ABSTRACT
Intraspecific flower colour variation has been generally proposed to evolve as a result of selection driven by biotic or abiotic agents. In a polymorphic population of Silene littorea with pink- and white-flowered plants, we studied pollinators, analysed flower colour perception and tested for differences in pollinator visitation. We also experimentally analysed pollinator limitation in fruit and seed set, and the degree of autonomous selfing. The incidence of florivory and leaf herbivory was compared over 3-4 years. Silene littorea is mainly pollinated by bees and butterflies. Pollinators preferred pink flowers, which did not show pollinator limitation. On the contrary, white flowers showed pollinator limitation in fruit set. White-flowered plants had less floral display and higher levels of florivory than pink plants. Flower colour morphs of S. littorea can reproduce in the absence of pollinators by autonomous selfing, setting 20% and 12% of fruit and seeds in the pink morph and 27% and 20% in the white morph, respectively. Fruit set of white flowers produced by autonomous selfing did not differ from open-pollinated flowers. In conclusion, S. littorea is pollinated by insects of different orders that more frequently visit pink flowers, which is reflected in pollinator limitation of fruit set in white flowers. Moreover, this species has a mixed mating system in which both colour morphs can reproduce in the absence of pollinators by autonomous selfing, although white flowers mainly produce fruits by autogamy. We suggest that reproductive assurance by autonomous selfing helps to maintain flower colour polymorphism in this population.
Subject(s)
Flowers , Herbivory , Pigmentation , Pollination , Silene , Animals , Bees/physiology , Butterflies/physiology , Flowers/anatomy & histology , Flowers/chemistry , Flowers/metabolism , Pigmentation/physiology , Pigments, Biological/metabolism , Reproduction/physiology , Silene/chemistry , Silene/parasitology , Silene/physiologyABSTRACT
The phenology of anthocyanin accumulation in leaves has been widely studied in perennial plants; several hypotheses have been proposed to explain their adaptive significance. Here, we explored the photoprotection hypothesis in Silene germana, a Mediterranean annual plant with late-spring/summer flowering. We analysed the temporal patterns of anthocyanin accumulation in photosynthetic calyces, leaves and stems and throughout the reproductive season, and their relationship with flower abortion, florivory and plant mortality due to drought. In addition, the flavonoid production and the photoinhibitory response were measured in a shading experiment. The whole plant becomes red at the end of the flowering and remains red until fruiting and senescence. Calyces were redder on the side with more sun exposition. Aborted flowers showed redder calyces than those of fruiting flowers. No effect of plant redness on florivory or plant mortality was found. The shading experiment showed a positive relationship between anthocyanin accumulation and intensity of solar radiation, but plants growing in absence of UV showed similar redness than full sunlight plants. Plants growing in natural shade lack anthocyanins but produced the same amount of non-anthocyanin flavonoids. Anthocyanic and non-anthocyanic plants showed similar photochemical efficiency (Fv /Fm ) after sun exposition, but in early morning, the former showed lower Fv /Fm values. Plants growing in full sunlight produced more fruits than those of natural shade plants. Whole-plant reddening during fruiting and senescence appears to be a property of S. germana. Our results suggest that anthocyanin accumulation depends on sunlight intensity, but non-anthocyanin flavonoids are produced constitutively.
Subject(s)
Anthocyanins/metabolism , Silene/radiation effects , Chlorophyll/metabolism , Color , Flavonoids/metabolism , Flowers/metabolism , Flowers/radiation effects , Light , Plant Leaves/metabolism , Plant Leaves/radiation effects , Plant Stems/metabolism , Plant Stems/radiation effects , Silene/metabolism , SpectrophotometryABSTRACT
Strikingly, in spite of its physiological importance, information about occurrence, biochemical characteristics and mechanisms of regulation of aminopeptidase-N (APN) in the hepatopancreas of intertidal euryhaline crabs is still lacking. In this work, we determined the occurrence, biochemical characteristics, response to environmental salinity and dopamine of APN in the hepatopancreas of the euryhaline crab Neohelice granulata (Dana 1851) from the open mudflat of Mar Chiquita coastal lagoon (Buenos Aires province, Argentina). APN activity was maximal at pH and temperature range of 7.6-9.0 and 37-45 °C, respectively. APN activity exhibited Michaelis-Menten kinetics (apparent Km = 0.19 ± 0.10 mM) (pH 7.6, 37 °C) and appeared to be sensitive to bestatin (I 50 = 15 mM) and EDTA (I 50 = 9 mM). In crabs acclimated to 10 psu (hyper-regulation conditions) and 37 psu (hypo-regulation conditions), APN activity was about 45 and 160% higher, respectively, than in 35 psu (osmoconformation). APN activity in the hepatopancreas was stimulated in vitro (about 137%) by 10(-4) M dopamine. Higher dopamine concentrations produced a similar extent of increase. The responses of APN activity to salinity and dopamine in vitro suggest the role of APN in digestive adjustments upon hyper and hypo-regulatory conditions and its modulation via direct mechanisms on hepatopancreas by dopamine.
Subject(s)
Acclimatization/physiology , Brachyura/enzymology , CD13 Antigens/metabolism , Hepatopancreas/enzymology , Wetlands , Analysis of Variance , Animals , Argentina , Digestion/drug effects , Digestion/physiology , Dopamine/pharmacology , Edetic Acid , Hydrogen-Ion Concentration , Kinetics , Leucine/analogs & derivatives , Salinity , TemperatureABSTRACT
The empirical solvent scales for polarizability (SP), dipolarity (SdP), acidity (SA), and basicity (SB) have been successfully used to interpret the solvatochromism of compounds dissolved in organic solvents and their solvent mixtures. Providing that the published solvatochromic parameters for the ionic liquids 1-(1-butyl)-3-methylimidazolium tetrafluoroborate, [BMIM][BF4] and 1-(1-butyl)-3-methylimidazolium hexafluorophosphate, [BMIM][PF6], are excessively widespread, their SP, SdP, SA, and SB values are measured herein at temperatures from 293 to 353 K. Four key points are emphasized herein: (i) the origin of the solvatochromic solvent scales--the gas phase, that is the absence of any medium perturbation--; (ii) the separation of the polarizability and dipolarity effects; (iii) the simplification of the probing process in order to obtain the solvatochromic parameters; and (iv) the SP, SdP, SA, and SB solvent scales can probe the polarizability, dipolarity, acidity, and basicity of ionic liquids as well as of organic solvents and water-organic solvent mixtures. From the multiparameter approach using the four pure solvent scales one can draw the conclusion that (a) the solvent influence of [BMIM][BF4] parallels that of formamide at 293 K, both of them miscible with water; (b) [BMIM][PF6] shows a set of solvatochromic parameters similar to that of chloroacetonitrile, both of them water insoluble; and (c) that the corresponding solvent acidity and basicity of the ionic liquids can be explained to a great extent from the cation species by comparing the empirical parameters of [BMIM](+) with those of the solvent 1-methylimidazole. The insolubility of [BMIM][PF6] in water as compared to [BMIM][BF4] is tentatively connected to some extent to the larger molar volume of the anion [PF6](-), and to the difference in basicity of [PF6](-) and [BF4](-).
ABSTRACT
A theoretical analysis of the double proton transfer (PT) in a hydrogen-bonded N-heterocyclic base pair is presented. The calculated (time-dependent density functional theory) double PT barrier calculated for the concerted process of the 7-azaindole C(2h) dimer in the first excited singlet electronic state S(1) conforms well to the kinetic data and the photophysical evidence reported in this article. The calculated PT energy barrier of 4.8 kcal/mol height, and the corresponding zero point energy value, yield for the S(1) state an activation energy barrier of 0.3 kcal/mol. This finding implies that the double PT concerted process is almost barrierless, confirming previous experiments. Upon N-H deuteration of the 7-azaindole dimer, the theoretical excited-state activation energy for the double deuterium transfer is determined to be 1.4 kcal/mol, in agreement with experiment, which in low-temperature spectroscopy is shown to negate excited-state double-deuteron transfer.
ABSTRACT
El proceso de acreditación hospitalaria de Cataluña, además de la obtención de un certificado de calidad, tiene como objetivo fundamental que el conjunto de hospitales catalanes alcancen unos estándares de cal ¡dad homogénea, que repercuta favorablemente sobre el conjunto de prestaciones ofrecidas a los usuarios. En el programa de acreditación vigente en Cataluña desde el 10 de julio de 1991, el órgano acreditador es la propia Administración Sanitaria (Dirección General de Recursos Sanitarios). El manual de acreditación consta de un cuestionario general sanitario compuesto por 27 unidades y un cuestionario específico que abarca aspectos de seguridad contraincendios y seguridad y mantenimiento de las instalaciones. El número total de criterios evaluados es de 745. El proceso de acreditación hospitalaria de Cataluña consta de las siguientes fases: 1) Solicitud de acreditación, 2) autoevaluación, 3) auditorías técnicas, 4) trámite de audiencia al centro, 5) comité de acreditación, 6) certificado de acreditación y 7) seguimiento de las mejoras realizadas (AU)
No disponible
Subject(s)
Humans , Accreditation/trends , Hospitals/standards , 51706 , Technology Assessment, Biomedical , Safety Management/methods , Self-Evaluation Programs/methods , Management Audit/methods , Process Optimization , Hospital Restructuring/standardsABSTRACT
Ethanol (1-20% vol/vol) caused a dose-dependent reduction in the basal rate of acid formation in isolated rabbit gastric glands with a calculated EC(50) value of 4.5 +/- 0.2%. Ethanol also reduced ATP levels in isolated gastric glands and in cultured parietal cells (EC(50): 8.8 +/- 0.4% and 8.5 +/- 0.2%, respectively) and decreased both basal and forskolin-stimulated cAMP levels. In studies carried out in gastric gland microsomes, ethanol inhibited the hydrolytic activity of H+-K+-ATPase(EC(50): 8.5 +/- 0.6%), increased passive proton permeability (EC(50): 7.9%), and reduced H+-K+-ATPase-dependent proton transport (EC(50): 3%). Our results show that the inhibition of gastric acid secretion observed at low concentrations of ethanol (< or =5%) is mainly caused by the specific impairment of H+-K+-ATPase-dependent proton transport across cell membranes rather than inhibition of the hydrolytic activity of H+-K+-ATPase, reduction in the cellular content of ATP, or increase in the passive permeability of membranes to protons, although these changes, in combination, must be relevant at concentrations of ethanol > or =7%.
Subject(s)
Ethanol/pharmacology , Gastric Acid/metabolism , H(+)-K(+)-Exchanging ATPase/physiology , Protons , Adenosine Triphosphate/metabolism , Animals , Biological Transport/drug effects , Biological Transport/physiology , Cells, Cultured , Coloring Agents/pharmacokinetics , Cyclic AMP/metabolism , Gastric Mucosa/drug effects , Gastric Mucosa/metabolism , Gastric Mucosa/pathology , Intracellular Membranes/metabolism , Male , Microsomes, Liver/metabolism , Parietal Cells, Gastric/drug effects , Parietal Cells, Gastric/metabolism , Permeability , Rabbits , Trypan Blue/pharmacokineticsABSTRACT
Propósito: Es importante comunicar los casos de tumores no seminomatosos mediastínicos en la infancia para protocolizar el tratamiento de las metástasis cerebrales. Material y métodos: varón de 13 años con coriocarcinoma en mediastino anterior, múltiples nódulos pulmonares y tac de cráneo normal. Inició tratamiento quimioterápico con excelente respuesta clínica y radiológica. Previo al segundo ciclo de quimioterapia presentó rápida instauración de coma neurológico, muerte por metástasis y hemorragia masiva. Conclusiones: El desarrollo de metástasis cerebrales no detectables al diagnóstico, obligan a discutir la idoneidad de un estudio de extensión intracraneal más exhaustivo, y la conveniencia profiláctica o terapéutica diferente para la diseminación cerebral del coriocarcinoma (AU)
Subject(s)
Adolescent , Male , Humans , Klinefelter Syndrome/complications , Mediastinal Neoplasms/pathology , Carcinoma , Brain Neoplasms , Lung NeoplasmsABSTRACT
The influence of different sulfonylureas on the rate of acid and pepsinogen secretion was studied in isolated rabbit gastric glands. Neither tolbutamide (10-500 microM), chlorpropamide (10-500 microM), glibenclamide (1-50 microM) nor glipizide (1-50 microM) exerted a secretory effect. In contrast, gliquidone caused a marked and dose-dependent stimulation of acid production in gastric glands incubated under basal conditions and potentiated the stimulatory effect of both histamine and carbachol. Gliquidone also increased the rate of pepsinogen release in gastric glands incubated either under basal conditions or in the presence of cholecystokinin-octapeptide or isoproterenol. The secretory effects of gliquidone were associated with a significant increase in the glandular content of cyclic AMP, caused by a competitive inhibition of low-Km cyclic AMP phosphodiesterase. Our results indicate that, among the assayed sulfonylureas, only gliquidone, in the micromolar range, stimulates acid and pepsinogen secretion through a cyclic AMP-dependent mechanism.
Subject(s)
Gastric Acid/metabolism , Gastric Mucosa/drug effects , Hypoglycemic Agents/pharmacology , Pepsinogens/metabolism , Sulfonylurea Compounds/pharmacology , 3',5'-Cyclic-AMP Phosphodiesterases/antagonists & inhibitors , Animals , Calcium/metabolism , Colforsin/pharmacology , Cyclic AMP/metabolism , Dose-Response Relationship, Drug , Gastric Mucosa/metabolism , In Vitro Techniques , Kinetics , Male , RabbitsABSTRACT
OBJECTIVE: Our objective was to carry out a prospective multicenter study of neuroblastoma patients diagnosed between 0 and 12 months of age. PATIENTS AND METHODS: Diagnostic procedures included histology, catecholamine excretion, bone marrow cytology and MIBG-scan. Staging was evaluated according to the INSS classification. After 1992, Simada criteria were used and also N-myc amplification, DNA index and P-glycoprotein determinations in tumoral tissue. The surgical technique employed and complications derived from it were also evaluated. The patients were treated according to stage with multicenter Spanish protocols N-I-87 and N-II-92. Overall survival and event free survival were calculated by actuarial methods. RESULTS: Between October 1987 and June 1992, a total of 140 infants less than one year of age were registered and diagnosed of neuroblastoma, representing 40% of all neuroblastoma cases. Median age was 0.3 years and 73% were less than 6 months of age at diagnosis. The most frequent stage was 1 (35%) followed by 4-S (20%). The frequency of unfavorable prognostic factors was the following: LDH (21%), NSE (14%), ferritin (18%), Shimada (7%), DNA (35%), NMA (3%), TrakA (23%), P-glycoprotein (19%). Surgery was performed in 133 children: total resection was reported in 94 and > 90% in another 22 cases. Complications attributed to surgery occurred in 12% of the cases. Chemotherapy was given in 73 cases and radiotherapy in 7. The five year total survival is 91% and the event free survival 88%. Survival by stages: Stage 1 = 91%, stage 2A = 88%, stage 2B = 100%, stage 3 = 84%, stage 4 = 56% and stage 4-S = 100%. CONCLUSIONS: 1) The majority of neuroblastoma cases in infants less than one year old are diagnosed before six months of age. 2) For this age group stages 1 and 4-S are the most frequently observed. 3) Unfavorable biological factors are less frequent than for children over one year of age and are associated with disseminated disease (advanced stage). 4) The outcome is excellent, except for stage 4 patients. The cases in stage 1 and 2 may be treated by surgery alone. Chemotherapy may be of benefit for stage 3 patients.
Subject(s)
Brain Neoplasms/diagnosis , Neuroblastoma/diagnosis , Age Distribution , Bone Neoplasms/secondary , Brain Neoplasms/mortality , Brain Neoplasms/surgery , Female , Humans , Infant , Infant, Newborn , Liver Neoplasms/secondary , Male , Neuroblastoma/mortality , Neuroblastoma/surgery , Prospective Studies , Survival RateSubject(s)
Fibrosarcoma/congenital , Fibrosarcoma/surgery , Soft Tissue Neoplasms/congenital , Soft Tissue Neoplasms/surgery , Chemotherapy, Adjuvant , Female , Fibrosarcoma/diagnosis , Fibrosarcoma/drug therapy , Humans , Infant, Newborn , Soft Tissue Neoplasms/diagnosis , Soft Tissue Neoplasms/drug therapy , ThighABSTRACT
In vivo studies have demonstrated that hepatic glucose production is poorly responsive to insulin in genetically obese Zucker rats. In this work, we have investigated the modulation by insulin of basal gluconeogenesis, fructose 2,6-bisphosphate levels, and pyruvate kinase and 6-phosphofructo 2-kinase activities in hepatocytes isolated from fed obese (fa/fa) or lean (Fa/-) rats. Gluconeogenesis was estimated by the conversion of a mixture of [14C]lactate-pyruvate to [14C]glucose. Basal gluconeogenesis was significantly reduced in hepatocytes isolated from obese rats compared to that measured in hepatocytes from lean animals (0.63 +/- 0.09 vs. 1.47 +/- 0.05 mumol lactate converted to glucose/g cells.20 min; n = 3-4; P < 0.001). In hepatocytes isolated from lean rats, insulin, without affecting the cellular cAMP concentration, caused a dose-dependent inhibition of the rate of gluconeogenesis, which was accompanied by a significant increase in fructose 2,6-bisphosphate levels and activation of both pyruvate kinase and 6-phosphofructo 2-kinase. In contrast, in hepatocytes isolated from obese (fa/fa) rats, neither basal gluconeogenesis nor any of the other metabolic parameters mentioned were significantly modified by insulin, even when assayed at high hormonal concentrations (10 nM). These results demonstrate a lack of responsiveness of hepatic gluconeogenesis to short term insulin action in genetically obese (fa/fa) rats.
Subject(s)
Gluconeogenesis/drug effects , Insulin/pharmacology , Liver/drug effects , Liver/metabolism , Obesity/genetics , Obesity/metabolism , Animals , Cell Separation , Fructosediphosphates/metabolism , Glucose/metabolism , Lactates/metabolism , Lactic Acid , Male , Phosphofructokinase-2 , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Pyruvate Kinase/metabolism , Rats , Rats, Zucker , Reference ValuesABSTRACT
In different types of mammalian cells, insulin has been shown to promote the release of an inositol phosphate glycan (InsP-glycan) through the hydrolysis of a glycosyl-phosphatidylinositol (glycosyl-PtdIns). This InsP-glycan, which has been demonstrated to be taken up by intact cells, may mediate some of the biological effects of insulin. We have investigated how the insulin resistance expressed in genetically obese (fa/fa) rats affects the glycosyl-PtdIns signaling system in isolated hepatocytes compared to what occurs in hepatocytes isolated from lean (Fa/-) rats. The hepatocyte content of glycosyl-PtdIns was reduced by about 30% in obese rats, with respect to that measured in lean rats (2553 +/- 138 vs. 3334 +/- 115 dpm/mg protein; P < 0.01; n = 5). This reduction was accompanied by a marked blockade of the insulin-mediated glycosyl-PtdIns hydrolysis as well as a decrease (approximately 30%) in the rate of InsP-glycan uptake by the isolated liver cells. Obese Zucker rat hepatocytes also showed a significant decrease in the effects of both insulin and InsP-glycan on the stimulation of glycogen synthesis and the activation of glycogen synthase compared to hepatocytes isolated from lean rats. Our results demonstrate that genetic obesity in Zucker (fa/fa) rats is associated with an impairment of the glycosyl-PtdIns-dependent insulin signaling system.
Subject(s)
Glycosylphosphatidylinositols/physiology , Insulin Resistance , Liver/metabolism , Obesity/metabolism , Animals , Glycogen/biosynthesis , Glycogen Synthase/metabolism , Glycosylphosphatidylinositols/analysis , In Vitro Techniques , Male , Obesity/genetics , RatsABSTRACT
OBJECTIVE: Comparative analysis of left atrial and left ventricle Doppler inflow patterns in patients with essential systemic mild to moderate hypertension and normal global left ventricular systolic function. PATIENTS: A group of out patients with the diagnosis of hypertension referred to the Echocardiographic Laboratory of Egas Moniz Hospital in Lisbon. SETTING: Echocardiographic Doppler prospective study. MATERIAL AND METHODS: We studied a group of 50 patients with the diagnosis of mild to moderate arterial hypertension (Group H), which was compared with a population of 50 normal subjects (Group N). In each case we analysed the pulsed Doppler flow of the right upper pulmonary vein and the diastolic inflow of the left ventricular cavity. We calculated the peak velocities and time velocity integrals of the systolic, diastolic and atrial contraction waves of the pulmonary venous flow and also the systo-diastolic velocity and time velocity integral ratios. In the transmitral Doppler flow analysis we evaluated the peak velocities and time velocity integrals of the early (E wave) and late (A wave) waves, and their time velocity and velocity ratio. We assessed also the isovolumic relaxation time and left ventricular mass index. RESULTS: In groups N and H the peak velocity of the pulmonary venous flow systolic wave was 0.53 +/- 0.15 cm/sec and 0.75 +/- 0.10 cm/sec (p = 0.01), diastolic wave was 0.50 +/- 0.10 cm/sec and 0.41 +/- 0.09 cm/sec (p = 0.03) and atrial contraction wave was 0.18 +/- 0.03 cm/sec and 0.35 +/- 0.08 (p = 0.001), with a systo-diastolic ratio of 1.06 +/- 0.10 and 1.83 +/- 0.10 (p < 0.001), respectively. In these two groups the time velocity integral of the pulmonary venous flow systolic wave was 14.4 +/- 2.6 cm and 17.8 +/- 1.8 cm (p = 0.001), the diastolic wave was 12.5 +/- 3.2 cm and 9.3 +/- 1.3 cm (p = 0.05) and the atrial contraction wave was 4.4 +/- 0.07 cm (p = 0.001), with a systo-diastolic ratio of 1.1 +/- 0.16 and 1.9 +/- 0.12 (p < 0.001), respectively. For the group H and considering the three subgroups, hypertensive patients without anatomical or functional alterations, with isolated diastolic dysfunction and with left ventricular hypertrophy associated to diastolic dysfunction, the velocity systo-diastolic ratio was 1.08 +/- 0.12, 1.57 +/- 0.08 (p < 0.01) and 2.4 +/- 0.08 (p < 0.01) and 2.4 +/- 0.08 (p < 0.001), the systo-diastolic time velocity integral ratio was 1.22 +/- 0.17, 1.72 +/- 0.13 (p < 0.01) and 2.4 +/- 0.15 (p < 0.001), the peak velocity of the atrial contraction wave was 0.28 +/- 0.07, 0.3 +/- 0.08 (p < 0.01) and 0.43 +/- 0.07 (p < 0.001) and its time velocity integral was 4.6 +/- 0.06 cm, 5.6 +/- 0.07 cm (p < 0.01) and 7.0 +/- 0.08 cm (p < 0.001). CONCLUSIONS: Pulsed Doppler study of pulmonary venous flow is significantly abnormal in patients with arterial hypertension. This abnormal pulmonary venous flow pattern has a close relationship with structural and functional alterations of the left ventricle. Combined analysis of the pulsed Doppler inflow at these two cardiac anatomical levels is fundamental to understand the pathophysiology of hypertensive heart disease.
Subject(s)
Echocardiography, Doppler , Hypertension/diagnostic imaging , Adult , Aged , Confidence Intervals , Echocardiography, Doppler/statistics & numerical data , Female , Heart Atria/diagnostic imaging , Heart Atria/physiopathology , Heart Ventricles/diagnostic imaging , Heart Ventricles/physiopathology , Hemodynamics , Humans , Hypertension/epidemiology , Hypertension/physiopathology , Hypertrophy, Left Ventricular/diagnostic imaging , Hypertrophy, Left Ventricular/epidemiology , Hypertrophy, Left Ventricular/physiopathology , Least-Squares Analysis , Male , Middle Aged , Portugal/epidemiology , Prospective StudiesSubject(s)
Geriatric Psychiatry , Health Status Indicators , Age Factors , Aged , Drug Prescriptions/statistics & numerical data , Geriatric Psychiatry/statistics & numerical data , Hospitalization/statistics & numerical data , Humans , Schizophrenia/drug therapy , Schizophrenia/epidemiology , Sex Factors , Spain/epidemiologyABSTRACT
Two types of intradural needles, 25 gauge (Qincke bevel) and 24 gauge (Sprotte type bevel) in 535 intradural anaesthesias were compared. Sprotte type needle is a modification of the Withacre needle. Postspinal total headache had an incidence of 8.9%, being significantly less (p less than 0.01) with the Sprotte needles (4.9 versus 11.8%). Spinal headache were significantly more frequent in women and in patients with an age less than 40 years, and there was no significance between the two needles when patients were older than forty. We conclude that Sprotte bevel needle decreases significatively the incidence of post-puncture headache if the patients are younger than forty, but it is an important fact that the different factors involved: age, sex and needle type, might be taken into account when we need conclusions to be drawn.
