Effect of breathing motion on robustness of proton therapy plans for left-sided breast cancer patients with indication for locoregional irradiation.

PURPOSE: To investigate the dosimetric impact of breathing motion on robustly optimized proton therapy treatment plans for left-sided breast cancer patients with an indication for locoregional irradiation. MATERIALS AND METHODS: Clinical Target Volumes (CTVs) (left-sided breast, level 1 to 4 axillary lymph nodes, interpectoral and internal mammary lymph node regions) and organs at risk were delineated on 4 D-CTs of ten female patients. After treatment planning to a prescribed dose of 40.05 Gy(RBE) in 15 fractions on the time-averaged CT, the dose was calculated on all ten phases of the breathing cycle. Robustness to setup (5 mm) and range errors (3%) was evaluated for those ten phases. Correlations were evaluated between the phases of the breathing cycle and the D98% of the CTV and the Dmean of the heart. RESULTS: Correlations coefficients were between -0.12 and 0.29. At the most extreme values of the 28 robustness scenarios, the clinical goals were met for all but two patients. The mean heart dose was 0.41 Gy(RBE) with a standard deviation of 0.31 Gy(RBE) of proton therapy plans. CONCLUSION: The effect of breathing motion on the robustness of proton therapy treatment plans for this patient group is minor and not of clinical significance. Based on this patient group, a deep-inspiration breath hold seems to be unnecessary to improve robustness for these patients.

An Alternative Splice Variant of Zebrafish Cx52.6 is Expressed in Retinal Horizontal Cells.

Retinal horizontal cells (HCs) are inhibitory neurons, which modulate the transmission of light-elicited signals from photoreceptors to bipolar cells in the outer retina. HCs of the same physiological type are extensively coupled via gap junctions. In the zebrafish retina, the population of HCs comprises up to four morphologically distinct subtypes. Four different connexins (Cx52.6, Cx52.7, Cx52.9 and Cx55.5) were detected in these cells with overlapping expression patterns. In this study, we show that Cx52.6 is alternatively spliced in the retina, resulting in an additional isoform, designated as Cx53.4, which differs from the originally described Cx52.6 only by the final C-terminal peptide (12 vs. 4 aa). Further protein sequence alignments revealed that Cx53.4 represents the counterpart of alternatively spliced mouse Cx57 and human Cx62. RT-PCR analyses of mRNA expression in different adult zebrafish tissues showed that Cx53.4 is expressed exclusively in the retina. The localization of Cx53.4 protein within the retina was analyzed using a specific antibody. Immunofluorescence analyses demonstrated that the expression of Cx53.4 is restricted to HCs of all four subtypes. Further, immunoelectron microscopy confirmed the presence of Cx53.4 in gap junctions between HC dendrites and between their axon terminals.

[Outcome of surgery for Crohn's colitis. Review of 28 cases]. / Colitis de Crohn: resultados del tratamiento quirúrgico y evolución alejada.

BACKGROUND: Exclusive involvement of the colon or rectum in Crohn's disease, called Crohn's colitis, (CC) occurs in about 25% of these patients. AIM: To analyze early surgical results and long-term outcomes of patients undergoing surgery for CC. MATERIAL AND METHODS: Review of a prospective database, identifying patients with Crohn's disease operated between 2003 and 2015 and excluding those with ileocecal disease. We analyzed demographic data, pre and postoperative pharmacological treatment, operations, morbidity and the need for a second bowel resection at follow-up. RESULTS: We reviewed data from 28 patients aged 17 to 72 years (15 men). Twenty-seven (96.4%) had previous pharmacological treatment, 11 received monoclonal antibodies. The most common indications for surgical treatment were failure of medical treatment in 15 cases, acute severe colitis in 12 and anemia/malnutrition in eight. Total colectomy was performed in 17 (61%) patients, proctocolectomy in 8 (29%) and segmental colectomies in 3 (11%). Sixteen (57%) were operated laparoscopically. Major postoperative complications were observed in 5 (18%). Four needed a reintervention. There was no operative mortality. During a 55 months median follow-up of 27 patients, seven (26%) required a second bowel resection, one of them for recurrence. Nineteen (70%) patients had an ostomy, which was permanent in 11. Fifteen patients are without medical treatment. CONCLUSIONS: Most of the reviewed patients required total colectomy for the control of the disease with a low surgical morbidity. Two-thirds required an ileostomy, which became permanent in half of them.

Colitis de Crohn: resultados del tratamiento quirúrgico y evolución alejada / Outcome of surgery for Crohn's colitis: review of 28 cases

Background: Exclusive involvement of the colon or rectum in Crohn's disease, called Crohn's colitis, (CC) occurs in about 25% of these patients. Aim: To analyze early surgical results and long-term outcomes of patients undergoing surgery for CC. Material and Methods: Review of a prospective database, identifying patients with Crohn's disease operated between 2003 and 2015 and excluding those with ileocecal disease. We analyzed demographic data, pre and postoperative pharmacological treatment, operations, morbidity and the need for a second bowel resection at follow-up. Results: We reviewed data from 28 patients aged 17 to 72 years (15 men). Twenty-seven (96.4%) had previous pharmacological treatment, 11 received monoclonal antibodies. The most common indications for surgical treatment were failure of medical treatment in 15 cases, acute severe colitis in 12 and anemia/malnutrition in eight. Total colectomy was performed in 17 (61%) patients, proctocolectomy in 8 (29%) and segmental colectomies in 3 (11%). Sixteen (57%) were operated laparoscopically. Major postoperative complications were observed in 5 (18%). Four needed a reintervention. There was no operative mortality. During a 55 months median follow-up of 27 patients, seven (26%) required a second bowel resection, one of them for recurrence. Nineteen (70%) patients had an ostomy, which was permanent in 11. Fifteen patients are without medical treatment. Conclusions: Most of the reviewed patients required total colectomy for the control of the disease with a low surgical morbidity. Two-thirds required an ileostomy, which became permanent in half of them.

Nuevas emulsiones lipídicas enriquecidas con omega-3: beneficios reales en nutrición parenteral / New lipid emulsions enriched with omega-3: Is there a real benefit on parenteral nutrition?

Total parenteral nutrition allows nutritional supports for patients who are not able to receive oral intake or enteral nutrition. Fatty acids are administrated as lipid emulsions and a lower inflammatory cytokine level has been described after administration of Omega-3. This could be a benefit for critical patients by a potential antiinflamatory and immunomodulation effect. Also, for patients with respiratory distress syndrome, the lower cytokine effect may directly affect pulmonary vessels by vasodilatation and consequently improve respiratory function. Different studies have shown positive clinical outcomes after Omega-3 administration, while other studies have failed to demonstrate significant results. Mechanisms involved with this possible immunomodulation by fish oil are well known, although further research is necessary to clarify the clinical relevance of these mechanisms.

La nutrición parenteral es la técnica de soporte nutricional por vía endovenosa a pacientes que no pueden alimentarse por vía enteral u oral. El aporte de lípidos se realiza a través de emulsiones lipídicas, que poseen diferentes ácidos grasos. Se ha descrito que la administración de ácidos grasos Omega-3 determina una disminución de citoquinas proinflamatorias a nivel plasmático, lo cual supondría beneficios en los pacientes críticos mediante una posible modulación de la respuesta inflamatoria e inmunológica. Además, en los pacientes con distress respiratorio agudo, la disminución de citoquinas proinflamatorias ejercería un efecto directo sobre el lecho vascular pulmonar estableciendo una mejoría de la función respiratoria. Los estudios clínicos son contradictorios respecto a si la suplementación con Omega-3 se asocia con resultados clínicos favorables en forma significativa. Existe gran avance en el conocimiento de los mecanismos involucrados en la posible inmunomodulación que se le atribuye al aceite de pescado, pero futuras investigaciones son necesarias para elucidar la relevancia clínica de estos mecanismos.

[Serial transverse enteroplasty for short bowel syndrome. Case report]. / Enteroplastía transversa seriada como alternativa en el tratamiento del síndrome de intestino corto. Caso clínico.

Among patients with short bowel syndrome, surgical small intestine lengthening techniques are employed to increase the absorptive surface. Among these, serial transverse enteroplasty involves transecting the bowel transversally, preserving the blood supply of the small intestine and creating a longer segment of bowel. We report a 51-year-old woman with a short bowel syndrome and multiple hospital admissions for complications. She was subjected to a serial transverse enteroplasty, increasing small intestinal length from 140 to 180 cm. During the postoperative period, she presented intra abdominal blood collections and a septic episode with bacterial endocarditis. One month after the operation, total parenteral nutrition was discontinued and nutritional and fluid balances were achieved using exclusively the oral route. During the ambulatory follow up, the patient continues with exclusive oral feeding and five bowel movements per day.

Enteroplastía transversa seriada como alternativa en el tratamiento del síndrome de intestino corto: caso clínico / Serial transverse enteroplasty for short bowel syndrome: case report

Among patients with short bowel syndrome, surgical small intestine lengthening techniques are employed to increase the absorptive surface. Among these, serial transverse enteroplasty involves transecting the bowel transversally, preserving the blood supply of the small intestine and creating a longer segment of bowel. We report a 51-year-old woman with a short bowel syndrome and multiple hospital admissions for complications. She was subjected to a serial transverse enteroplasty, increasing small intestinal length from 140 to 180 cm. During the postoperative period, she presented intra abdominal blood collections and a septic episode with bacterial endocarditis. One month after the operation, total parenteral nutrition was discontinued and nutritional and fuid balances were achieved using exclusively the oral route. During the ambulatory follow up, the patient continues with exclusive oral feeding and fve bowel movements per day.

Propuesta y fundamentos para una norma de manejo quirúrgico del paciente obeso: Año 2004 / A proposal of guidelines for surgical management of obesity

Obesity is a chronic disease with an increasing prevalence in all groups of age, and is associated to increased general mortality and cardiovascular risk. The multidisciplinary non surgical approach must be the treatment of choice for obese subjects. However, the results of such approach among subjects with severe or morbid obesity, are unsatisfactory. In this group of patients, bariatric surgery and specifically gastric bypass achieves good long term results, maintaining a low body mass index, reducing complications and improving quality of life. Considering the widespread practice of bariatric surgery in Chile, the Nutrition Unit of the Ministry of Health formed a task force to propose update guidelines for the surgical treatment of obesity. These guidelines were proposed after a thorough literature review and discussion with groups that practice bariatric surgery using defined protocols. This document provides a summarized version of the guidelines. The first section discusses the background for bariatric surgery and the second part give specific recommendations for patient management and the formation of reference centers for surgical management of obesity.

Recovery of neuroendocrine cells after injury in the aging brain of a mollusc.

Recovery after crush of neuroendocrine caudodorsal cells (CDCs) in the aging brain of the mollusc Lymnaea stagnalis, was determined as a measure of neuronal plasticity. Neuronal plasticity was determined in differently aged animals containing intact (young: 170 days) or morphologically and physiologically degraded (middle-aged: 305 days and old: 443 days) CDCs. Branching patterns and electrical and chemical connectivity and afterdischarge activity of CDCs were studied. Immediately after crush, electrical coupling and chemical transmission were absent. In all age groups partial recovery occurred within about 20 days. CDCs in old animals exhibited restricted recovery of electrical coupling and enhanced recovery of chemical transmission. In young and middle-aged animals normal afterdischarges occurred from day 8 on. In old animals abnormal afterdischarges occurred starting at day 0, becoming normal by day 12 after crush. Recovery of CDC branching was partial in all age groups. It is concluded that in the aging brain recovery of CDCs after injury does occur but is differentially restricted. Our results suggest that senescent degraded neurons still possess a considerable degree of plasticity.

Mecanismos de contaminación de las fórmulas para nutrición enteral / Mechanisms of contamination of formulas for enteral nutrition

Una de las complicaciones más frecuentes de la nutrición enteral es la contaminación de las fórmulas. El objetivo de este trabajo fue evaluar la frecuencia y los mecanismo por los cuales se produce la contaminación en las fórmulas enterales. Se evaluaron dos tipos de fórmulas, una en polvo y la otra líquida estéril, con contenedores reutilizados y estériles. Los resultados demuestran que el mecanismo más importante de contaminación se produce en la central de fórmulas por la manipulación o por el uso de utensilios contaminados. La utilización de contenedores reutilizados contribuye a la contaminación, pero en un menor grado. Las bajadas de los contenedores tienen altos porcentajes de contaminación, superiores al 85 por ciento y no se modifican con el uso de material estéril. Probablemente exista también un mecanismo de contaminación retrógrado

Multiple synaptic connections of a single neuron change differentially with age.

The efficacy of chemical synaptic connections of a single identified interneuron with different types of follower neurons was studied throughout the adult life of the pond snail Lymnaea stagnalis. Simultaneous intracellular recordings were made from the interneuron RPeD1 and its follower neurons in isolated CNS preparations from animals of different age groups (3-18 months of age). The presence of postsynaptic responses to RPeD1 action potentials was tested. With increasing age, the number of A-group neurons that was found with a response to evoked RPeD1 action potentials decreased, yet the number of HIJK-group neurons responding to RPeD1 input increased. The number of G-group neurons and the number of individual neurons VD2/3 and VD4 with RPeD1 input did not differ significantly between age groups. However, there was variability in the presence of responses in these individual neurons. Thus, synaptic connections of the single interneuron RPeD1 change differentially throughout the adult life of L. stagnalis. Within the A-group we found indications that changes in RPeD1 input apply to the entire A-group. In the A-group neurons changes in several electrical properties could not account for the observed age-related changes in the number of neurons responding to RPeD1 action potentials.

Nutrición enteral en crisis grave de colitis ulcerosa: efectividad nutricional y tolerancia digestiva / Enteral nutrition in severe ulcerative colitis: safety, tolerance and nutritional efficiency

Backgrounds and aims: Total parenteral nutrition (TPN) has been traditionally used as an adjunctive therapy in severe ulcerative colitis patients. We performed a prospective study to ascertain the safety, nutritional efficiency, tolerance and costs of total enteral nutrition in this situation. Methods: After 48 hours of intensive medical treatment, severe ulcerative colitis patients initiated enteral feeding with a polymeric formula. The formula concentration and volume were increased daily. Results: 17 patients (7 women, 10 men; age 36,8ñ12,8 years) with a mean clinical activity score of 15,6ñ1,5 were included. In 14 patients (82,4percent) enteral nutrition was well tolerated, attaining in 11 of them more than 80percent of the caloric requirements by day 4. In 3 cases we observed vomiting and bloating. Prealbumin levels improved significantly from 11,1ñ3,4 mg/dl to 22,7ñ6,8 mg/dl (p= 0.002) at the end of enteral nutrition (11,8ñ4,7 days). Albumin and other nutritional parameters did not change. Conclusions: Total enteral nutrition could be considered a safe and well tolerated nutritional support in these patients. Although albumin and other nutritional parameters did not change during the study period, the increase in prealbumin levels suggests a favourable anabolic effect of total enteral nutrition

Metamorphic control of cyclic guanosine monophosphate expression in the nervous system of the tobacco hornworm, Manduca sexta.

During metamorphosis of Manduca sexta, defined sets of neurons show a dramatic accumulation of cyclic guanosine monophosphate (cGMP). Although many of these cells show low but detectable levels of cGMP during specific developmental windows, these levels are enhanced dramatically during dissection of the central nervous system (CNS). The ability of these neurons to show this induced cGMP expression depends on the developmental stage. Larvae do not show this capacity but it appears during the transition from the larval to the pupal stage. There are two different classes of response: the early expressing neurons start to show a cGMP response at the beginning of the prepupal stage while the late expressing cGMP neurons start at different times during the pupal-adult transition. The former set includes larval neurons that will likely be remodeled during metamorphosis, and a number of them are serotonergic. The late-expressing group also includes some larval cells, but most are adult-specific neurons. At least for one adult-specific cluster, the antennal lobe neurons, the cGMP expression parallels the maturation phase of these cells.

Déficit de hormona de crecimiento en pacientes con insuficiencia cardíaca crónica / Growth hormone deficiency in patients with chronic cardiac failure

Nine patients, aged 49 to 76 years old, 7 male, were studied. Seven had an idiopathic dilated cardiomyopathy and 2 a coronary heart disease. All had a stable cardiac failure, in functional capacity II or III and were receiving digoxin, furosemide and potassium supplements. Thyroid hormone levels, basal and exercise growth hormone and IGF-1 levels were measured and compared with reference values for American populations. Left ventricular ejection fraction was measured with an isotopic technique and nutritional status using anthropometry and indirect calorimetry. Anthropometric measures, basal and postprandial oxygen consumption were within normal limits. Thyroid hormone levels were normal. During maximal exercise, growth hormone levels were 2.56ñ4.1 ng/ml and IGF-1 levels were 0.56ñ0.61 mU/ml. These values were significantly lower than expected for age and sex. These patients with chronic cardiac failure have lower than normal growth hormone and IGF-1 levels

Ciprofibrato: nueva terapia farmacológica en la hipertrigliceridemia / Ciprofibrate: a new pharmacologic agent for treatment of hypertriglyceridemia

En 16 hombres portadores de dislipidemia IIb, excluyendodiabéticos y otras patologías graves, evaluamos prospectivamente el efecto en colesterol total, colesterol LDL, colesterol HDL y triglicéridos del ciprofibrato. Después de cuatro semanas con régimen adecuado y sin hipolipemiantes, se les indicaron 100 mg/día en dosis única si mantenían colesterol total o triglicéridos superiores a 200 mg/dL. Se reevaluaron a los 30 y 60 días, duplicando la dosis de ciprofibrato si persistía el colesterol total o los triglicéridos mayores a 200 mg/dL. Con 100 mg de ciprofibrato observamos disminución significativa de colesterol total (promedio ñ D.S. 258 ñ 36 a 228 ñ 28 mg/dL, p<0,002); colesterol LDL (192 ñ 47 a 156 ñ 26 mg/dL, p<0,005); triglicéridos (219 ñ 89 a 142 ñ 50 mg/dL, p<0,001) y elevación de colesterol HDL (35 ñ 7 a 43 ñ 6 mg/dL, p<0,001). Al duplicar la dosis de ciprofibrato en 12 pacientes, no se observó un efecto mayor. Ningún pacinete presentó efctos adversos que pudieran ser atribuidos al medicamento

Effects of octopamine on miniature excitatory junction potentials from developing and adult moth muscle.

Intracellular recordings of excitatory junction potentials (EJPs) and miniature EJPs (MEJPs) were made from the dorsal longitudinal muscle of Manduca sexta to determine the sites of action of octopamine. MEJPs increased in amplitude and frequency as the moth developed during the 3 days before eclosion. DL-Octopamine (5 X 10(-6) M) increased the amplitude of excitatory junction potentials in both immature moths (one day before eclosion) and adults. Octopamine (10(-5) M) also increased the amplitude and frequency of MEJPs from immature animals (one and two days before eclosion) but had the opposite effect on adults and pharate adults ready to eclose. Treatment with octopamine (10(-5) M) resulted in a decrease in input resistance and a hyperpolarization in both immature and adult muscle fibers. The results suggest that octopamine acts both presynaptically and postsynaptically but that the increase in the amplitude of the evoked response is due primarily to influences on presynaptic processes.