Traditional potato tillage systems in the Peruvian Andes impact bacterial diversity, evenness, community composition, and functions in soil microbiomes.

The soil microbiome, a crucial component of agricultural ecosystems, plays a pivotal role in crop production and ecosystem functioning. However, its response to traditional tillage systems in potato cultivation in the Peruvian highlands is still far from understood. Here, ecological and functional aspects of the bacterial community were analyzed based on soil samples from two traditional tillage systems: 'chiwa' (minimal tillage) and 'barbecho' (full tillage), in the Huanuco region of the Peruvian central Andes. Similar soil bacterial community composition was shown for minimal tillage system, but it was heterogeneous for full tillage system. This soil bacterial community composition under full tillage system may be attributed to stochastic, and a more dynamic environment within this tillage system. 'Chiwa' and 'barbecho' soils harbored distinct bacterial genera into their communities, indicating their potential as bioindicators of traditional tillage effects. Functional analysis revealed common metabolic pathways in both tillage systems, with differences in anaerobic pathways in 'chiwa' and more diverse pathways in 'barbecho'. These findings open the possibilities to explore microbial bioindicators for minimal and full tillage systems, which are in relationship with healthy soil, and they can be used to propose adequate tillage systems for the sowing of potatoes in Peru.

Biomechanical Gait Effects of a Single Intervention with Wearable Closed Loop Control FES System in Chronic Stroke Patients. A Proof-of-Concept Pilot Study.

Foot drop is a gait disturbance characterized by difficulty in performing ankle dorsiflexion during the swing phase of the gait cycle. Current available evidence shows that functional electrical stimulation (FES) on the musculature responsible for dorsal ankle flexion during gait can have positive effects on walking ability. This study aims to present a proof of concept for a novel easy-to-use FES system and evaluates the biomechanical effects during gait in stroke patients, compared to unassisted walking. Gait was quantitatively evaluated in a movement analysis laboratory for five subjects with chronic stroke, in basal condition without assistance and in gait assisted with FES. Improvements were found in all temporospatial parameters during FES-assisted gait, evidenced by statistically significant differences only in gait speed (p=0.02). Joint kinematics showed positive changes in hip abduction and ankle dorsiflexion variables during the swing phase of the gait cycle. No significant differences were found in the Gait Deviation Index. In conclusion, the present pilot study demonstrates that the use of this FES system in the tibialis anterior muscle can cause gait functional improvements in subjects with foot drop due to chronic stroke.

Impact of chitosan based edible coatings functionalized with natural compounds on Colletotrichum fragariae development and the quality of strawberries.

The antifungal effect of chitosan edible coatings (ChEC) functionalized with cinnamon essential oil and aqueous extract of Roselle calyces on Colletotrichum fragariae growth and physical-chemical, physiological and nutraceutical features of strawberries at 5 and 20 °C were evaluated. ChEC was characterized with respect to its water vapor permeability (WVP) and mechanical properties. Results indicated that C. fragariae grew from the third day in strawberries stored at 20 °C, whilst at 5 °C disease symptoms were observed after 10 days in fruit inoculated and treated with ChEC after 24 h. The weight loss was reduced 15 times and firmness was higher by 33% in fruit treated with ChEC and stored at 5 °C. The antioxidant capacity of strawberries increased at the end of the storage only in control group. In conclusion, ChEC can be an effective technology for preserving quality strawberries for 17 days at 5 °C.

Ultrastructure of the anterior intestinal epithelia of the orange-spotted grouper Epinephelus coioides larvae under different feeding regimes.

Enterocytes of the anterior to midsection of the intestine in grouper Epinephelus coioides larvae were compared among different treatments: unfed to the point-of-no-return (PNR), fed natural food only, and co-fed natural food and artificial diet. On day 3, the nutritional condition of unfed grouper larvae regressed with its reduced enterocyte heights which were further degraded on day 4, the PNR, when all the enterocytes were in advanced stages of apoptosis. The apoptosis appeared to be internally directed via the mitochondria. Among day 3 fed larvae, enterocyte heights of those fed artificial diet did not differ from those fed natural food only. Dietary phospholipid deficiency was indicated in larvae co-fed artificial diet on day 3 with an unusually large chylomicron opening into the inter-enterocyte space, and on days 6 and 33 by intestinal steatosis. On day 19, scant to absent lipid droplets in enterocytes of larvae disclosed heightened nutritional requirement preparatory to metamorphosis. As observed in unfed day 3 and premetamorphic day 19 E. coioides, larvae undergoing critical periods and starvation during development employ apoptosis to dispose of degenerated enterocytes that are phagocytosed by adjacent healthy enterocytes without causing inflammatory distress. Upon metamorphosis, grouper larval gut develops better immunity fitness with eosinophilic granule cells observed in the intestinal epithelia of day 33 larvae. Future studies on grouper larval nutrition may consider the appropriate dietary phospholipid levels and larval competence to biosynthesize highly unsaturated fatty acid from linoleic acid vis-à-vis the use of plant ingredients in artificial diet formulations. In vivo challenge tests may validate appropriate dietary nutrient supplementation and lead to better feed formulation, matching the varying energetic demands and digestive capacities of developing E. coioides larvae.

"An ape's view of the Oldowan" revisited.

In 1989, Wynn and McGrew published an explicit comparison between Oldowan technology and what was then known of chimpanzee technology. They compared the range and variety of tools, adaptive role of tools, carrying distances, spatial cognition, manufacturing procedures, and modes of learning. They concluded that everything archeologists had reconstructed about the behavior of Oldowan hominins could be accommodated within the ape adaptive grade; that is, a paraphyletic group united by overall similarities in anatomy and, in this case, behavior. The only Oldowan activities that were almost unknown for modern apes were the long-distance transport of objects and direct competition with carnivores, which was implied by meat acquisition activities. "In its general features Oldowan culture was ape, not human. Nowhere in this picture need we posit elements such as language, extensive sharing, division of labor, or pair-bonded families, all of which are part of the baggage carried by the term human."

Efecto del entrenamiento al ejercicio en cifoescoliosis / Effect of exercise training in kyphoscoliosis

FUNDAMENTOS: Analizar el efecto de un programa rehabilitación respiratoria sobre el control de los síntomas respiratorios en pacientes con insuficiencia respiratoria hipercápnica (IRH)secundaria a cifoescoliosis. MÉTODOS: Estudiamos a 15 pacientes, 8 hombres y 7 mujeres, diagnosticados de IRH secundaria a cifoescoliosis, en tratamiento con ventilación mecánica domiciliaria (VMD) al menos durante 6 meses y sin control completo de los síntomas. Iniciamos protocolo de entrenamiento al ejercicio, creando aleatoriamente dos grupos: control y entrenamiento. Al inicio y al final del estudio se les realizó una valoración funcional: espirometría forzada, pletismografía, gasometría arterial, PMI y PME, fuerza muscular periférica (test 1RM), test de esfuerzo máximo y submáximo en cicloergómetro, Shuttle Walking Test (SWT) y disnea por escalas de MRC y BDI/TDI. El grupo entrenamiento: realizó tratamiento con VMD y programa de entrenamiento mixto al ejercicio. El grupo control realizó tratamiento con VMD. RESULTADOS: Con VMD mejoraron significativamente los síntomas por hipoventilación, sin mejoría significativa del síntoma disnea. Tras programa de entrenamiento: el grupo control no mostró cambios significativos en los parámetros evaluados; el grupo entrenamiento mostró cambios significativos en síntoma disnea: tanto basal, de Pre-RR=4(0,75) a Post-RR=3,50 (1) según la escala de MRC, y de Pre-RR=2,33(2) a Post-RR=4(2,33) según índice de disnea basal de Mahler, como tras esfuerzo, de Pre-RR=9(1,75) a Post- RR=7(5) según la escala de Borg tras el test de endurance. Se observó además una mejora en la capacidad de esfuerzo de aquellos pacientes que realizaron el programa de entrenamiento al ejercicio. CONCLUSIONES: La rehabilitación respiratoria (RR) asociada a VMD, consigue mejorar la disnea, capacidad de esfuerzo y por tanto, la calidad de vida en pacientes con cifoescoliosis severa en situación de IRH (AU)

OBJECTIVES: To analyse the effect of a respiratory rehabilitation programme on the control of the respiratory symptoms in patients with hypercapnic respiratory insufficiency (HRF) secondaryto kyphoscoliosis. METHODS: We studied 15 patients, 8 men and 7 women, diagnosed with HRF secondary to kyphoscoliosis, under treatment with home mechanical ventilation (HMV) for at least 6 months and without complete control of the symptoms. We initiated an exercise training protocol, randomly creating two groups: control and training. The patients underwent a functional evaluation at the beginning and at the end of the study consisting of: forced spirometry, plethysmography, arterial gasometry, MIP and MEP, one repetition maximum strength test (1-RM test), maximum and sub-maximum effort tests on a cycloergometer, Shuttle Walking Test (SWT)and dyspnoea by MRC and BDI/TDI scales. The training group: were treated with HMV and a mixed exercise training programme. The control group received treatment with HMV. RESULTS: With HMV the hypoventilation symptoms improved significantly, without significant improvement of the dyspnea symptom. After the training programme: the control group did not show significant changes in the measured parameters; the training group showed significant changes in the dyspnoea symptom: both basal (from Pre-RR = 4[0.75] to Post-RR = 3.50[1] according to the MRC scale, and Pre-RR = 2.33[2] to Post-RR = 4[2.33] according to the basal dyspnoea index of Mahler) and after effort (from Pre-RR = 9[1.75] to Post- RR = 7[5] according to the Borg scale after the endurance test). In addition, an improvement was observed in the effort capacity of those patients who underwent the exercise training programme. CONCLUSIONS: The respiratory rehabilitation (RR) associated to HMV, is able to improve the dyspnoea, effort capacity and therefore, the quality of life in patients with severe kyphoscoliosis in the HRF situation (AU)

Efectos de diferentes estrategias de entrenamiento al ejercicio sobre parámetros antropométricos según el fenotipo del paciente con EPOC / Effects of different exercise training strategies on anthropometric parameters according to the prenotype of the patient with EPOC

OBJETIVO: Analizar el efecto sobre dos parámetros antropométricos de la aplicación de distintas modalidades de entrenamiento al ejercicio en un grupo de pacientes con enfermedad pulmonar obstructiva crónica (EPOC), categorizados según su fenotipo (con o sin predominio de enfisema). METODOLOGIA: 64 pacientes con EPOC estable (edad media de 64,1 ± 6,8 años) que presentan obstrucción moderada severa al flujo aéreo, realizaron un programa de entrenamiento al ejercicio, aleatoriamente distribuidos en tres grupos: resistencia (n=21; entrenamiento aeróbico en bicicleta al 70% de su VO2 máximo inicial), fuerza (n=22; cinco ejercicios de levantamiento de pesas al 70-85% del test 1 RM inicial, incluyendo grupos musculares de MMSS y MMII) y mixto (n=21; combinación de los anteriores).Se subdividieron en pacientes EPOC con predominio de enfisema(n=32) o sin enfisema (n=32) según criterios clínicos, funcionales y radiológicos. Inicialmente y tras 12 semanas de entrenamiento se midieron los cambios en el peso y en el índice de masa corporal (IMC) como parámetros antropométricos. RESULTADOS: Los pacientes EPOC sin enfisema cuyo entrenamiento incluía ejercicios de tipo aeróbico (grupos resistencia y mixto) experimentaron una disminución del IMC (-0,43 ± 1,45 y -0,82 ± 1,04; p<0,05) y del peso (-0,96 ± 4,15 y -2,44 ± 2,96 kg). Los EPOC tipo enfisema cuyo entrenamiento incluía ejercicios de fuerza (fuerza y mixto) presentaron un aumento del IMC (0,42 ± 0,50 y 0,35± 1,04; p<0,05) y del peso (0,91 ± 1,08 y 1,25 ± 2,83 kg; p<0,05). CONCLUSIONES: Distintas estrategias de entrenamiento alejercicio producen efectos diferentes sobre índices antropométricos en pacientes con EPOC, dependiendo del fenotipo que presenten (AU)

OBJECTIVE: To analyse the effect of the application of different modes of exercise training on two anthropometric parameters in a group of patients with chronic obstructive pulmonary disease (COPD), categorised according to their phenotype (with or without predominance of emphysema). METHODOLOGY: Sixty-four patients with stable COPD (average age of 64.1 ± 6.8 years) that presented moderate-severe air flow obstruction, undertook an exercise training programme, randomly distributed in three groups: resistance (n=21; aerobicbicycle training to 70% of their initial maximum VO2), strength(n=22; five weight raising exercises to 70-85% of the initial 1-RMtest, including arm and leg muscle groups) and mixed (n=21; combination of the previous). They were subdivided into COPD patients with predominance of emphysema (n=32) or without emphysema (n=32) according to clinical, functional and radiological criteria. The changes in weight and body mass index (BMI) were measured as anthropometric parameters initially, and after12 weeks of training. RESULTS: COPD patients without emphysema whose training included aerobic type exercises (resistance and mixed groups) experienced a reduction of BMI (-0.43 ± 1.45 and -0.82 ± 1.04;p<0.05) and weight (-0.96 ± 4.15 and – 2.44 ± 2.96 kg). The COPD patients with emphysema whose training included strength exercises (strength and mixed) displayed an increase in BMI (0.42 ± 0.50and 0.35 ± 1.04; p<0.05) and weight (0.91 ± 1.08 and 1.25 ± 2.83 kg; p<0.05). CONCLUSIONS: Different exercise training strategies produce different effects on anthropometric indices in patients with COPD, depending on the phenotype they present (AU)

Euresis infantile: la importancia de una correcta intervención / Childhood enuresis: the importance of a correct intervention

Introducción: la enuresis nocturna monosintomática (ENM) es una enfermedad muy frecuente en la infancia que favorece la aparición de problemas psicológicos y de autoestima; sin embargo, sigue siendo una entidad infravalorada. Objetivos: 1. Conocer las características epidemiológicas y clínicas de una serie de niños enuréticos. 2. Seguir la evolución de estos pacientes desde que acudieron a nuestra consulta hasta el alta. Material y métodos: Estudio descriptivo retrospectivo incluyendo 67 niños derivados a una consulta hospitalaria durante los años 1997-2005 por presentar enuresis. Se recogieron los datos epidemiológicos, clínicos y terapéuticos antes y después de la visita a una consulta especializada. Resultados: Se revisaron 67 pacientes. 76,1% correspondieron a ENM y 23,9% a síndrome enurético. Presentamos 51 casos de ENM (66,7% niños y 33,3% niñas). Existían antecedentes familiares en el 80,4%. Solo el 47,1% había recibido tratamiento previo. La valoración psicosocial resultó normal en el 94,1% y la exploración física en el 92,2%. En el 78,4% se solicitaron pruebas complementarias. Los tratamientos más empleados fueron: pauta básica, desmopresina (45,1%) y desmopresina más anticolinérgicos (33,35%). Aparecieron efectos secundarios relacionados con la desmopresina en el 11,8%. Se curó el 74,5%. Conclusiones: Es necesario concienciar al paciente a sus familiares de este problema y fomentar el tratamiento precoz de la ENM. En la ENM la valoración básica psicosocial y la exploración física son casi siempre normales. Los exámenes complementarios pueden reducirse a un examen de orina. Recordar que el tratamiento requiere tiempo y detectar precozmente sus efectos secundarios es fundamental para evitar el abandono del mismo (AU)

Background. Nocturnal Enuresis is a common illness in childhood that involves psychological and self-esteem problems. However, enuresis is often misunderstood. Objective: 1. Review the main epidemiologic and clinical characteristics of a group of enuretic children. 2. Follow up of these patients from admission until discharge from hospital. Material and methods: Descriptive, retrospective study including 67 children sent to the out patient department during 199-2005 for enuresis. Epidemiological, clinical and treatment data were recorded before and after visiting the specialist. Results: 67 patients were reviewed: 76,1% were found to have Monosyptomatic Nocturnal Enuresis (MNE) and 23,9% were found to have enuretic syndrome. In this study we present 51 cases of MNE (66,7% male and 33,3% female under the age of fourteen years). There was a family history of nocturnal enuresis in 80,4%. In our experience we founded that only 47,1% had received treatment before they arrived at hospital. Psychosocial evaluation was normal in 94,1% and physical examination in 92,2%. In 78,4% of the patients routine exams were carried out. The most frequent treatments were: behavioral intervention, desmopressin 845,1%) and desmopressin + cholinergic antagonists (33,35%). Secondary effects related to desmopressin were observed in 11,8%. 74,5% of the subjects mad a good recovery from enuresis. Conclusions: it is important to make patient and family aware of this problem and to promote the early treatment of MNE. Basic psychosocial examination and physical examination are usually normal in MNE. Routine exams can be reduced to an urine exam. The treatment can be over long duration and the early detection of secondary effects is basic to avoid treatment abandonment (AU)

Effect of Plantago major on cell proliferation in vitro.

Plantago major (Plantaginaceae) is popularly used to treat tumors, infections and as a blood purifier. Aqueous, methanol, chloroform and hexane extracts of the aerial parts (leaves and seeds) were added to CD(1) mice bone marrow and spleen cultures incubated at 37 degrees C for 72h, and also added to Escherichia coli, Bacillus subtilis and Candida albicans cultures, while methanol extract dilutions were added to HTC-15, OVCAR, UISO and KB cell line cultures. Doses of 0.4 and 0.2 mg/mL of aqueous and methanol extracts increased the bone marrow cell concentration by 2.70- and 3.15-fold, respectively, and increased the spleen cell concentration by 3.38- and 6.39-fold, respectively (p < 0.001). Aqueous extract inhibited Bacillus subtilis growth from 78 to 21%; hexane extract inhibited the growth of Escherichia coli, and methanol and chloroform extracts weakly inhibited the growth of Bacillus subtilis and Escherichia coli, respectively. Methanol extract (1 microg/mL) decreased the UISO and OVCAR cell concentrations to 59 and 82%, respectively. Data demonstrate for the first time that Plantago major has hematopoietic activity in vitro.

Effect of Bauhinia forficata extract in diabetic pregnant rats: maternal repercussions.

Bauhinia forficata, commonly known as "paw-of-cow", is widely used in Brazil folk medicine for the treatment of Diabetes mellitus. The purposes of present study were to determine the repercussions of diabetes on the defense system against oxidative stress in pregnant female rats and to characterize the influence of the treatment with Bauhinia forficata extract on the antioxidant system, glycemic control, hepatic glycogen, cholesterol, triglycerides, total proteins and lipids. Virgin female Wistar rats were injected with 40 mg/kg streptozotocin (STZ) before mating. Oral administration of an aqueous extract of Bauhinia forficata leaves was given to non-diabetic and diabetic pregnant rats in 3 doses: 500 mg/kg from 0 to 4th day of pregnancy, 600 mg/kg from 5th to 14th day and 1000 mg/kg from 15th to 20th day. All the females were killed on the day 21 of pregnancy. A maternal blood sample was collected by venous puncture and the maternal liver was removed for biochemical measurement. The diabetic pregnant rats presented hyperglycemia, hyperlipemia, hypertriglyceridemia, hypercholesterolemia, hyperuricemia, decreased determinations of reduced glutathione (GSH) and superoxide dismutase (SOD). Treatment with B. forficata extract did not interfere in the albumin, total protein and lipid, triglyceride, cholesterol and SOD determinations. Increased hepatic glycogen, decreased uric acid concentration and increased GSH activity was observed. This last fact suggests that the plant may have some action on antioxidant defense system. However, the demonstration of the active component present in B. forficata responsible for its antioxidant effect and the increase in hepatic glycogen deserve further investigation.

Differential effects of cohort removal stress on the acoustic startle response of the Roman/Verh rat strains.

Male and female rats of the inbred Roman/Verh strains, which have been psychogenetically selected and bred for good (RHA-I/Verh) and extremely poor (RLA-I/Verh) two-way avoidance acquisition, were evaluated in an acoustic startle response test. One half of the rats of each strain and sex were previously subjected to 30 min of isolation by removal of their cage partners ("cohort removal"). During the testing session each animal received 40 acoustic stimuli at interstimulus intervals of 30 seconds. The hyperemotional RLA-I/Verh rats (especially the males) showed stronger acoustic startle responses than did their RHA-I/Verh counterparts. Startle amplitudes of the RLA-I/Verh males were further enhanced by the stress of 30 min isolation, whereas cohort removal did not significantly affect startle response amplitudes in RHA-I/Verh rats of either sex or in females of the RLA-I/Verh strain.

Gonadotropin and prolactin secretion in prepubertal female rats treated with 8-hydroxy-2-(di-n-propylamino) tetralin.

The effect of serotoninergic activation on gonadotropin and prolactin release were analysed in 16-day-old intact female rats. In the first experiment, females were decapitated 30 min after i.p. administration of 100 mg/kg of 5-hydroxytryptophan (5-HTP) or vehicle; in the second experiment the rats were decapitated 15 and 30 min after i.p. injection of vehicle or some doses (0.1, 1 and 10 mg/kg) of 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT), a selective agonist of the serotonin (5-HT)1A receptors. We found that: 1) serum follicle-stimulating hormone (FSH), luteinizing-hormone (LH) and prolactin concentrations increased after 5-HTP administration; 2) serum LH and prolactin concentrations and pituitary prolactin content increased after administration of 8-OH-DPAT. Our results indicate that in prepubertal rats, activation of serotoninergic system stimulated gonadotropin and prolactin release, and that 5-HT1A receptors are involved in this effect. In addition, the simultaneous increase in serum and pituitary prolactin content suggests that 8-OH-DPAT enhances prolactin synthesis.

Dietary patterns and nutrient intakes of toddlers from low-income families in Denver, Colorado.

Over a 2-year period, dietary and socioeconomic data were collected from 793 food records of 90 toddlers, aged 1 to 2 years, who were predominantly U.S. Hispanics living in low-income households in Denver, CO. This study was part of a larger investigation designed to assess the efficacy of vitamin and mineral supplements in young children. The toddlers were randomly assigned to one of five treatment groups: multivitamin; multivitamin and iron; multivitamin, iron, and zinc; multivitamin and zinc; or placebo. Three-day food records that were collected from the toddlers at the beginning of the study, at 3 months, and at 6 months were used to assess the dietary and nutrient intakes. Meal patterns were devised on the basis of the frequency of food consumption and common food combinations. Nutrient values were calculated using a diet analyzer program. Nutrient analysis of the toddlers' diets indicated that iron and magnesium were consumed least frequently, whereas more than adequate amounts of protein (193% of the Recommended Dietary Allowance) and sodium (207% of minimum requirements for healthy persons) were consumed. No significant differences in nutrient intakes were observed among the treatment groups, suggesting that the vitamin and mineral supplements had no effect. A difference in energy intake was observed over time with the 6-month and 3-month intakes significantly higher than the initial intakes. There was also a high consumption of carbonated beverages. Despite the low income levels of the families, these toddlers were consuming adequate amounts of food; however, an educational component aimed at reducing the toddlers' high intakes of protein, sodium, and carbonated drinks may help improve the present feeding practices of the mothers.

Effect of locus coeruleus and periventricular gray substance lesions on bright light-induced persistent estrous.

To assess the relation between the suprachiasmatic nucleus and the locus coeruleus, persistent estrous was induced in female rats by exposure to constant bright light followed with electrolytic damage of the locus coeruleus. Locus coeruleus lesions resulted in a transient loss of persistent estrous indicated by sustained diestrous aspect of the vaginal smears. There was a direct correlation between duration of estrous loss and the amount of locus coeruleus damage. Simultaneous damage to the periventricular gray substance adjacent to the locus coeruleus prevented the suppression effects of locus coeruleus damage upon persistent estrous. These results suggest a physiological role of the locus coeruleus and periventricular gray substance in the modulation of the neuroendocrine control of ovarian function due to suprachiasmatic nucleus activity.

[Effect of pargyline on the response to CO2 stress]. / Efecto de la pargilina sobre la respuesta al estrés por CO2.

The effects of pargyline administration during three days on male rats for stress reaction caused by hypercapnia, taking into account the contents of noradrenaline in the left auricle, the right auricle, the ventricle, the spleen and the hypothalamus have been studied. The stress by CO2 only produces a significant depletion of noradrenaline at the hypothalamus level. The administration of pargyline (50 mg/kg/day) induces significant increases in the content of noradrenaline in all the tissues. The increases in noradrenaline content are greater when the pargyline is given before the stress.

Convergence of influences from hypothalamus and locus coeruleus upon the olfactory tubercle.

The interaction of locus coeruleus (LC) and lateral hypothalamus (LH) stimulation upon the evoked potentials and unitary activity in the olfactory tubercle (OT) were studied. The difference in latency of the evoked potentials in the OT by LC or by LH stimulation seems to indicate that thin fibers compose the LC-OT pathway and that thick fibers compose the LH-OT pathway. The most common pattern of OT neuronal discharge was in bursts. The train stimulation of the LC decreased the OT neuronal discharge. The LH stimulation produced an increase of the OT neuronal discharge. These results suggest a convergence of LH fibers and LC fibers upon the OT. The nature of the neurotransmitters involved in both pathways is suggested: norepinephrine for the LC-OT projection and dopamine for the LH-OT projection.

Vagus nerve stimulation modifies the electrical activity of the olfactory bulb.

Evoked potential and unit activity recording techniques were used to study the effects of the vagus nerve stimulation on the olfactory bulb. A biphasic potential was evoked in the olfactory bulb by a single pulse delivered to the vagus nerve. Half of the neurons studied decreased discharge frequency after single pulse or train stimulation. The interval during which neurons ceased activity corresponded to the duration of the negative wave of the evoked potential. Responsive neurons were marked with horseradish peroxidase applied iontophoretically. Responsive neurons were located in the periglomerular layer of the olfactory bulb. These results suggest the existence of a vagus nerve-olfactory bulb pathway. The functional significance of this pathway is discussed.

Afferent connections to the lateral hypothalamus: a horseradish peroxidase study in the rat.

Horseradish peroxidase, 13% Sigma Type VI, was administered iontophoretically to the mid lateral hypothalamus (LH) of male hooded rats. Animals were perfused intracardially on the following day and brains were removed and sliced in the coronal or sagittal planes into 30-50 micrometer sections. Sections were processed with DAB and BDH for the brown and blue reaction products and later examined by bright and dark field microscopy for the presence and location of retrogradely labeled neurons. Results indicate that a significant number of afferent connections to the LH originate in the olfactory and accumbens nuclei, pyriform cortex, olfactory tracts, magnocellular and medial preoptic and anterior hypothalamic regions, stria terminalis, stria hypothalamic tract, diagonal tract of Broca, caudate-putamen and globus pallidus, internal capsule, lateral septal nuclei, lateral preoptic area and anterior medial forebrain bundle, the various amygdaloid nuclei, zona incerta, perifornical region, dorsal and ventral medial hypothalamic areas, supraoptic, paraventricular and periventricular nuclei, posterior hypothalamus and medial forebrain bundle, ventral thalamic nuclei, the fields of Forel, arcuate and mammillary nuclei, adjacent to the fasciculus retroflexus, in the ventral tegmental area of Tsai, interpeduncular nucleus, substantia nigra, mesencephalic reticular formation, periaqueductal gray, locus coeruleus and parabrachial region. Results are discussed in terms of previous anatomical and neurophysiological data, probable pathways, and the function of LH neurons.

Effects of cervical vagus nerve stimulation on hypothalamic neuronal activity.

The effects of cervical vagus nerve stimulation on the activity of 56 neurons recorded in various parts of the rat brain were determined. Recordings were made from neurons in both the ipsilateral and contralateral hemispheres during vagus nerve stimulation. Both frequency, 10 to 100 Hz, and voltage, 1 to 20 V, of 0.5 msec pulses were applied to the nerve in a random manner over a 4 sec period while monitoring ongoing single neuronal activity. Frequency response relationships were established for 64% of the lateral preoptic-lateral hypothalamic-medial forebrain bundle (LPA-LH-MFB) neurons which were tested. Four types of LPA-LH-MFB neuronal responses were observed. Twenty percent of the neurons increased in discharge frequency as stimulation frequency was increased, 9% increased in discharge frequency as stimulation frequency was decreased, 23% decreased in discharge frequency as stimulation frequency was increased, and 14% decreased in discharge frequency as stimulation frequency was decreased. Increasing the stimulation voltage always enhanced the magnitude of the effects observed due to changing the stimulation frequency. Neurons observed in some other parts of the brain were not affected by the same stimulation. In addition, cells tested in the LPA-LH-MFB area which were previously tested and affected by gastric distension were also affected similarly by vagus nerve stimulation. Results are discussed in terms of peripheral afferent control over LPA-LH-MFB neuronal activity related to ingestive behavior.