Tree root dynamics in montane and sub-alpine mixed forest patches.

Background and Aims: The structure of heterogeneous forests has consequences for their biophysical environment. Variations in the local climate significantly affect tree physiological processes. We hypothesize that forest structure also alters tree root elongation and longevity through temporal and spatial variations in soil temperature and water potential. Methods: We installed rhizotrons in paired vegetation communities of closed forest (tree islands) and open patches (canopy gaps), along a soil temperature gradient (elevations of 1400, 1700 and 2000 m) in a heterogeneous mixed forest. We measured the number of growing tree roots, elongation and mortality every month over 4 years. Key Results: The results showed that the mean daily root elongation rate (RER) was not correlated with soil water potential but was significantly and positively correlated with soil temperature between 0 and 8 °C only. The RER peaked in spring, and a smaller peak was usually observed in the autumn. Root longevity was dependent on altitude and the season in which roots were initiated, and root diameter was a significant factor explaining much of the variability observed. The finest roots usually grew faster and had a higher risk of mortality in gaps than in closed forest. At 2000 m, the finest roots had a higher risk of mortality compared with the lower altitudes. Conclusions: The RER was largely driven by soil temperature and was lower in cold soils. At the treeline, ephemeral fine roots were more numerous, probably in order to compensate for the shorter growing season. Differences in soil climate and root dynamics between gaps and closed forest were marked at 1400 and 1700 m, but not at 2000 m, where canopy cover was more sparse. Therefore, heterogeneous forest structure and situation play a significant role in determining root demography in temperate, montane forests, mostly through impacts on soil temperature.

Differences in globus pallidus neuronal firing rates and patterns relate to different disease biology in children with dystonia.

BACKGROUND: The pathophysiology underlying different types of dystonia is not yet understood. We report microelectrode data from the globus pallidus interna (GPi) and globus pallidus externa (GPe) in children undergoing deep brain stimulation (DBS) for dystonia and investigate whether GPi and GPe firing rates differ between dystonia types. METHODS: Single pass microelectrode data were obtained to guide electrode position in 44 children (3.3-18.1 years, median 10.7) with the following dystonia types: 14 primary, 22 secondary Static and 8 progressive secondary to neuronal brain iron accumulation (NBIA). Preoperative stereotactic MRI determined coordinates for the GPi target. Digitised spike trains were analysed offline, blind to clinical data. Electrode placement was confirmed by a postoperative stereotactic CT scan. FINDINGS: We identified 263 GPi and 87 GPe cells. Both GPi and GPe firing frequencies differed significantly with dystonia aetiology. The median GPi firing frequency was higher in the primary group than in the secondary static group (13.5 Hz vs 9.6 Hz; p=0.002) and higher in the NBIA group than in either the primary (25 Hz vs 13.5 Hz; p=0.006) or the secondary static group (25 Hz vs 9.6 Hz; p=0.00004). The median GPe firing frequency was higher in the NBIA group than in the secondary static group (15.9 Hz vs 7 Hz; p=0.013). The NBIA group also showed a higher proportion of regularly firing GPi cells compared with the other groups (p<0.001). A higher proportion of regular GPi cells was also seen in patients with fixed/tonic dystonia compared with a phasic/dynamic dystonia phenotype (p<0.001). The GPi firing frequency showed a positive correlation with 1-year outcome from DBS measured by improvement in the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS-m) score (p=0.030). This association was stronger for the non-progressive patients (p=0.006). INTERPRETATION: Pallidal firing rates and patterns differ significantly with dystonia aetiology and phenotype. Identification of specific firing patterns may help determine targets and patient-specific protocols for neuromodulation therapy. FUNDING: National Institute of Health Research, Guy's and St. Thomas' Charity, Dystonia Society UK, Action Medical Research, German National Academic Foundation.

Cryopreservation of Arachis pintoi (leguminosae) somatic embryos.

In this study, we successfully cryopreserved cotyledonary somatic embryos of diploid and triploid Arachis pintoi cytotypes using the encapsulation-dehydration technique. The highest survival rates were obtained when somatic embryos were encapsulated in calcium alginate beads and precultured in agitated (80 rpm) liquid establishment medium (EM) with daily increasing sucrose concentration (0.50, 0.75, and 1.0 M). The encapsulated somatic embryos were then dehydrated with silica gel for 5 h to 20% moisture content (fresh weight basis) and cooled either rapidly (direct immersion in liquid nitrogen, LN) or slowly (1 degree C per min from 25 degree C to -30 degree C followed by immersion in LN). Beads were kept in LN for a minimum of 1 h and then were rapidly rewarmed in a 30 degree C water-bath for 2 min. Finally, encapsulated somatic embryos were post-cultured in agitated (80 rpm) liquid EM with daily decreasing sucrose concentration (0.75 and 0.5 M) and transferred to solidified EM. Using this protocol, we obtained 26% and 30% plant regeneration from cryopreserved somatic embryos of diploid and triploid cytotypes. No morphological abnormalities were observed in any of the plants regenerated from cryopreserved embryos and their genetic stability was confirmed with 10 isozyme systems and nine RAPD profiles.

3D printing of biomedically relevant polymer materials and biocompatibility.

ABSTRACT: Research on polymer materials for additive manufacturing technology in biomedical applications is as promising as it is numerous, but biocompatibility of printable materials still remains a big challenge. Changes occurring during the 3D-printing processes itself may have adverse effects on the compatibility of the completed print. This prospective will put emphasis on the different additives and processes that can have a direct impact on biocompatibility during and after 3D printing of polymer materials.

Preliminary survey of 3D image-guided brachytherapy for cervical cancer at representative hospitals in Asian countries.

3D image-guided brachytherapy (3D-IGBT) has become a standard therapy for cervical cancer. However, the use of 3D-IGBT is limited in East and Southeast Asia. This study aimed to clarify the current usage patterns of 3D-IGBT for cervical cancer in East and Southeast Asia. A questionnaire-based survey was performed in 11 countries within the framework of the Forum for Nuclear Cooperation in Asia. The questionnaire collected the treatment information of patients with cervical cancer who underwent 3D-IGBT. The cumulative external beam radiotherapy and 3D-IGBT doses were summarized and normalized to a biological equivalent dose of 2 Gy per fraction (EQD2) using a linear-quadratic model. Of the 11 institutions representing the participating countries, six (55%) responded to the questionnaire. Overall, data of 36 patients were collected from the six institutions. Twenty-one patients underwent whole-pelvic irradiation and 15 underwent whole-pelvic irradiation with central shielding. Patients received a median of four treatment sessions of 3D-IGBT (range, 2-6). All 3D-IGBT sessions were computed tomography (CT)-based and not magnetic resonance image-based. The median doses to the high-risk clinical target volume D90, bladder D2cc, rectum D2cc and sigmoid colon D2cc were 80.9 Gy EQD2 (range, 58.9-105.9), 77.7 Gy EQD2 (range, 56.9-99.1), 68.0 Gy EQD2 (range, 48.6-90.7) and 62.0 Gy EQD2 (range, 39.6-83.7), respectively. This study elucidated the current patterns of 3D-IGBT for the treatment of cervical cancer in East and Southeast Asia. The results indicate the feasibility of observational studies of CT-based 3D-IGBT for cervical cancer in these countries.

Evaluation of platelet activity by multiple electrode impedance aggregometry in acute coronary syndromes: pilot study in a Brazilian tertiary-care public hospital.

There is no definite recommendation for testing platelet aggregation (PA) in acute coronary syndromes (ACS) due to inconclusive evidence on the usefulness of platelet function tests to guide therapy and improve clinical outcomes. The evaluation of PA with multiple electrode impedance platelet aggregometry (MEA) may be useful to manage antiplatelet therapy and possibly influence patient outcome. The primary aim of this study was to measure PA with MEA in Brazilian patients with ACS and evaluate the association between PA and adverse clinical outcomes. Forty-seven consecutive patients admitted with ACS to a Brazilian tertiary-care public hospital were studied and PA was evaluated using MEA. Patients were followed for six months for the occurrence of all-cause death, acute myocardial infarction, or stroke. Suboptimal inhibition of PA was found in 7 patients (14.9%); 5 (10.6%) in response to ASA (acetylsalicylic acid), 2 (5.0%) to clopidogrel, and none to ticagrelor. Inadequate PA inhibition in response to ASA was significantly associated with the composite end point, but there was no significant association for insufficient PA inhibition in response to clopidogrel. This study suggested that the evaluation of PA in ACS using MEA may identify non-responders to ASA. Larger studies are necessary to define, in a public health scenario, the value of MEA in the management of ACS.

Accelerated hyperfractionated radiotherapy for cervical cancer: multi-institutional prospective study of forum for nuclear cooperation in Asia among eight Asian countries.

PURPOSE: To evaluate the toxicity and efficacy of accelerated hyperfractionated radiotherapy (RT) for locally advanced cervical cancer. METHODS AND MATERIALS: A multi-institutional prospective single-arm study was conducted among eight Asian countries. Between 1999 and 2002, 120 patients (64 with Stage IIB and 56 with Stage IIIB) with squamous cell carcinoma of the cervix were treated with accelerated hyperfractionated RT. External beam RT consisted of 30 Gy to the whole pelvis, 1.5 Gy/fraction twice daily, followed by 20 Gy of pelvic RT with central shielding at a dose of 2-Gy fractions daily. A small bowel displacement device was used with the patient in the prone position. In addition to central shielding RT, intracavitary brachytherapy was started. Acute and late morbidities were graded according to the Radiation Therapy Oncology Group and Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. RESULTS: The median overall treatment time was 35 days. The median follow-up time for surviving patients was 4.7 years. The 5-year pelvic control and overall survival rate for all patients was 84% and 70%, respectively. The 5-year pelvic control and overall survival rate was 78% and 69% for tumors > or = 6 cm in diameter, respectively. No treatment-related death occurred. Grade 3-4 late toxicities of the small intestine, large intestine, and bladder were observed in 1, 1, and 2 patients, respectively. The 5-year actuarial rate of Grade 3-4 late toxicity at any site was 5%. CONCLUSION: The results of our study have shown that accelerated hyperfractionated RT achieved sufficient pelvic control and survival without increasing severe toxicity. This treatment could be feasible in those Asian countries where chemoradiotherapy is not available.

CFD simulation of fluid dynamic and biokinetic processes within activated sludge reactors under intermittent aeration regime.

Due to the aeration system, biological reactors are the most energy-consuming facilities of convectional WWTPs. Many biological reactors work under intermittent aeration regime; the optimization of the aeration process (air diffuser layout, air flow rate per diffuser, aeration length …) is necessary to ensure an efficient performance; satisfying the effluent requirements with the minimum energy consumption. This work develops a CFD modelling of an activated sludge reactor (ASR) which works under intermittent aeration regime. The model considers the fluid dynamic and biological processes within the ASR. The biological simulation, which is transient, takes into account the intermittent aeration regime. The CFD modelling is employed for the selection of the aeration system of an ASR. Two different aeration configurations are simulated. The model evaluates the aeration power consumption necessary to satisfy the effluent requirements. An improvement of 2.8% in terms of energy consumption is achieved by modifying the air diffuser layout. An analysis of the influence of the air flow rate per diffuser on the ASR performance is carried out. The results show a reduction of 14.5% in the energy consumption of the aeration system when the air flow rate per diffuser is reduced. The model provides an insight into the aeration inefficiencies produced within ASRs.

A regional cooperative clinical study of radiotherapy for cervical cancer in east and south-east Asian countries.

PURPOSE: Radiotherapy differed widely in east and south-east Asia because of technical, cultural, and socio-economic differences. With the purpose of standardizing radiotherapy for cervical cancer in the region, an international clinical study was conducted. MATERIALS AND METHODS: Eleven institutions in eight Asian countries participated in the study. Between 1996 and 1998, 210 patients with stage IIIB cervical cancer were enrolled. Patients were treated with a combination of external beam radiotherapy (total dose, 50Gy) and either high-dose-rate (HDR) or low-dose-rate (LDR) intracavitary brachytherapy (ICBT) according to the institutional practice. The planned point A dose was 20-28Gy/4 fractions for HDR-ICBT and 30-40Gy/1-2 fractions for LDR-ICBT. RESULTS: Hundred patients were treated with HDR-ICBT and 110 were treated with LDR-ICBT. The ICBT doses actually delivered to point A ranged widely: 12-32Gy in the HDR group and 26-52.7Gy in the LDR group. The 5-year follow-up rate among the countries differed greatly, from 29% to 100%. The 5-year major complication rates were 6% in the HDR group and 10% in the LDR group. The 5-year overall survival rates were 51.1% in the HDR group and 57.5% in the LDR group. CONCLUSIONS: Although there were several problems with treatment compliance and patients' follow-up, the study suggests that the protocols provided favorable outcomes with acceptable rates of late complications in the treatment of advanced cervical cancer in east and south-east Asia.

Cryopreservation of seeds and in vitro-cultured protocorms of Oncidium bifolium sims. (Orchidaceae) by encapsulation-dehydration.

Encapsulation-dehydration was employed for cryopreserving seeds and in vitro-cultured protocorms of Oncidium bifolium. Freshly harvested seeds, 120 days after pollination, were encapsulated in beads containing 1/2 MS medium with 3% sucrose and 3% calcium alginate and subsequently pretreated in agitated (80 rpm) liquid medium supplemented with 0.15 M sucrose (24 h) followed by 0.25 M sucrose (48 h), 0.5 M sucrose (24 h) and 0.75 M sucrose (24 h). The beads with seeds were dehydrated with silica gel for 5 h to 19.2% moisture content and immersed in liquid nitrogen for 1 h, thawed at 30 degrees C for 2 min, post-treated using the same series of liquid media [0.5 M sucrose (24 h), 0.25 M sucrose (48 h), 0.15 M sucrose (24 h)], and recultured on 1/2 MS medium with 0.1M sucrose and 0.7% percent agar. As much as 4.8% of the cryopreserved seeds produced complete plants. In-vitro cultured protocorms were successfully cryopreserved following the same procedure, allowing 11.3% of them to produce plants.

Characterization of (Na+ + K+)-ATPase-liposomes. III. Controlled activation and inhibition of symmetric pumps by timed asymmetric ATP, RbCl, and cardiac glycoside addition.

Inside-out as well as right-side-out oriented (Na+ + K+)-ATPase molecules reconstituted in liposomes are activated successively by timed asymmetric addition of ATP to the internal and external liposome compartment; this presents the first functional confirmation of the symmetric pump-orientation in cholate-dialysed preparations revealed previously by the equal distribution of intramembrane particles on the concave and convex surface of freeze-fractured (Na+ + K+)-ATPase-liposomes. The initial transport rates of the symmetrically oriented pump populations are regulated by varying the bilateral K or Rb ion concentrations; ATP, ouabain, digoxin or vanadate are used to activate or block selectively the right-side-out, inside-out or both (Na+ + K+)-ATPase populations. Finally, these liposomes of the second generation present a new tool to evaluate the membrane-permeability as well as the effects of receptor-ligands or other probes in a single preparation.

Effect of moderate malnutrition on concentrations of immunoglobulins and enzymes in tears and saliva of young Colombian children.

The influence of moderate malnutrition on immunoglobulins and enzymes in the sera and secretions of 71 Colombian children was studied. Concentrations of immunoglobulin A, immunoglobulin G, lysozyme, albumin, and aminopeptidase were measured in the sera, tears, and saliva of 27 normal, 32 grade I, 9 grade II, and 3 grade III malnourished children. The most severely malnourished children, grades II and III, had markedly reduced immunoglobulin A concentrations and elevated immunoglobulin G concentrations in tears. Immunoglobulin A levels in whole saliva were also reduced in these malnourished children. In contrast, the concentration of immunoglobulin A in the sera of these children was significantly elevated. There was no influence of malnutrition on levels of lysozyme, albumin, total protein, and aminopeptidase in tears or saliva. These results indicate that secretory immunity may be impaired in moderately malnourished children due to decreased levels of immunoglobulin A in secretions.

Development of impaired cell-mediated immunity in mild and moderate malnutrition.

The development of moderate malnutrition and cell-mediated immune function was studied in 71 Colombian infants from birth through 2 yr of age. Based upon weight-for-age criteria 31 remained normal, 33 were classified as grade I, and seven were grade II malnourished at the end of their 2nd yr of life. Delayed hypersensitivity reactions to purified protein derivative were significantly reduced in all malnourished children 8 wk after Bacille Calmette-Guerin vaccination at birth, and also at 2 yr in the Grade II group. Nearly half of the latter group could not be sensitized to dinitrochlorobenzene at 2 yr of age. A 50% reduction in the blastogenic response of peripheral blood lymphocytes to phytohemagglutinin in vitro was detected in grade II children. Both mildly and moderately malnourished infants exhibited a significant reduction in tonsil size at 2 yr of age. These results indicate that a majority of newborns in this poor, urban setting will develop measurable malnutrition associated with impaired cell-mediated immune function before their 2nd birthday.

Drop-out reasons and complications in self-injection therapy with a triple vasoactive drug mixture in sexual erectile dysfunction.

The usefulness, complications and reasons for discontinuing the self-injection program with a combination of papaverine, phentolamine and prostaglandin E1 were evaluated in 189 patients (mean age 57.2 y), who were included from April 1993 to September 1995 (mean follow-up 10.25 months). Patients were split into two groups: Active, those who continued with the program (48%); and Inactive, those who discontinued treatment or failed to attend consultation after five months from the last visit (52%). Only 30% of the inactive group reported failure to achieve response with the self-injected doses. Fibrosis in 5.3% and prolonged erection in 3.7% were the most severe complications. Patients lacking organic pathology showed a clear tendency to reduce the drug dose during treatment, recover spontaneous erections and discontinue the program for reasons unrelated to drug efficacy. The triple drug mixture provides an effective alternative in the treatment of impotence, with a low rate of complications.

Response of the premature fetus to stimulation by speech sounds.

The response of the premature fetus to speech stimuli was studied in 41 healthy pregnant patients at 26-34 weeks gestation. Speech stimuli consisted of repeated syllables ('ee' and 'ah') presented externally over the maternal abdomen at either 100, 105, or 110 decibels (dB). Sound stimuli were delivered during periods of both high and low fetal heart rate variability. During periods of low FHR variability, a decrease in fetal heart rate and an increase in the standard deviation of heart rate were found. During periods of high FHR variability, no significant change in either of these measures was observed. This is the first clear demonstration of heart rate responses to speech stimuli in the premature fetus. As is the case in the term fetus, this response is dependent on baseline heart rate variability which is the primary determinant of fetal state. The clinical usefulness of this finding may be limited by the magnitude of the response.

Patterns of development in fetal breathing activity in the latter third of gestation of the baboon.

Patterns of fetal breathing activity were examined in a longitudinal study of the fetal baboon over the latter third of gestation. More than 1400 h of recorded tracheal fluid pressure in 16 or 24 h records from seven fetuses over a range in gestation from 121 to 172 days (term, 175-180 days) were analyzed. In these 81 records, there was a high degree of variability in the percent of time spent breathing by the fetuses (range, 14-83%) with no apparent influence of gestational age (mean +/- S.D., 45.6 +/- 17.6%). Nonetheless, the mean amplitude of fetal breaths increased with gestation from absolute values of about 5-10 mmHg (r = 0.73, P < 0.001) and the mean inspiratory time interval increased from about 0.45-0.55 s (r = 0.40, P < 0.001). During epochs of breathing, the mean rate decreased from about 42-36 breaths per min (r = -0.54, P < 0.001) and the indices of both short term (r = -0.54, P < 0.001) and long term (r = -0.73, P < 0.001) variability in rate decreased. These results demonstrate a clearly defined pattern of development in the breathing activity of the fetal baboon which is comparable to the pattern described for the human fetus in the third trimester of gestation. These similarities suggest that the progressive functional maturation of the mechanisms generating respiratory patterns are comparable among primate species.

Plant regeneration in Arachis pintoi (Leguminosae) through leaf culture.

Plant regeneration in Arachis pintoi was obtained via two developmental pathways: organogenesis and somatic embryogenesis. Organogenic callus cultures were initiated from pieces of leaf on MS medium supplemented with NAA or 2,4-D in combination with BA, KIN or 2iP. The most suitable combination for plant regeneration through organogenesis was an initial medium composed of 10 mg/l NAA+1 mg/l BA followed by transfer of the callus to a shoot induction medium (MS+1 mg/l BA). Rooting of regenerated shoots was readily achieved by culture on MS+0.01 mg/l NAA. Embryogenic callus cultures were initiated from pieces of leaf on MS medium supplemented with PICL in combination with KIN, ZEA, BA or 2iP, and the most suitable combinations were 20 mg/l PICL+1 mg/l BA or 2iP. When pieces of embryogenic callus were subcultured on MS+1 mg/l BA, somatic embryos were differentiated and developed further into well-developed plants in MS+1 g/l AC followed by MS medium devoid of plant growth regulators.

Method for processing of fetal breathing epoch analysis: studies in the primate.

An automated method for detecting fetal breathing and an analytic technique for providing significant data reduction that take the episodic nature of fetal breathing activity into account are described. The aim of the new technique, called epoch analysis, is to derive parameters of breathing and apnea that both summarize the activity and permit examination of its relationship to changes that occur naturally during day and night and with fetal maturation. The discussion covers: the acquisition of data from pregnant baboons; the breath detection process, for which a program was written; the recognition of breathing; computer recognition of artifacts; epoch characterization; validation of the methods of breath detection and epoch characterization; and application of the method. It is found that the technique has a broad capacity for data reduction and provides summaries of the activity that are amenable to analysis with standard statistical techniques.

Typology and correlates of sexual abuse in children and youth: multivariate analyses in a prevalence study in Geneva.

OBJECTIVE: Child sexual abuse (CSA) encompasses a variety of distinct situations, which should be differentiated. There is a need for a working classification, taking into account various parameters. METHODS: The Geneva CSA prevalence study was based on 1116 randomly selected adolescents aged 14 to 16. Secondary analyses of the 252 reported cases of abuse was carried out using a multivariate approach combining multiple correspondence analysis and automatic classification, leading to descriptive analyses and to a new classification of CSA. RESULTS: Global prevalence of CSA, using a broad definition, was 10.9% for boys, and 33.8% for girls. Classification of cases of abuse differentiated 5 classes: (A) exhibitionism or other abuse without contact, by an adult (proportion of cases in boys: 22%; girls: 32%); (B) abuse of an adolescent boy by a peer without contact (62%); (C) abuse of an adolescent girl by a peer with physical contact (38%); (D) abuse inside the family, repeated (boys: 10%, girls: 16%); (E) child abuse with genital penetration, lasting 2 years or more (boys: 7%; girls: 14%). CONCLUSIONS: CSA is a complex and heterogeneous problem. Reported abuse situations can be classified into five classes, with different degrees of severity, causes, and consequences. Classification is essential in clinical research as well as in the design and conception of prevention programs.

Skin-to-skin contact beginning in the delivery room for Colombian mothers and their preterm infants.

To determine if the transition to extrauterine life is facilitated by skin-to-skin contact, six relatively low risk preterm infants experienced six continuous hours of skin-to-skin contact on their mothers' chests beginning within 30 minutes of birth. Heart and respiratory rates and oxygen saturation remained within normal limits and all infant temperatures rose rapidly to thermoneutral range. Two infants developed grunting respirations by the time skin-to-skin contact began, but the grunting disappeared with warm, humidified oxygen and continuous skin-to-skin contact. All infants were fully breastfeeding and ready for discharge by 24-48 hours postbirth. Early skin-to-skin contact was safe and seemed beneficial for these relatively low risk preterm infants.