10 años). Al final del seguimiento, el 78% de los niños tenía una disminución ≥ 50% en frecuencia de las crisis y el 47,5% tenía una disminución > 75%. Siete pacientes (11,9%) estaban libres de convulsiones. El número de crisis se redujo de una mediana de 305/mes a 90/mes, que supone una reducción media del 57% y una mediana del 71% (p < 0,0001). Los efectos adversos fueron en su mayoría leves o moderados. El CBD se interrumpió en 17 pacientes (28,8%) por falta de respuesta al tratamiento, aumento de la frecuencia de las convulsiones, intolerancia al fármaco o cumplimiento terapéutico insuficiente. Conclusión: En los niños con EED resistentes a los fármacos, el tratamiento a largo plazo del cannabis medicinal enriquecido con CBD como terapia adyuvante resultó ser seguro, bien tolerado y eficaz. Las reducciones sostenidas en la frecuencia de las convulsiones y la mejora de los aspectos de la vida diaria se observaron en comparación con nuestros preliminares (AU)

Objective: We report results on the effectiveness, safety, and tolerance of cannabidiol (CBD) as add-on therapy in children with developmental and epileptic encephalopathies (DEE) resistant to pharmacological and non-pharmacological treatment after a mean follow-up of 20 months. Methods: A prospective cohort study was conducted to evaluate the efficacy, safety, and tolerability of CBD-enriched medical cannabis oil added to standard antiseizure medications in children with drug-resistant DEEs seen at a single center. Results: Between October 2018 and March 2020, 59 patients were included. The median age at protocol initiation was 10.5 years (range, 2-17 years). Median treatment duration was 20 months (range, 12-32). The median age at the time of the first seizure was 8 months (range, 1 day - 10 years). At the end of follow-up, 78% of the children had a decrease ≥ 50% in seizure frequency and 47.5% had a decrease of > 75%. Seven patients (11.9%) were seizure free. The number of seizures was reduced from a median of 305/month to 90/month, accounting for a mean reduction of 57% and a median of 71% (p < 0.0001). Adverse effects were mostly mild or moderate. CBD was discontinued in 17 patients (28.8%) due to lack of response to treatment, increased seizure frequency, drug intolerance, or poor compliance. Conclusion: In children with drug-resistant DEE, long-term treatment with CBD-enriched medicinal cannabis as add-on therapy proved to be safe, well tolerated, and effective. Sustained reductions in seizure frequency and improvement in aspects of daily living were observed compared to our preliminary results (AU)

Maternal melatonin effects on clock gene expression in a nonhuman primate fetus.

In the adult mammal the circadian system, which allows predictive adaptation to daily environmental changes, comprises peripheral oscillators in most tissues, commanded by the suprachiasmatic nucleus (SCN) of the hypothalamus. The external environment of the fetus is provided by its mother. In primates, maternal melatonin is a candidate to entrain fetal circadian rhythms, including the SCN rhythms of metabolic activity. We found in the 90% of gestation capuchin monkey fetus expression of the clock genes Bmal-1, Per-2, Cry-2, and Clock in the SCN, adrenal, pituitary, brown fat, and pineal. Bmal-1, Per-2, and the melatonin 1 receptor (MT1) showed a robust oscillatory expression in SCN and adrenal gland, whereas a circadian rhythm of dehydroepiandrosterone sulphate was found in plasma. Maternal melatonin suppression changed the expression of Bmal-1, Per-2, and MT1 in the fetal SCN. These effects were reversed by maternal melatonin replacement. In contrast, neither maternal melatonin suppression nor its replacement had effects on the expression of Per-2 and Bmal-1 or MT1 in the fetal adrenal gland or the circadian rhythm of fetal plasma dehydroepiandrosterone sulphate. Our data suggest that maternal melatonin is a Zeitgeber for the fetal SCN but probably not for the adrenal gland.

Esophageal perforation. A reassessment of the criteria for choosing medical or surgical therapy.

Treatment for esophageal perforation has traditionally been surgery, but development of more effective antibiotics and parenteral nutrition has led to a cautious trend toward nonoperative management. The goal of this investigation was to identify relevant presenting features that would guide a physician in making the therapeutic choice between medical and surgical therapy. Twenty-five consecutive patients with esophageal perforation--20 iatrogenic and five spontaneous--were reviewed. Treatment was medical in 12 cases and surgical in 13. The findings indicate that many patients with esophageal perforation can be treated medically. The following guidelines are suggested for selecting nonoperative treatment: (1) clinically stable patients; (2) instrumental perforations detected before major mediastinal contamination has occurred or perforations with such a long delay in diagnosis that the patient has already demonstrated tolerance for the perforation without the need for surgery; and (3) esophageal disruptions well contained within the mediastinum or a pleural loculus.

Effect of constant light on fetal and maternal prolactin rhythms in sheep.

A 24-h rhythm of plasma PRL is present in fetal sheep. This rhythm is synchronized to an environmental clue (zeitgeber). We determined whether the light-dark cycle (L:D) is a zeitgeber for the fetal PRL rhythm and, if so, whether the mother might convey this zeitgeber to the fetus. We kept nine ewes (twin pregnancies) in constant light (L:L) and five ewes (singleton) in 14:10 L:D from 110 days gestation. Fetuses and mothers were catheterized at 119 days gestation. Blood samples were taken hourly for 24 h after 16 days under L:L or L:D. A mean 24-h rhythm of PRL was found (by RIA) in fetuses under L:D, but not in those under L:L. However, fetuses under L:L showed individual 24-h PRL rhythms (cosinor analysis) whose acrophases were distributed around the clock. Nonsynchronized rhythms persisted after 23 and 30 days of L:L. Acrophases of PRL rhythms within a set of twins were closer than those between sets, suggesting that twins were responding to a common signal. These findings indicate that the L:D cycle is a zeitgeber for the PRL rhythm in fetal sheep and suggest that the mother might convey the zeitgeber.

Prenatal development of the retinohypothalamic pathway and the suprachiasmatic nucleus in the sheep.

Circadian rhythms are present during fetal life in several mammalian species. To characterize the ontogeny of the neural mechanisms that account for circadian rhythmicity in a precocious species, we studied the prenatal development of the retinohypothalamic pathway in lambs (gestation period of 147 days), using horseradish peroxidase and wheat germ agglutinin as anterograde tracers. The suprachiasmatic nucleus was present as early as embryonic day 52 (E52). After E58, the suprachiasmatic nucleus reached its full number of neurons, estimated by the disector method in about 160,000 cells per nucleus at E62. The retinohypothalamic axons invaded the suprachiasmatic nucleus from E58, while neuroblasts were still migrating to the nucleus. At E62, there was a strong retinal projection that evolved until E121, when the retinal afferents established their definitive pattern of distribution in the ventral and central regions of the suprachiasmatic nucleus, and adjacent hypothalamic structures. The development of the retinohypothalamic pathway was delayed by about a week relative to the innervation of other subcortical visual centers. The present findings demonstrated an early prenatal development of the visual pathways in lambs, including the retinohypothalamic pathway, suggesting that the mechanisms for the visual entrainment of circadian rhythms in lambs may be functioning several weeks before birth.

A noninvasive scintigraphic assessment of the colonic transit of nondigestible solids in man.

A noninvasive, scintigraphic technique for quantifying large intestinal transit time that provides low radiation doses was developed. The scintigraphic large intestinal transit (SLIT) method uses a total of 100 microCi of 111In encapsulated in ten 2-cm nondigestible capsules, which are ingested after a 6-hr fast. Two hundred fifty microcuries of 99mTc-sulfur colloid were given to outline the gastrointestinal tract. Images were acquired at 4-hr intervals until all capsules were excreted. Normal volunteers (n = 10) consumed a standardized diet 2 days prior and during imaging. Segmental transit times were measured in the following: ascending, transverse, descending, recto-sigmoid colons; hepatic and splenic flexures. The radiation absorbed dose to the large intestine for the SLIT technique is less than half of that associated with other radiographic methods of colonic transit time measurement.

Transdermal scopolamine as treatment of bradyarrhythmias.

Fifteen patients with different degrees of chronic bradyarrhythmias of supraventricular origin were studied with Holter monitoring before and during application of a transdermal patch of scopolamine. No changes were found in the mean or minimal heart rates, standard deviation of the RR interval, or the degree of bradyarrhythmia. It is concluded that transdermal scopolamine is not an adequate treatment of chronic symptomatic bradyarrhythmias.

Use of magnesium sulfate to treat hyperstimulation in term labor.

Magnesium sulfate has been shown in vivo and in vitro to decrease the frequency of uterine contractions while maintaining the amplitude; we therefore decided to assess the use of magnesium sulfate infusion in cases of uterine hyperstimulation. The medical records were reviewed retrospectively for 37 term pregnant patients diagnosed as having uterine hyperstimulation during labor. None of them had medical or obstetric complications. Twenty-two of them received oxytocin augmentation for abnormal labor. Although the vast majority of these patients had a decrease of the hyperstimulation while being given the magnesium, 31.8% in the group receiving oxytocin alone (P less than .05). Fifteen additional patients received magnesium sulfate for uterine hyperstimulation although they were not receiving oxytocin; of these, 16.7% required cesarean delivery. This rate was no different from that of the patients who required labor augmentation, but was double the overall primary cesarean rate at our hospital. There appears to be a group of patients with abnormal uterine activity (either spontaneous or associated with oxytocin augmentation) that responds to treatment with magnesium sulfate.