A longitudinal molecular surveillance study of human polyomavirus viremia in heart, kidney, liver, and pancreas transplant patients

In this study of 263 heart, kidney, liver, and pancreas transplant patients, BK virus (BKV) and JC virus (JCV) DNAemia were observed most commonly in kidney and/or pancreas transplant patients (26%), although they were also observed, to a lesser extent, in heart (7%) and liver (4%) transplant patients. The majority of episodes of polyomavirus DNAemia were subclinical, although, in some cases, BKV DNAemia was associated with kidney rejection, and JCV DNAemia was accompanied by nonspecific symptoms. Hence, BKV and JCV DNAemia are not uncommon during the first year after kidney, heart, liver, and pancreas transplantation, and they could be associated with certain clinical syndromes in transplant patients.     

Dysglycemias in pregnancy: from diagnosis to treatment. Brazilian consensus statement

There is an urgent need to find consensus on screening, diagnosing and treating all degrees of DYSGLYCEMIA that may occur during pregnancies in Brazil, considering that many cases of DYSGLYCEMIA in pregnant women are currently not diagnosed, leading to maternal and fetal complications. For this reason the Brazilian Diabetes Society (SBD) and the Brazilian Federation of Gynecology and Obstetrics Societies (FEBRASGO), got together to introduce this proposal. We present here a joint consensus regarding the standardization of clinical management for pregnant women with any degree of Dysglycemia, on the basis of current information, to improve medical assistance and to avoid related complications of Dysglycemia in pregnancy to the mother and the fetus. This consensus aims to standardize the diagnosis among general practitioners, endocrinologists and obstetricians allowing the dissemination of information in basic health units, public and private services, that are responsible for screening, diagnosing and treating disglycemic pregnant patients.     

Abnormal reliance on object structure in apraxics' learning of novel object-related actions.

We assessed the prediction that object structural cues could benefit the learning of object-action relationships in ideomotor apraxia (IMA). A total of 15 patients with left-hemisphere stroke, 11 of whom exhibited IMA, and 10 healthy subjects were trained to match novel gestures to novel tool pictures that were either High- or Low-Afforded by their associated tools. Learning was assessed with recognition and production tests. Only IMA patients demonstrated better recognition of High- than Low-Afforded gestures, and their recognition of High-Afforded gestures was statistically comparable to the other groups. This finding suggests that apraxics may rely abnormally on object structure when learning to associate novel gestures and tools. Finally, the "affordance benefit" was associated with relative sparing of structures in the dorsal visual processing stream. These data are consistent with the proposal that two routes may mediate skilled action, one specialized for stored information, and the other responsive to object structure, and that deficient gesture learning may be compensated by "bootstrapping" intact dorsal stream coding of action.     

Biological and immunological properties of the nerve growth factor from bovine seminal plasma: comparison with the properties of mouse nerve growth factor

The biological activities of Nerve Growth Factor (NGF) purified from bovine seminal plasma have been compared with those of NGF from mouse submandibular glands in a variety of systems: maintenance of survival in vitro and stimulation of nerve fibre outgrowth from sensory, sympathetic and parasympathetic neurons of the embryonic chick; maintenance of survival in vitro, stimulation of nerve fibre outgrowth and specific induction of tyrosine hydroxylase in neonatal rat sympathetic neurons; stimulation of nerve fibre outgrowth and cellular hypertrophy and specific induction of choline acetyltransferase in pheochromocytoma PC12 cells; induction of tyrosine hydroxylase in bovine adrenal medullary cells; and stimulation of nerve fibre outgrowth from expiants of goldfish retinae. In all cases, the two NGFs had the same effects qualitatively and quantitatively, and with identical dose-dependencies. The results indicate that the wide range of biological effects and target cells delineated in detail for mouse NGF can justifiably be attributed to other NGF proteins, and that they are not exclusively restricted to the mouse NGF molecule. Furthermore, as bovine NGF is free of the renin contaminants so difficult to remove from mouse NGF, the above biological activities can truly be assigned to the NGF molecule.Immunologically, however, mouse and bovine NGFs differ substantially. This is demonstrated by the relatively poor ability of antisera against bovine NGF to inhibit the activity of mouse NGF in vitro, and by the incomplete nature of the immunosympathectomy caused in rats by treatment with antisera to bovine NGF, in contrast to the extensive immunosympathectomy caused in these animals by the administration of comparable quantities of antisera against mouse NGF.Clearly, the biochemical features of the NGF molecules responsible for their biological effectiveness and for their predominant antigenic properties are different.     

The neurotrophin receptor p75(NTR): novel functions and implications for diseases of the nervous system

Neurotrophins have long been known to promote the survival and differentiation of vertebrate neurons. However, these growth factors can also induce cell death through the p75 neurotrophin receptor (p75(NTR)), a member of the tumor necrosis factor receptor superfamily. Consistent with a function in controlling the survival and process formation of neurons, p75(NTR) is mainly expressed during early neuronal development. In the adult, p75(NTR) is re-expressed in various pathological conditions, including epilepsy, axotomy and neurodegeneration. Potentially toxic peptides, including the amyloid beta- (Abeta-) peptide that accumulates in Alzheimer's disease, are ligands for p75(NTR). Recent work also implicates p75(NTR) in the regulation of both synaptic transmission and axonal elongation. It associates with the Nogo receptor, a binding protein for axonal growth inhibitors, and appears to be the transducing subunit of this receptor complex.     

Interim and temporary restoration of teeth during endodontic treatment

One of the main aims of endodontic treatment is to eliminate micro-organisms from within the root canal system. A further aim is to prevent the ingress of any further bacteria during and after treatment. These aims are usually achieved by various means and stages throughout the treatment process. Endodontic treatment is usually performed on teeth that have lost the integrity of the external coronal tooth structure which has allowed bacteria to enter the tooth and ultimately reach the pulp space. Further opening of the tooth occurs when an endodontic access cavity is made to allow treatment to be performed. Hence, there will always be a need for interim and temporary restoration of teeth undergoing endodontic treatment. Many different materials and techniques have been proposed, and these proposals have been based on many research reports. The purposes of this article are to review the literature regarding the use of interim and temporary restorations, and to provide recommendations regarding such restorations for clinicians to follow when providing endodontic treatment.     

Experiences of the first 493 unrelated marrow donors in the National Marrow Donor Program

More than 410,000 people participated in the National Marrow Donor Program (NMDP) as of October 1, 1991, and more than 850 volunteers had donated marrow. While the incidence of serious morbidity as a result of bone marrow donation is rare, the incidence of lesser complications and the long-term consequences of marrow donation are not known. To determine the incidence of donor complications and measure the recovery time of volunteer, unrelated marrow donors, we analyzed the results of surveys of the first 493 persons who donated marrow through the NMDP. The marrows were collected at 42 centers. The median age of the donors was 37.9 years (range 19.1 to 55.6 years). The median volume of marrow collected was 1,050 mL (range 180 to 2,983 mL). Autologous red blood cells were transfused to 89.8% (439) of donors but only 0.6% (3) of donors received allogeneic blood. Acute complications related to the collection procedure occurred in 5.9% of donors; but a serious complication, apnea during anesthesia, occurred in only one donor. When donors were questioned approximately 2 days following discharge from their hospitalization, most donors described symptoms related to the collection; 74.8% experienced tiredness, 67.8% experienced pain at the marrow collection site, and 51.6% of the donors experienced low back pain. Donors were surveyed repeatedly until they felt that they had recovered completely. Mean recovery time was 15.8 days; however, 42 (10%) donors felt that it took them > or = 30 days to recover fully. The duration of the marrow collection procedure and duration of anesthesia both positively correlated with donor pain and/or fatigue following the collection; but the duration of the collection procedure had the highest correlation with post-collection pain and fatigue. The volume of marrow collected per unit of donor weight was more weakly correlated with donor pain and/or fatigue than the anesthesia and collection times. When multivariate analysis was used to analyze the correlation between donor recovery time and these variables, only the duration of the collection was found to correlate significantly with donor recovery time (P = .001). This analysis demonstrates that marrow donation is well tolerated with few complications. To decrease further the incidence of donor discomfort and recovery time following donation, the duration of the collection procedure, and probably the duration of anesthesia, and the volume of marrow collected, should be kept to a minimum.     

Brain-derived neurotrophic factor supports the survival of cultured rat retinal ganglion cells

Brain-derived neurotrophic factor (BDNF) is a small, basic protein purified from the mammalian brain that has been shown previously to support the survival of cultured spinal sensory neurons (Barde et al., 1982). In current studies, BDNF was tested for its ability to support the survival of cultured CNS cells isolated from the perinatal rat retina. Both immunofluorescent labeling of Thy-1 and prior retrograde labeling with HRP were used as retinal ganglion cell markers in vitro. With embryonic day (E) 17 retinas, it was found that BDNF allowed the survival of a small subpopulation of neurons (about 7% of the cells plated at this age) identified by the immunofluorescent labeling of Thy-1. No detectable effects were seen when either the total number of cells or the number of tetanus toxin-positive neurons was measured. BDNF also had an effect on cultured neurons retrogradely labeled after HRP injections in the superior colliculi of neonatal rats. The BDNF-responsive population was therefore detected only in retinal cultures with specific markers and identified as consisting of retinal ganglion cells. These cells could be enriched about 80-fold by density gradient centrifugation, and purified ganglion cell cultures were shown to be responsive to BDNF. Whereas with E17 retinas, the number of surviving Thy-1 positive neurons could be kept constant for at least 4 d, the survival of postnatal neurons was only transiently increased by BDNF. We conclude that in the retina, BDNF affects only the survival of ganglion cells in vitro by a direct action on these cells. The results are discussed in terms of target-derived neurotrophic support during development.