Distribution patterns of phosphorylated Thr 3 and Thr 32 of histone H3 in plant mitosis and meiosis

Cell cycle dependent phosphorylation of conserved N-terminal tail residues of histone H3 has been described in both animal and plant cells. Through cytogenetic approaches using different plant species we show a detailed description of distribution patterns of phosphorylated histone H3 at either threonine 3 or threonine 32 in mitosis and meiosis. In meristematic cells of the large genome species Secale cereale, Vicia faba and Hordeum vulgare we have found that phosphorylation of both threonine residues begins in prophase, and dephosphorylation occurs in late anaphase. However, in the small genome species Arabidopsis thaliana dephosphorylation occurs at anaphase. In the first division of meiosis of species with large genomes phosphorylation of histone H3 at either threonine 3 or threonine 32 is seen first in diakinesis and extends to anaphase I, whereas in the second division these post-translational modifications are visible at metaphase II through anaphase II. While in A. thaliana dephosphorylation takes place at anaphase I and II. In all species analysed phosphorylated H3 at either threonine 3 or threonine 32 are distributed along the entire length of chromosomes during mitotic metaphase and metaphase I. In the second meiotic division threonine 3 phosphorylation is restricted to the pericentromeric domain, while phosphorylation of threonine 32 is widespread along chromosome arms of all species analysed.

Cadmium induces changes in sucrose partitioning, invertase activities, and membrane functionality in roots of Rangpur lime (Citrus limonia L. Osbeck)

Cadmium (Cd) uptake effects on sucrose content, invertase activities, and plasma membrane functionality were investigated in Rangpur lime roots ( CITRUS LIMONIA L. Osbeck). Cadmium accumulation was significant in roots but not in shoots and leaves. Cadmium produced significant reduction in roots DW and increment in WC. Leaves and shoots did not show significant differences on both parameters. Sucrose content was higher in control roots than in Cd-exposed ones. Apoplastic sucrose content was much higher in Cd-exposed roots than in control ones. Cd-exposed roots showed a significant decrease in both cell wall-bound and cytoplasmic (neutral) invertase activities; while the vacuolar isoform did not show any change. Alterations in lipid composition and membrane fluidity of Cd-exposed roots were also observed. In Cd-exposed roots phospholipid and glycolipid contents decreased about 50 %, while sterols content was reduced about 22 %. Proton extrusion was inhibited by Cd. Lipid peroxidation and proton extrusion inhibition were also detected by histochemical analysis. This work's findings demonstrate that Cd affects sucrose partitioning and invertase activities in apoplastic and symplastic regions in Rangpur lime roots as well as the plasma membrane functionality and H (+)-ATPase activity.

Clinical and biochemical study of 28 patients with mucopolysaccharidosis type VI

This paper presents data collected by a Brazilian center in a multinational multicenter observational study of patients with mucopolysaccharidosis type VI (MPS VI), aiming at determining the epidemiological, clinical, and biochemical profile of these patients. Twenty-eight south-American patients with MPS VI were evaluated through medical interview, physical exam, echocardiogram, electrocardiogram, ophthalmologic evaluation, quantification of glycosaminoglycans (GAGs) in urine, and measurement of the activity of N-acetylgalactosamine-4-sulfatase (ARSB) in leukocytes. 92.9% of patients were Brazilian. Mean age at diagnosis and at evaluation was 48.4 months and 97.1 months, respectively. 88% of patients had onset of symptomatology before the age of 36 months. Consanguinity was reported by 27% of the families. Mean weight and height at birth were 3.481 kg and 51.3 cm, respectively. The most frequently reported clinical manifestations were short stature, corneal clouding, coarse facial features, joint contractures, and claw hands. All patients presented with echocardiogram changes as well as corneal clouding. Mean ARSB activity in leukocytes was 5.4 nmoles/h/mg protein (reference values: 72-174), and urinary excretion of GAGs was on average 7.9 times higher than normal. The number of clinical manifestations did not show a significant correlation with the levels of urinary GAGs nor with the ARSB activity. Also, no significant correlation was found between the levels of urinary GAGs and the ARSB activity. It was concluded that MPS VI has high morbidity and that, when compared with data published in the literature, patients in our study were diagnosed later and presented with a higher frequency of cardiological findings.

Subcortical nodular heterotopia: a functional MRI and somatosensory evoked potentials study

Subcortical nodular heterotopia (SNH) associated with refractory epilepsy may be surgically treated, and a positive outcome can be expected following the complete excision of the malformed tissue. Recent functional neuroimaging studies have suggested the possible functional relevance of cerebral malformations, and may make it possible to improve presurgical planning, thus allowing extended resections and minimising post-operative deficits. We here report the case of a 19-year-old man with epilepsy and a giant SNH associated with diffused abnormal gyrations of the right temporal-parietal regions. Cortical functional organisation was investigated by means of functional magnetic resonance imaging (MRI) during sensory and motor tasks, and somatosensory evoked potentials. The results revealed enlarged and displaced motor and sensory cortical areas with heterotopic tissue functional activation. The relevance of these findings is discussed in the light of the possible surgical treatment of drug-refractory epilepsy associated with cerebral malformations: surgical treatment based on conventional MRI studies alone, without taking the functional nature of dysplastic tissues into account, may lead to considerable side effects.

Auditory capacities in Middle Pleistocene humans from the Sierra de Atapuerca in Spain

Human hearing differs from that of chimpanzees and most other anthropoids in maintaining a relatively high sensitivity from 2 kHz up to 4 kHz, a region that contains relevant acoustic information in spoken language. Knowledge of the auditory capacities in human fossil ancestors could greatly enhance the understanding of when this human pattern emerged during the course of our evolutionary history. Here we use a comprehensive physical model to analyze the influence of skeletal structures on the acoustic filtering of the outer and middle ears in five fossil human specimens from the Middle Pleistocene site of the Sima de los Huesos in the Sierra de Atapuerca of Spain. Our results show that the skeletal anatomy in these hominids is compatible with a human-like pattern of sound power transmission through the outer and middle ear at frequencies up to 5 kHz, suggesting that they already had auditory capacities similar to those of living humans in this frequency range.

Non-linear filtering of ultrasonic signals using neural networks

Structure noise from inhomogeneous micro-structures makes the detection of flaws present in highly scattering materials difficult. Several techniques have been applied to improve the signal-to-noise ratio (SNR) in order to make flaw detection easier. Linear filtering does not provide good results because both structure noise and flaw signal concentrate energy in the same frequency band. Non-linear filtering can be used to reduce the structure noise of ultrasonic signals. Therefore, neural networks are applied in this work for this purpose. In order to use neural networks for non-linear filtering, dynamic structures must be applied. The easiest way to implement a neural network with the capability of processing temporal patterns is to consider them spatial ones, applying the signal into a tapped delay line of finite extension, that is the input of a static neural network (for example, a multi-layer perceptron). In this work, a dynamic neural network has been built to filter ultrasonic signals with structure noise, and has been trained with the real-time back-propagation algorithm, using as inputs 3000 synthetic ultrasonic signals of 896 samples each. Target signals for training are the same as the ones used as inputs but without noise. The neural network is trained in order to generate as output the target signal when the noisy input one is applied. For testing the performance of the non-linear filter, a new set of 500 noisy signals has been used. The SNR improvement is about 6 dB average. The results show that this non-linear filtering method is quite useful as pre-processing stage in flaw detection systems.

Ultrasonic flaw detection using radial basis function networks (RBFNs)

Ultrasonic flaw detection has been studied many times in the literature. Schemes based on thresholding after a previous matched filter use to be the best solution, but results obtained with this method are only satisfactory when scattering and attenuation are not considered. In this paper, we propose an alternative solution to thresholding detection method. We deal with the usage of different flaw detection methods comparing them with the proposed one. The experiment tries to determinate whether a given ultrasonic signal contains a flaw echo or not. Starting with a set of 24,000 patterns with 750 samples each one, two subsets are defined for the experiments. The first one, the training set, is used to obtain the detection parameters of the different methods, and the second one is used to test the performance of them. The proposed method is based on radial basis functions networks, one of the most powerful neural network techniques. This signal processing technique tries to find the optimal decision criterion. Comparing this method with thresholding based ones, an improvement over 25-30% is obtained, depending on the probability of false alarm. So our new method is a good alternative to flaw detection problem.

[Collaborative study on peritoneal dialysis (PD) as first dialysis treatment in an Italian region: 1994-2000]

BACKGROUND

In Lazio, only about 5% of uremic patients are on peritoneal dialysis (PD). The present study focuses on the parameters of PD selection, the treatment schedules, and the clinical outcomes of PD patients in the nine public facilities offering a PD program. A cohort of 249 first-time PD patients, from July 1, 1994 to December 31, 2000, was retrospectively considered.

METHODS

For the enrollment of the patients, the Regional Dialysis Registry databank was consulted. On December 31, 2000, a systematic review of patient charts was performed to extract the reasons for the PD choice, details of PD schedule, peritonitis episodes, reasons for drop-out, and patient survival rates. In regard to technique success-defined as the probability of having a patient alive on PD-change of modality and death were considered as final events. In regard to patient survival, only death, even in the first 2 months after a shift to hemodialysis, was considered the end point.

RESULT

The main PD selection reasons were patient and/or nephrologist preference in 90% of cases. One-hundred eighty-nine patients (76%) had been started on CAPD. During the follow-up, 38.2% dialysis schedules had been modified at least once. At the end of follow-up, 41.2% patients were on APD. The peritonitis rate was one episode per 30 patient-months (1 per 27 patient-months in CAPD; 1 per 37 patient-months in APD; p = 0.08). The technique success rate was 66.3% after 2 years and 49.8% after 3 years. The patient survival rate was 81.1% after 2 years and 68.7% after 3 years.

CONCLUSIONS

Patients chose PD as a first dialysis treatment mainly because of reasons unrelated to their clinical status. The technique's success, patient mortality rates, and the peritonitis rate do not explain the low PD diffusion in the region. The peritonitis rate meets the target criteria for excellence recommended by the Italian Society of Nephrology. The observed outcomes may have been favored by the selection of motivated patients and by the increased use of APD.

A fMRI study of word retrieval in aphasia

The neural mechanisms underlying recovery of cognitive functions are incompletely understood. Aim of this study was to assess, using functional magnetic resonance (fMRI), the pattern of brain activity during covert word retrieval to letter and semantic cues in five aphasic patients after stroke, in order to assess the modifications of brain function which may be related to recovery. Four out of five patients had undergone language recovery, according to standard testing, after at least 6 months of rehabilitation. The cerebral activation of each patient was evaluated and compared with the activation pattern of normal controls studied with the same fMRI paradigm. In the patients, the pattern of brain activation was influenced by the site and extent of the lesion, by the degree of recovery of language, as reflected by task performance outside the scanner, and by task requirements. In the case of word retrieval to letter cues, a good performance was directly related to the activation in Broca's area, or in the right-sided homologue. On the other hand, in the case of semantic fluency, the relationship between performance level and activation was less clear-cut, because of extensive recruitment of frontal areas in patients with defective performance. These findings suggest that the performance in letter fluency is dependent on the integrity of the left inferior frontal cortex, with the participation of the homologous right hemispheric region when the left inferior frontal cortex is entirely of partially damaged. Semantic fluency, which engages the distributed network of semantic memory, is also associated with more extensive patterns of cerebral activation, which however appear to reflect retrieval effort rather than retrieval success.

Recovery of third nerve palsy after endovascular packing of internal carotid-posterior communicating artery aneurysms

SUMMARY

Endovascular packing of intracranial aneurysm with preservation of the parent vessel has become in many cases a valid alternative to surgical clipping. Regression of oculomotor disorders after clipping of internal carotid-posterior communicating artery (ICA-PCoA) aneurysms has been well assessed. This report focuses on the reversal of third nerve palsy after endovascular packing of ICA-PCoA aneurysms. To this end, clinical appearances, neuroradiological features, and endovascular interventional procedures of six treated patient are reported and discussed in the light of the very few previous case observations found in the literature. Results indicate that endovascular packing of ICA-PCoA aneurysms may produce effective recovery of correlated third nerve dysfunction.

Retinoids in breast cancer prevention and treatment. A review of the literature

During the last three decades, research focused on cancer treatment has led to the development of many cytotoxic agents. Despite the fact that these efforts have significantly improved the prognosis of certain malignancies such as some lymphomas, leukemias and testicular carcinomas, other tumors such as ovarian, lung and metastatic breast cancer are still associated with a poor prognosis. An innovative approach has recently emerged, thanks to a better understanding of tumor cell biology and many efforts are aimed at finding compounds capable of restoring a more differentiated phenotype to tumor cells, thereby reducing the tumor's aggressiveness and ultimately reverting it to its normal counterpart [1, 2]. Retinoids are the prototype of this new therapeutical approach called "differentiation therapy".

Identification of novel porcine endogenous betaretrovirus sequences in miniature swine

PCR amplification of genomic DNA from miniature swine peripheral blood lymphocytes, using primers corresponding to highly conserved regions of the polymerase (pol) gene, allowed the identification of two novel porcine endogenous retrovirus (PERV) sequences, PMSN-1 and PMSN-4. Phylogenetic analyses of the nucleotide sequences of PMSN-1 and PMSN-4 revealed them to be most closely related to betaretroviruses. The identification of PERVs belonging to the Betaretrovirus genus shows that endogenous retroviruses of this family are more broadly represented in mammalian species than previously appreciated. Both sequences contained inactivating mutations, implying that these particular loci are defective. However, Southern blot analysis showed additional copies of closely related proviruses in the miniature swine genome. Analyses of fetal and adult miniature swine tissues revealed a broad mRNA expression pattern of both PMSN-1 and PMSN-4. The most abundant expression was detected in whole bone marrow c-kit(+) (CD117(+)) progenitor bone marrow cells, fetal liver, salivary gland, and thymus. It appears unlikely that functional loci encoding these novel PERV sequences exist, but this remains to be established. The betaretrovirus sequences described in this report will allow such investigations to be actively pursued.

Validating facemask use for gas exchange analysis in patients with congestive heart failure

PURPOSE

Functional limitation, often associated with congestive heart failure (CHF), is most accurately assessed with measurement of peak VO2 (VO2peak) during exercise testing. VO2peak strongly predicts survival in CHF patients and is used to triage patients for cardiac transplantation. However, the traditional mouthpiece/noseclip equipment used for gas exchange analysis is often cumbersome and uncomfortable. Several alternative facemask designs tested previously in healthy cohorts were inferior to the mouthpiece for measuring VO2peak. In this study, a series of facemasks designed specifically for VO2peak testing (Hans-Rudolph) was employed. Although previously validated in healthy young adults, this apparatus has not been validated in patients with severe CHF.

METHODS

The Hans-Rudolph facemasks were compared with the mouthpiece apparatus in 30 patients with severe CHF. Each subject completed a cardiopulmonary exercise test with each device. Twelve subjects were randomized to evaluate a possible training effect. To enhance recruitment, 18 additional subjects were recruited after they had completed a test with the mouthpiece.

RESULTS

There was no evidence of a training effect and no differences in gas exchange measurements were found between the two devices. The weight-adjusted VO2peak measurements were 17.1 +/- 5.3 ml O2/kg/min for the mouthpiece group and 17.3 +/- 5.6 ml O2/kg/min for the mask group (P = 0.54).

CONCLUSIONS

The facemask was shown to be equivalent to the mouthpiece for measuring VO2peak in CHF patients. Concerns of hypoventilation and decreased VO2peak associated with previous facemask designs were not substantiated. Since successful exercise testing depends on maximal exertion, providing a choice of equipment may facilitate cooperation without sacrificing accuracy.

Renal hemodynamic response to maximal vasodilating stimulus in healthy older subjects

BACKGROUND

It is still unclear whether age per se is associated with preservation of renal functional reserve, that is, of the increase in glomerular filtration rate (GFR) induced by appropriate vasodilating stimulus.

METHODS

To gain insights into this issue, we evaluated the renal response to a maximal vasodilating stimulus, represented by the combined infusion of mixed amino acid solution (AA) and dopamine at renal dose (D), in 10 young subjects (median age of 30 years, range of 19 to 32) and in 11 subjects of older age (median age of 67 years, range of 65 to 76). Two further age-matched groups of young (N = 15) and older (N = 11) living kidney donors underwent renal needle biopsy immediately before nephrectomy to perform semiquantitative scoring (0 to 3) of arteriosclerosis in intrarenal arteries. All of the study subjects were nonsmokers with healthy status proven by extensive diagnostic evaluation excluding any risk factor of renal dysfunction.

RESULTS

Basal renal plasma flow (RPF) and GFR were proportionally lower in older subjects (RPF, 361 +/- 29 vs. 618 +/- 34 mL/min/1.73 m(2), P < 0.001; GFR, 79 +/- 4 vs. 127 +/- 5.8 mL/min/1.73 m(2), P < 0.001). After AA + D, a significant increase of RPF and GFR was observed in both groups, but the older subjects exhibited a smaller percentage increment (RPF, 25.5 +/- 4.8 vs. 42.4 +/- 5.8, P < 0.05; GFR, 19.6 +/- 5.7 vs. + 33.8 +/- 6.4, P < 0.05). Furthermore, the maximal vasodilating stimulus was not able to restore renal hemodynamics in older subjects to the level measured in young controls at baseline. Renal vascular resistances were higher (P < 0.05) in the older subjects both at baseline (0.19 +/- 0.02 vs. 0.09 +/- 0.004 mm Hg/mL/min) and after AA + D (0.14 +/- 0.01 vs. 0.06 +/- 0.004). Light microscopy examination detected the presence of a greater degree of arteriosclerosis at the level of interlobular and arcuate arteries (0.89 +/- 0.15 vs. 0.45 +/- 0.08) and interstitial fibrosis/tubular atrophy (1.18 +/- 0.13 vs. 0.53 +/- 0.13) in older than in young subjects.

CONCLUSIONS

Therefore, aging has adverse effects on renal function despite the absence of any risk factor for renal disease, including chronic smoking: (1) GFR and RPF are lower, and (2) the renal response to maximal vasodilating stimulus is impaired. These aging-related alterations of renal hemodynamics are possibly due to organic lesions in renal vasculature.

Integrative medicine: a paradigm shift in medical education and practice

The use of alternative/complementary medicine has been increasing considerably. Conventional medicine must begin to address issues related to the use, safety, regulation, research and education of alternative/complementary medicine. Integrative medicine combines conventional medicine and alternative complementary practices. Integrative medicine is an innovative approach to medicine and medical education. It involves the understanding of the interaction of the mind, body and spirit and how to interpret this relationship in the dynamics of health and disease. Integrative medicine shifts the orientation of the medical practice from disease based approach to a healing based approach. It does not reject conventional medicine nor uncritically accepts unconventional practices. Integrative medicine is an effective, more fulfilling human approach to medicine based on the benefit of the patient by following good medicine practices in a scientific manner.

Embolisation of Orbital Varix via the Superficial Temporal Vein

SUMMARY

A case of orbital varix is presented, in which the lesion was successfully treated by means of embolisation with Guglielmi detachable coils, via the superficial temporal vein. Reports of endovascular treatment via transvenous route of orbital varix are lacking, only one case having previously been presented in the literature.We stress endovascular management for such an entity.

Heritability of the maternal meiotic drive system linked to Om and high-resolution mapping of the Responder locus in mouse

Matings between (C57BL/6 x DDK)F(1) females and C57BL/6 males result in a significant excess of offspring inheriting maternal DDK alleles in the central region of mouse chromosome 11 due to meiotic drive at the second meiotic division. We have shown previously that the locus subject to selection is in the vicinity of D11Mit66, a marker closely linked to the Om locus that controls the preimplantation embryo-lethal phenotype known as the "DDK syndrome." We have also shown that observation of meiotic drive in this system depends upon the genotype of the sire. Here we show that females that are heterozygous at Om retain the meiotic drive phenotype and define a 0.32-cM candidate interval for the Responder locus in this drive system. In addition, analysis of the inheritance of alleles at Om among the offspring of F(1) intercrosses indicates that the effect of the sire is determined by the sperm genotype at Om or a locus linked to Om.

Sex-of-offspring-specific transmission ratio distortion on mouse chromosome X

During our study of the DDK syndrome, we observed sex ratio distortion in favor of males among the offspring of F(1) backcrosses between the C57BL/6 and DDK strains. We also observed significant and reproducible transmission ratio distortion in favor of the inheritance of DDK alleles at loci on chromosome X among female offspring but not among male offspring in (C57BL/6 x DDK)F(1) x C57BL/6 and (C57BL/6-Pgk1(a) x DDK)F(1) x C57BL/6 backcrosses. The observed transmission ratio distortion is maximum at DXMit210 in the central region of chromosome X and decreases progressively at proximal and distal loci, in a manner consistent with the predictions of a single distorted locus model. DXMit210 is closely linked to two distortion-controlling loci (Dcsx1 and Dcsx2) described previously in interspecific backcrosses. Our analysis suggests that the female-offspring-specific transmission ratio distortion we observe is likely to be the result of the death of embryos of particular genotypic combinations. In addition, we confirm the previous suggestion that the transmission ratio distortion observed on chromosome X in interspecific backcrosses is also the result of loss of embryos.

Chromosome aberrations induced by aphidicolin

The expression of aphidicolin (apc)-produced common fragile sites and chromosome aberrations observed 24 h after apc treatment was studied in a normal individual. The chromosome lesions (gaps and breaks) induced by apc are expressed as full chromosomal aberrations in later cell divisions. We compared chromosome rearrangements or anomalies induced by apc (detected in 45.4% of metaphases analyzed) with those present in human neoplasia or involved in primate evolution. We found that 55.7% of deletions observed in our study coincided with deletions implicated in several types of neoplasia. However, none of 49 translocations observed in our study coincided with those described as recurrently associated with human neoplasia, probably due to their unbalanced nature. When chromosome aberrations detected in our study (only deletions and inversions were taken into account) were compared to those involved in primate evolution, we found a low rate of coincidence. The low coincidence between chromosome alterations in neoplasia and evolution and those observed in our study could be explained because we analyzed chromosome alterations that had not been selected, whereas those present in chromosome evolution and in neoplasia had been subjected to a selection process.