Multisensory exploration and object individuation in infancy.

Recent research indicates that by 4.5 months, infants use shape and size information as the basis for individuating objects but that it is not until 11.5 months that they use color information for this purpose. The present experiments investigated the extent to which infants' sensitivity to color information could be increased through select experiences. Five experiments were conducted with 10.5- and 9.5-month-olds. The results revealed that multimodal (visual and tactile), but not unimodal (visual only), exploration of the objects prior to the individuation task increased 10.5-month-olds' sensitivity to color differences. These results suggest that multisensory experience with objects facilitates infants' use of color information when individuating objects. In contrast, 9.5-month-olds did not benefit from the multisensory procedure; possible explanations for this finding are explored. Together, these results reveal how an everyday experience--combined visual and tactile exploration of objects--can promote infants' use of color information as the basis for individuating objects. More broadly, these results shed light on the nature of infants' object representations and the cognitive mechanisms that support infants' changing sensitivity to color differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reexpansion pulmonary edema

Reexpansion pulmonary edema is a rare complication attending the rapid reexpansion of a chronically collapsed lung, such as occurs after evacuation of a large amount of air or fluid from the pleural space. The condition usually appears unexpectedly and dramatically-immediately or within 1 h in 64% of patients and within 24 h in the remainder. The clinical manifestations are varied; they range from roentgenographic findings alone in asymptomatic patients to severe cardiorespiratory insufficiency. The radiographic evidence of reexpansion pulmonary edema is a unilateral alveolar filling pattern, seen within a few hours of reexpansion of the lung. The edema may progress for 24-48 h and persist for 4-5 days. Human data on the pathophysiology of reexpansion pulmonary edema derive from small series of patients, case reports, and reviews of the literature. On the other hand, a larger body of data exists on experimental reexpansion pulmonary edema in cats, monkeys, rabbits, sheep, and goats. This review examines the clinical and experimental evidence for reexpansion pulmonary edema. In addition, we detail the historical background, clinical setting, treatment, and outcome of reexpansion pulmonary edema.     

P2X3 is expressed by DRG neurons that terminate in inner lamina II

The P2X3 receptor subunit, a member of the P2X family of ATP-gated ion channels, is almost exclusively localized in sensory neurons. In the present study, we sought to gain insight into the role of P2X3 and P2X3-containing neurons in sensory transmission, using immunohistochemical approaches. In rat dorsal root ganglia (DRG), P2X3-immunoreactivity (-ir) was observed in small- and medium-sized neurons. Approximately 40% of DRG neuronal profiles in normal rats contained P2X3-ir. In rats that had received neonatal capsaicin treatment, the number of P2X3-positive neurons was decreased by approximately 70%. Analysis of the colocalization of P2X3-ir with cytochemical markers of DRG neurons indicated that approximately 94% of the P2X3-positive neuronal profiles were labelled by isolectin B4 from Bandeiraea simplicifolia, while only 3% contained substance P-ir, and 7% contained somatostatin-ir. In dorsal horn of rat spinal cord, P2X3-ir was observed in the inner portion of lamina II and was reduced subsequent to dorsal rhizotomy, as well as subsequent to neonatal capsaicin treatment. Finally, P2X3-ir accumulated proximal to the site of sciatic nerve ligation, and was seen in nerve fibres in skin and corneal epithelium. In summary, our results suggest that P2X3 is expressed by a functionally heterogeneous population of BSI-B4-binding sensory neurons, and is transported into both central and peripheral processes of these neurons.     

Pigmentation phenotypes of variant extension locus alleles result from point mutations that alter MSH receptor function

Coat colors in the chestnut horse, the yellow Labrador retriever, the red fox, and one type of yellow mouse are due to recessive alleles at the extension locus. Similarly, dominant alleles at this locus are often responsible for dark coat colors in mammals, such as the melanic form of the leopard, Panthera pardus. We show here that the murine extension locus encodes the melanocyte-stimulating hormone (MSH) receptor. In mice, the recessive yellow allele (e) results from a frameshift that produces a prematurely terminated, nonfunctioning receptor. The sombre (Eso and Eso-3J) and tobacco darkening (Etob) alleles, which both have dominant melanizing effects, results from point mutations that produce hyperactive MSH receptors. The Eso-3J receptor is constitutively activated, while the Etob receptor remains hormone responsive and produces a greater activation of its effector, adenylyl cyclase, than does the wild-type allele.     

The aminothiol WR-1065 protects T lymphocytes from ionizing radiation-induced deletions of the HPRT gene

Aminothiols, such as WR-2721 and its active free thiol, WR-1065, reduce mutations from ionizing radiation in exponentially growing cells. In this study, human noncycling G0 T lymphocytes were exposed in vitro to gamma-irradiation in the presence or absence of WR-1065. The five treatment groups were: (a) control; (b) treatment with 4 mM WR-1065; (c) treatment with 3 Gy of gamma-radiation, from a 137Cs source; and (d) and (e) treatment with WR-1065 30 min prior to or 3 h after 3 Gy of gamma-irradiaiton, respectively. A total of 224 cloned HPRT mutants representing 179 independent mutations were analyzed for genetic alterations using multiplex PCR. Ionizing radiation alone significantly increased the percentage of mutations with gross structural alterations compared to controls (P = 0.02). Although the frequency of such large structural mutations was not different from control cells treated with WR-1065 alone, this aminothiol significantly reduced their frequency among irradiated mutants (P = 0.01) when the radioprotector was present during the irradiation. Addition of WR-1065 3 h postirradiation also greatly reduced the percentage of gross structural alterations; however, due to small numbers, this was not statistically significant. This is the first demonstration that the antimutagenicity of WR-1065 in human cells specifically protects against these kinds of large-scale DNA alterations induced by ionizing radiation. WR-1065 and similar aminothiol compounds may afford protection against radiation-induced mutations through polyamine-like processes, e.g., stabilization of chromatin structure, inhibition of cell proliferation, and influences on DNA repair systems.     

Collection of peripheral blood progenitor cells after the administration of cyclophosphamide, etoposide, and granulocyte-colony-stimulating factor: an analysis of 497 patients

BACKGROUND: There is great interpatient variability in the number of peripheral blood stem cells collected, as measured by CD34+ cell content, after the administration of chemotherapy and a growth factor. The ability to predict patients who fail to yield adequate quantities of CD34+ cells would be of value. However, very few reports include large numbers of patients treated in an identical fashion. STUDY DESIGN AND METHODS: Between 1991 and 1995, 497 consecutive patients with a variety of malignant diseases received cyclophosphamide (4 g/m2), etoposide (600 mg/m2), and granulocyte-colony-stimulating factor (6 micrograms/kg/day) for mobilization and collection of a target dose > or = 2.5 x 10(8) CD34+ cells per kg. Multivariate analyses were performed to determine the factors associated with failure to achieve this target harvest. RESULTS: A median of 14.71 x 10(6) CD34+ cells per kg (range, 0.08-137.55) was harvested with a median of 2 (range, 1-11) apheresis procedures. Ninety-one percent of patients yielded > or = 2.5 x 10(5) CD34+ cells per kg. Patients with Stage II-III breast cancer, who had pretreatment platelet counts > or = 150 x 10(9) per L and patients who underwent < or = 1 prior chemotherapy regimen had improved CD34+ cell yields. However, most patients with adverse risk factors yielded > or = 2.5 x 10(6) CD34+ cells per kg. CONCLUSION: A regimen of cyclophosphamide, etoposide, and granulocyte-colony-stimulating factor led to the successful collection of adequate numbers of CD34+ cells in most patients without excessive toxicity. These observations confirm previous reports that intense prior therapy adversely affects the quantity of CD34+ cells harvested. Pretreatment and posttreatment variables did not predict with any certainty the small fraction of patients who fail to yield > or = 2.5 x 10(6) CD34+ cells per kg via multiple apheresis procedures.     

Effects of climatic and management factors on conception rate of dairy cattle in subtropical environment

Breeding records, representing 12,038 inseminations at Bassett's Dairy Farm (Monticello, FL), were analyzed to document effects of environmental and management factors on fertility of dairy cattle from January 1, 1975 to December 31, 1977. Conception rates of lactating cows decreased sharply when maximum air temperature on day after insemination exceeded 30 degrees C. In contrast, conception rates for heifers did not decline until 35 degrees C. Virgin heifers had higher conception rates for all services (50%) than lactating cows (34%) and suffered only slight depression of fertility during summer months. Heifers required 1.5 services per conception compared with 2.3 for lactating cows. Relationship between conception rate and rainfall on day after insemination was negative and curvilinear. Jerseys had higher conception rates (45%) than Holstein (39%) and Brown Swiss (41%). Services per conception were 1.7, 2.0, and 1.9. Substantial decreases of fertility were associated with advancing service number. Estrous status (standing; positive heat detection patch; mounting activity), inseminator, and year of service were related to variation of conception rate. Seasonal effects on fertility of lactating cows were marked. Thus, environmental management of the postpartum cow during hot summer months is warranted to maximize fertility.     

Neurotoxicity following the ingestion of a Chinese medicinal plant, Alocasia macrorrhiza

1. A case of poisoning due to the raw root tuber of a Chinese medicinal plant, Alocasia macrorrhiza is presented. 2. The patient developed neurological (severe pain and numbness in the perioral area and throat) and gastrointestinal (nausea, vomiting, abdominal pain) symptoms immediately after eating the root tuber. 3. A macrorrhiza has properties and morphology very similar to another medical plant. A. odora. The root tuber of the latter is known to contain a neurotoxin sapotoxin.