Identification of soluble type of membrane-type matrix metalloproteinase-3 formed by alternatively spliced mRNA

Homology screening for human membrane-type MMP (MT–MMP) was carried out, and cDNA encoding a soluble type of MT3–MMP (SM3), which is considered to be an alternatively spliced variant of MT3–MMP, was obtained. SM3 had a novel sequence consisting of 50 amino acids after Lys407 instead of amino acids containing the transmembrane domain of MT3–MMP. When SM3 tagged with a FLAG epitope (SM3–flag) was expressed in COS-7 cells, SM3–flag was present in the conditioned medium in its activated form. The enzymatic activity of SM3 was studied using a recombinant enzyme expressed in E. coli (SM3-e). The fluorogenic peptide substrate hydrolyzing activity of SM3-e was inhibited by EDTA and by the tissue inhibitor of metalloproteinase-2 (TIMP-2), whereas TIMP-1 had only relatively weak inhibitory ability. SM3-e was able to activate proMMP-2, and this activity was also inhibited by TIMP-2 but not by TIMP-1. SM3-e was able to cleave type III collagen, and also digested fibronectin. In view of the homology of the primary structures, MT3–MMP was considered to have the same catalytic activity as SM3. The results of studies of SM3's activity on extracellular matrix (ECM) protein suggests that MT3–MMP plays a role in ECM turnover not only by activating proMMP-2 but also by acting directly on ECM macromolecules.     

Pituitary estrogen receptor α and dopamine subtype 2 receptor gene expression in transgenic mice with overproduction of heterologous growth hormones

 Pituitary somatotrophs are suppressed in mice transgenic for human (h) or bovine (b) growth hormone (GH) genes fused with metallothionein (MT) or phosphoenolpyruvate carboxykinase (PEPCK) promoters. Previous morphologic studies revealed that lactotrophs are inhibited in hGH transgenic lines probably due to prolactin-like effects of hGH whereas in female bGH transgenics, the lactotrophs are stimulated. In the present study, estrogen receptor (ERα) mRNA was studied by autoradiographic in situ hybridization (ISH), ERα protein by immunocytochemistry, and dopamine subtype 2 receptor (D2R) mRNA by ISH. In MT/ and PEPCK/hGH transgenic mice, silver grains signaling ERα mRNA were significantly decreased compared to controls; the reduction was stronger in males (8.6 and 37%) than in females (4.6 and 11%). The decrease in the number of ERα-immunoreactive nuclei followed the same pattern (13.3 and 6% in males vs 3.2 and 5.2% in females). In MT/hGH mice the D2R mRNA signal was significantly increased in males (6 and 15.4%) and females (16%). In MT/bGH transgenics, ERα mRNA and ERα-immunoreactive nuclei were significantly increased (25 and 6%) only in males; D2R mRNA was more decreased in females (23%) than in males (15%). In conclusion, the opposite changes in ERα and D2R gene expressions are correlated with lactotroph inhibition in hGH transgenic mice and their stimulation in bGH transgenic mice. The changes in ERα expression were stronger in males, whereas those of D2R were more pronounced in females. Accepted: 16 November 1998     

Abnormal Behavior of Nuclei and Microtubule (MT) Organizational Changes During Embryo Sac Development in the Poly-Egg Mutant,APⅣ of Rice

APⅣ is a rice mutant that develops poly-egg apparatus in its embryo sac. All the eggs that make up the poly-egg apparatus can be fertilized respectively resulting in the development of polyembryony. The routes taken in the development of polyembryony appear to fall mainly into three variant polygonum pattern types, designated as 5-2-1 , 5-3-0 and 6-2-0 types. Out of the embryo sacs of APⅣ studied about 50% exhibited variant polygonum type with associated abnormal nuclear behavior and microtubule organizational changes. Some of the major abnormal features shown by the three variant polygonum types were described and they included the following: For the 5-2-1 type At the beginning of the four-nucleate embryo sac development, one pair of nuclei became located to the micropylar end and the other pair to the chalazal end. As embryo sac further developed, long connecting microtubule (MT) bundles that existed between the two nuclei in the chalazal end play a role in the movement and positioning of that nucleus. As a result of the activities of these MT, one of the nuclei in the chalazal end moved to the micropylar end resulting in the micropylar end having three nuclei and the chalazal end only one. For the 5-3-0 type In the two-nucleate embryo sac of the 5-3-0 type, one nucleus remained at the micro-pylar end, while the other one became located near the central region. In the four-nucleate embryo sac, the pair of nuclei aligned in parallel to the micropylar-chalazal axis often having one of its nuclei relocated to the micropylar end as a result of associated MT activities. For the 6-2-0 type All the nuclei in the megaspore, two- and four-nucleate embryo sacs became located to the micropylar end. At the early stages of the eight-nucleate embryo sac development, the two nuclei in the central region of the embryo sac (originally at the micropylar end) became polar nuclei. All the other nuclei remained at the micropylar end were surrounded by reticulate MT. The relationship between abnormal behavior of nuclei and MT organi-zation in the development of rice embryo sac was discussed.     

Patients with aortic stenosis referred for TAVI: treatment decision, in-hospital outcome and determinants of survival

Aims

To assess treatment decision and outcome in patients referred for transcatheter aortic valve implantation (TAVI) in addition to predictive factors of mortality after TAVI.

Methods

Three-centre prospective observational study including 358 patients. Endpoints were defined according to the Valve Academic Research Consortium.

Results

Of the 358 patients referred for TAVI, TAVI was performed in 235 patients (65%), surgical aortic valve replacement (AVR) in 24 (7%) and medical therapy (MT) in 99 (28%). Reasons to decline TAVI in favour of AVR/MT were patient preference (29%), peripheral vascular disease (15%) and non-severe aortic stenosis (11%). The logistic EuroSCORE was significantly higher in patients who underwent TAVI and MT in comparison with those undergoing AVR (19 vs. 10%, p = 0.007). At 30 days, all-cause mortality and the combined safety endpoint were 9 and 24% after TAVI and 8 and 25% after AVR, respectively. All-cause mortality was significantly lower in the TAVI group compared with the MT group at 6 months, 1 year and 2 years (12% vs. 22%, 21% vs. 33% and 31% vs. 55%, respectively, p < 0.001). Multivariable analysis revealed that blood transfusion (HR: 1.19; 95% CI: 1.05–1.33), pre-existing renal failure (HR: 1.18; 95% CI: 1.06–1.33) and STS score (HR: 1.06; 95% CI: 1.02–1.10) were independent predictors of mortality at a median of 10 (IQR: 3–23) months after TAVI.

Conclusions

Approximately two-thirds of the patients referred for TAVI receive this treatment with gratifying short- and long-term survival. Another 7% underwent AVR. Prognosis is poor in patients who do not receive valve replacement therapy.     

Ascending projections to the hypothalamus and limbic nuclei from the dorsolateral pontine tegmentum: a biochemical and electron microscopic study.

Axons arising from the dorsolateral pontine tegmentum of the rat were traced in various hypothalamic and limbic nuclei by the electron microscopic degeneration method (0.5-8 day survival times) and by measuring regional norepinephrine (NE) concentrations after 12 days of survival using a radioenzymatic method. Significant reductions (41-85%) in NE contents were observed in the supraoptic, arcuate, basal and lateral amygdaloid nuclei and in the hippocampus 12 days after the bilateral electrolytic lesions of the locus coeruleus. No changes in NE concentrations were observed in the ventromedial, septal, central amygdaloid nuclei, in the median eminence and olfactory tubercle. Parabrachial lesions resulted in a decrease of NE content only in the olfactory tubercle. By means of electron microscopy terminal degeneration was found in the hypothalamic paraventricular, dorsomedial nuclei, in the median eminence, in the bed nucleus of the stria terminalis, in the central, lateral and basal amygdaloid nuclei, in the hippocampus and in the anterior ventral thalamic nucleus.     

Nuclear transfer of synchronized african wild cat somatic cells into enucleated domestic cat oocytes

The African wild cat is one of the smallest wild cats and its future is threatened by hybridization with domestic cats. Nuclear transfer, a valuable tool for retaining genetic variability, offers the possibility of species continuation rather than extinction. The aim of this study was to investigate the ability of somatic cell nuclei of the African wild cat (AWC) to dedifferentiate within domestic cat (DSH) cytoplasts and to support early development after nuclear transplantation. In experiment 1, distributions of AWC and DSH fibroblasts in each cell-cycle phase were assessed by flow cytometry using cells cultured to confluency and disaggregated with pronase, trypsin, or mechanical separation. Trypsin (89.0%) and pronase (93.0%) yielded higher proportions of AWC nuclei in the G0/G1 phase than mechanical separation (82.0%). In contrast, mechanical separation yielded higher percentages of DSH nuclei in the G0/G1 phase (86.6%) than pronase (79.7%) or trypsin (74.2%) treatments. In both species, pronase induced less DNA damage than trypsin. In experiment 2, the effects of serum starvation, culture to confluency, and exposure to roscovitine on the distribution of AWC and DSH fibroblasts in various phases of the cell cycle were determined. Flow cytometry analyses revealed that the dynamics of the cell cycle varied as culture conditions were modified. Specifically, a higher percentage of AWC and DSH nuclei were in the G0/G1 phase after cells were serum starved (83% vs. 96%) than were present in cycling cells (50% vs. 64%), after contact inhibition (61% vs. 88%), or after roscovitine (56% vs. 84%) treatment, respectively. In experiment 3, we evaluated the effects of cell synchronization and oocyte maturation (in vivo vs. in vitro) on the reconstruction and development of AWC-DSH- and DSH-DSH-cloned embryos. The method of cell synchronization did not affect the fusion and cleavage rate because only a slightly higher percentage of fused couplets cleaved when donor nuclei were synchronized by serum starvation (83.0%) than after roscovitine (80.0%) or contact-inhibition (80.0%). The fusion efficiency of in vivo and in vitro matured oocytes used as recipient cytoplasts of AWC donor nuclei (86.6% vs. 85.2%) was similar to the rates obtained with DSH donor nuclei, 83.7% vs. 73.0%, respectively. The only significant effect of source of donor nucleus (AWC vs. DSH) was on the rate of blastocyst formation in vitro. A higher percentage of the embryos derived from AWC nuclei developed to the blastocyst stage than did embryos produced from DSH nuclei, 24.2% vs. 3.3%, respectively (P < 0.05). In experiment 4, the effect of calcium in the fusion medium on induction of oocyte activation and development of AWC-DSH-cloned embryos was determined. The presence of calcium in the fusion medium induced a high incidence of cleavage of DSH oocytes (54.3%), while oocyte cleavage frequency was much lower in the absence of calcium (16.6%). The presence or absence of calcium in the fusion medium did not affect the fusion, cleavage, and blastocyst development of AWC-DSH-cloned embryos. In experiment 5, AWC-DSH-cloned embryos were transferred to the uteri of 11 synchronized domestic cat recipients on Day 6 or 7 after oocyte aspiration. Recipients were assessed by ultrasonography on Day 21 postovulation, but no pregnancies were observed. In the present study, after NT, AWC donor nuclei were able to dedifferentiate in DSH cytoplasts and support high rates of blastocyst development in vitro. Incomplete reprogramming of the differentiated nucleus may be a major constraint to the in vivo developmental potential of the embryos.     

Cytoplasmic trafficking, endosomal escape, and perinuclear accumulation of adeno-associated virus type 2 particles are facilitated by microtubule network

Understanding adeno-associated virus (AAV) trafficking is critical to advance our knowledge of AAV biology and exploit novel aspects of vector development. Similar to the case for most DNA viruses, after receptor binding and entry, AAV traverses the cytoplasm and deposits the viral genome in the cell nucleus. In this study, we examined the role of the microtubule (MT) network in productive AAV infection. Using pharmacological reagents (e.g., nocodazole), live-cell imaging, and flow cytometry analysis, we demonstrated that AAV type 2 (AAV2) transduction was reduced by at least 2-fold in the absence of the MT network. Cell surface attachment and viral internalization were not dependent on an intact MT network. In treated cells at 2 h postinfection, quantitative three-dimensional (3D) microscopy determined a reproducible difference in number of intracellular particles associated with the nuclear membrane or the nucleus compared to that for controls (6 to 7% versus 26 to 30%, respectively). Confocal microscopy analysis demonstrated a direct association of virions with MTs, further supporting a critical role in AAV infection. To investigate the underling mechanisms, we employed single-particle tracking (SPT) to monitor the viral movement in real time. Surprisingly, unlike other DNA viruses (e.g., adenovirus [Ad] and herpes simplex virus [HSV]) that display bidirectional motion on MTs, AAV2 displays only unidirectional movement on MTs toward the nuclei, with peak instantaneous velocities at 1.5 to 3.5 μm/s. This rapid and unidirectional motion on MTs lasts for about 5 to 10 s and results in AAV particles migrating more than 10 μm in the cytoplasm reaching the nucleus very efficiently. Furthermore, electron microscopy analysis determined that, unlike Ad and HSV, AAV2 particles were transported on MTs within membranous compartments, and surprisingly, the acidification of AAV2-containing endosomes was delayed by the disruption of MTs. These findings together suggest an as-yet-undescribed model in which after internalization, AAV2 exploits MTs for rapid cytoplasmic trafficking in endosomal compartments unidirectionally toward the perinuclear region, where most acidification events for viral escape take place.     

Patterns of Brain Activation and Meal Reduction Induced by Abdominal Surgery in Mice and Modulation by Rikkunshito

Abdominal surgery inhibits food intake and induces c-Fos expression in the hypothalamic and medullary nuclei in rats. Rikkunshito (RKT), a Kampo medicine improves anorexia. We assessed the alterations in meal microstructure and c-Fos expression in brain nuclei induced by abdominal surgery and the modulation by RKT in mice. RKT or vehicle was gavaged daily for 1 week. On day 8 mice had no access to food for 6–7 h and were treated twice with RKT or vehicle. Abdominal surgery (laparotomy-cecum palpation) was performed 1–2 h before the dark phase. The food intake and meal structures were monitored using an automated monitoring system for mice. Brain sections were processed for c-Fos immunoreactivity (ir) 2-h after abdominal surgery. Abdominal surgery significantly reduced bouts, meal frequency, size and duration, and time spent on meals, and increased inter-meal interval and satiety ratio resulting in 92–86% suppression of food intake at 2–24 h post-surgery compared with control group (no surgery). RKT significantly increased bouts, meal duration and the cumulative 12-h food intake by 11%. Abdominal surgery increased c-Fos in the prelimbic, cingulate and insular cortexes, and autonomic nuclei, such as the bed nucleus of the stria terminalis, central amygdala, hypothalamic supraoptic (SON), paraventricular and arcuate nuclei, Edinger-Westphal nucleus (E-W), lateral periaqueduct gray (PAG), lateral parabrachial nucleus, locus coeruleus, ventrolateral medulla and nucleus tractus solitarius (NTS). RKT induced a small increase in c-Fos-ir neurons in the SON and E-W of control mice, and in mice with surgery there was an increase in the lateral PAG and a decrease in the NTS. These findings indicate that abdominal surgery inhibits food intake by increasing both satiation (meal duration) and satiety (meal interval) and activates brain circuits involved in pain, feeding behavior and stress that may underlie the alterations of meal pattern and food intake inhibition. RKT improves food consumption post-surgically that may involve modulation of pain pathway.     

Early post-pollination events in hexaploid wheat × maize crosses

Summary Cytological events in the first 12 h after pollination were studied in crosses between the hexaploid wheat genotype Chinese Spring and the maize genotype Seneca 60. A pollen tube was first observed in the embryo sac 4 h after pollination, and maize sperm nuclei were first observed in the embryo sac after 5 h. On 29 occasions two, and on 1 occasion three, pollen tubes penetrated the embryo sac. Four categories of aberration limiting the frequency of fertilization were identified: (1) in 20% of florets no pollen tube reached the embryo sac; (2) in at least 1.9% the pollen tube severely damaged the wheat egg cell and polar nuclei; (3) in 33% the maize sperm nuclei were not released from the pollen tube; and (4) in 16% the sperm nuclei were released into the embryo sac but failed to move to either of the wheat gametes. In the remaining 29% sperm nuclei were more often found in the egg cell than at the polar nuclei. The results suggest that karyogamy occurs with very high efficiency when a sperm nucleus reaches the egg cell, but with only about 50% efficiency when a sperm nucleus reaches the polar nuclei.     

Mitosis and mitotic wave propagation in the coenocytic alga,<Emphasis Type="Italic"> Vaucheria terrestris</Emphasis> sensu Goetz

Mitosis and cytoplasmic microtubule (MT) dynamics were observed for the first time in Vaucheria terrestris sensu Goetz. Mitosis could occasionally be seen in part of the cylindrical coenocytic cell. The frequency of encountering cells with dividing nuclei was highest (ca 12%) 4 h after the onset of light in 12 h light/12 h dark regimes; it decreased thereafter and approached zero during the dark period. From the anterior end of every interphase nucleus a unique, long MT bundle extended. Differential-interference optics reveals that there is a filamentous structure in front of the moving nucleus. In prophase, the interphase bundle disappeared and shorter MT bundles emanated from both ends of the nucleus. In metaphase, the cytoplasmic MTs completely disappeared, probably being recycled to spindles. Continuous MTs elongated in anaphase and developed into an interzonal spindle in telophase; this elongated up to as much as 10 m. The daughter nuclei were pushed away from each other by the interzonal spindle. Mitosis started synchronously in a relatively narrow region, and the mitotic stage propagated as a mitotic wave to adjacent regions, most frequently from tip to base. The role of the mitotic wave in tip growth and morphogenesis of a coenocytic cell is discussed.This paper is dedicated to the memory of Dr. Eiji Kamitsubo who passed away on 25 April 2003.     

Skeletal Characterization of Smurf2-Deficient Mice and In Vitro Analysis of Smurf2-Deficient Chondrocytes

Overexpression of Smad ubiquitin regulatory factor 2 (Smurf2) in chondrocytes was reported to cause spontaneous osteoarthritis (OA) in mice. However, it is unclear whether Smurf2 is involved in bone and cartilage homeostasis and if it is required for OA pathogenesis. Here we characterized age-related changes in the bone and articular cartilage of Smurf2-deficient (MT) mice by microCT and histology, and examined whether reduced Smurf2 expression affected the severity of OA upon surgical destabilization of the medial meniscus (DMM). Using immature articular chondrocytes (iMAC) from MT and wild-type (WT) mice, we also examined how Smurf2 deficiency affects chondrogenic and catabolic gene expressions and Smurf2 and Smurf1 proteins upon TGF-β3 or IL-1β treatment in culture. We found no differences in cortical, subchondral and trabecular bone between WT and MT in young (4 months) and old mice (16–24 months). The articular cartilage and age-related alterations between WT and MT were also similar. However, 2 months following DMM, young MT showed milder OA compared to WT (~70% vs ~30% normal or exhibiting only mild OA cartilage phenotype). The majority of the older WT and MT mice developed moderate/severe OA 2 months after DMM, but a higher subset of aged MT cartilage (27% vs. 9% WT) remained largely normal. Chondrogenic gene expression (Sox9, Col2, Acan) trended higher in MT iMACs than WT with/without TGF-β3 treatment. IL-1β treatment suppressed chondrgenic gene expression, but Sox9 expression in MT remained significantly higher than WT. Smurf2 protein in WT iMACs increased upon TGF-β3 treatment and decreased upon IL-1β treatment in a dose-dependent manner. Smurf1 protein elevated more in MT than WT upon TGF-β3 treatment, suggesting a potential, but very mild compensatory effect. Overall, our data support a role of Smurf2 in regulating OA development but suggest that inhibiting Smurf2 alone may not be sufficient to prevent or consistently mitigate post-traumatic OA across a broad age range.     

Effect of the destruction of the oral and caudal trigeminal nuclei on pain sensitivity in cats

Structural changes of nociceptive response after separate lesions of the oral and caudal trigeminal nuclei were studied in chronic experiments on adult cats. The lesion of the oral nucleus was shown to increase pain response and that of the caudal nucleus--to cause its inhibition. A relationship between the specific and non-specific projection systems of the brain in the development of pain is discussed.     

Distinguishing fibromyalgia from rheumatoid arthritis and systemic lupus in clinical questionnaires: an analysis of the revised Fibromyalgia Impact Questionnaire (FIQR) and its variant, the Symptom Impact Questionnaire (SIQR), along with pain locations

Introduction

The purpose of this study was to explore a data set of patients with fibromyalgia (FM), rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) who completed the Revised Fibromyalgia Impact Questionnaire (FIQR) and its variant, the Symptom Impact Questionnaire (SIQR), for discriminating features that could be used to differentiate FM from RA and SLE in clinical surveys.

Methods

The frequency and means of comparing FM, RA and SLE patients on all pain sites and SIQR variables were calculated. Multiple regression analysis was then conducted to identify the significant pain sites and SIQR predictors of group membership. Thereafter stepwise multiple regression analysis was performed to identify the order of variables in predicting their maximal statistical contribution to group membership. Partial correlations assessed their unique contribution, and, last, two-group discriminant analysis provided a classification table.

Results

The data set contained information on the SIQR and also pain locations in 202 FM, 31 RA and 20 SLE patients. As the SIQR and pain locations did not differ much between the RA and SLE patients, they were grouped together (RA/SLE) to provide a more robust analysis. The combination of eight SIQR items and seven pain sites correctly classified 99% of FM and 90% of RA/SLE patients in a two-group discriminant analysis. The largest reported SIQR differences (FM minus RA/SLE) were seen for the parameters "tenderness to touch," "difficulty cleaning floors" and "discomfort on sitting for 45 minutes." Combining the SIQR and pain locations in a stepwise multiple regression analysis revealed that the seven most important predictors of group membership were mid-lower back pain (29%; 79% vs. 16%), tenderness to touch (11.5%; 6.86 vs. 3.02), neck pain (6.8%; 91% vs. 39%), hand pain (5%; 64% vs. 77%), arm pain (3%; 69% vs. 18%), outer lower back pain (1.7%; 80% vs. 22%) and sitting for 45 minutes (1.4%; 5.56 vs. 1.49).

Conclusions

A combination of two SIQR questions ("tenderness to touch" and "difficulty sitting for 45 minutes") plus pain in the lower back, neck, hands and arms may be useful in the construction of clinical questionnaires designed for patients with musculoskeletal pain. This combination provided the correct diagnosis in 97% of patients, with only 7 of 253 patients misclassified.     

Serum Tryptase Monitoring in Indolent Systemic Mastocytosis: Association with Disease Features and Patient Outcome

Background

Serum baseline tryptase (sBT) is a minor diagnostic criterion for systemic mastocytosis (SM) of undetermined prognostic impact. We monitored sBT levels in indolent SM (ISM) patients and investigated its utility for predicting disease behaviour and outcome.

Methods

In total 74 adult ISM patients who were followed for ≥48 months and received no cytoreductive therapy were retrospectively studied. Patients were classified according to the pattern of evolution of sBT observed.

Results

Overall 16/74 (22%) cases had decreasing sBT levels, 48 (65%) patients showed increasing sBT levels and 10 (13%) patients showed a fluctuating pattern. Patients with significantly increasing sBT (sBT slope ≥0.15) after 48 months of follow-up showed a slightly greater rate of development of diffuse bone sclerosis (13% vs. 2%) and hepatomegaly plus splenomegaly (16% vs. 5%), as well as a significantly greater frequency of multilineage vs. mast cells (MC)-restricted KIT mutation (p = 0.01) together with a greater frequency of cases with progression of ISM to smouldering and aggressive SM (p = 0.03), and a shorter progression-free survival (p = 0.03).

Conclusions

Monitoring of sBT in ISM patients is closely associated with poor prognosis disease features as well as with disease progression, pointing out the need for a closer follow-up in ISM patients with progressively increasing sBT values.     

Single units activities in ventral posterior and posterior group thalamic nuclei during nociceptive and non nociceptive stimulations in the cat.

The purpose of this study was to define, in hyperventilated and unanesthetized cats, the role of the posterior thalamic nuclei in pain mechanisms. Unit activities of these structures were compared to those of the ventro-posterior nucleus during non-noxious (touch, brushing) and noxious stimulations (pinches and intra-arterial injections of bradykinin into the limbs). 135 cells with somatic inputs and clear peripheral excitatory receptive field were studied. The cells driven by noxious stimulations were located in the posterior group nuclei as anatomically defined by Rinvik. These units, preferentially excited from contralateral receptive fields, were localized in POm, POl, suprageniculate nuclei, the magnocellular division of the medial geniculate body (Mgmc) and the ventral part of the lateral posterior nucleus. At this level two groups of units were found: those driven only by noxious stimulations and those driven by both noxious and non-noxious stimulations. On contrast, cells recorded at the levels of the VPm and VPl were not activated by noxious stimuli. These results emphasize the role of the posterior thalamic nuclei in pain processing.     

Severe malaria in Burkina Faso: urban and rural environment

The age distribution and the clinical patterns of severe malaria (SM) were compared in patients from urban areas characterized by relatively low transmission, and from rural areas where the mean inoculation rates are at least twenty fold higher. The mean age of the urban and rural patients was 4.8 +/- 3.0 and 2.2 +/- 1.9 respectively (p < 0.000). The prevalence of coma was higher in the urban subsample (53.6 vs 28.9%, p < 0.000) while that of severe anemia (hemoglobin < 5 g/dl) was higher in rural patients (47.4 vs 14.8%, p < 0.000). Our data, in line with previous results obtained comparing rural areas characterized by different inoculation rates, show that the epidemiological context influences the clinical presentation of SM.     

Role of the caudate nucleus in the development of evoked synchronized activity

Synchronized activity (spindles, augmentation response) evoked by stimulation of thalamic nonspecific, association, and specific nuclei was investigated in chronic experiments on 11 cats before and after successive destruction of the caudate nuclei. After destruction of the caudate nuclei the duration of spindle activity in the frontal cortex and subcortical formations (thalamic nuclei, globus pallidus, putamen) was reduced to only three or four oscillations. In the subcortical nuclei its amplitude fell significantly (by 50±10%); in the cortex the decrease in amplitude was smaller and in some cases was not significant. Different changes were observed in the amplitude of the augmentation response, depending on where it was recorded. In the subcortical formations it was considerably and persistently reduced (by 50±10%); in the cortex these changes were unstable in character. Unilateral destruction of the caudate nucleus inhibited synchronized activity evoked by stimulation of the thalamic nuclei on the side of the operation only. Destruction of the basal ganglia (caudate nucleus, globus pallidus, entopeduncular nucleus, and putamen) did not prevent the appearance of synchronized activity; just as after isolated destruction of the caudate nucleus, after this operation synchronized activity was simply reduced in duration and amplitude. It is suggested that the caudate nucleus exerts an ipsilateral facilitatory influence on the nonspecific system of the thalamus during the development of evoked synchronized activity.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 9, No. 3, pp. 239–248, May–June, 1977.     

A radioautographic and immunocytochemical study of the GABA systems of the habenula complex in the rat

Radioautography of [³H]GABA accumulation and immunocytochemistry of glutamate decarboxylase have been used to study anatomically and morphologically the GABA system of the rat habenular (Hb) complex. Radioautographic visualisation of GABA specific neurons show a very high innervation of the complex including both stria medullaris (SM), the habenular commissure and the periventricular thalamic fibers (FPVT). A massive labeled fiber system in the SM appears to divide into two branches when it reaches the Hb nuclei: a part of fibers continue their course dorsally to the nuclei up to the habenular commissure; other fibers enter the Hb lateralis or run along the ventral Hb medialis at the level of FPVT. The staining is markedly diminished in the entire complex in response to SM lesions. In the Hb lateralis, the radioautographic-positive reaction is mainly bound to labeled fibers or axonal varicosities. However GAD immunocytochemistry reveals some GAD-positive cell bodies in the ventro-median portion of the nucleus. In the Hb medialis the radioautographic and immunocytochemical staining is observed in the neuropile between the unlabeled large cell bodies. In the subependymal layer bundles of processes are strongly labeled and form a continual strain behind the unlabeled ependymocytes. Three types of reactive terminals have been differentiated based on size and shape of vesicles. Some of them are exclusively characterized by clear round vesicles and probably have their origin in the septum. Others contain clear vesicles and some large dense-cored vesicles and disappear after mesencephalic Raphe lesions or 5,7-dihydroxytryptamine treatment. They could correspond to terminals of raphe neurons with a double potentiality GABA and 5HT. The last exhibit mainly a dense population of large dark-cored granules similar to the ones found in neurosecretory nerve endings. However numerous fibers morphologically similar to the reactive fibers are unlabeled.