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1.
We investigated the properties of neurons located in the distal forelimb field of dorsal premotor area F2 of macaque monkey using a behavioral paradigm for studying the neuronal discharge during observation (object fixation condition) and grasping of different 3-dimensional objects with and without visual guidance of the movement (movement in light and movement in dark conditions, respectively). The main result is that almost all studied neurons were selective for both the type of prehension and the wrist orientation required for grasping an object. Three categories of neurons were found: purely motor, visually modulated, and visuomotor neurons. The discharge of purely motor neurons was not affected by either object presentation or by the visual feedback of the hand approaching to and interacting with the object. Visually modulated neurons presented a different discharge in the 2 movement conditions, this determining a decrease in selectivity for the grip and wrist orientation in the movement in dark condition. Visuomotor neurons typically discharged during the object fixation task even in the absence of any grasping movement. Nine of them also displayed a different discharge rate between the 2 movement conditions. Congruence was observed between the neuron response during the most effective type of prehension and the neuron response during observation of the object requiring that particular prehension. These results indicate an important role of F2 in the control of goal-related hand movements.  相似文献   
2.
We have tested folinic acid (FA) for ability to increase peripheral blood stem cells (PBSC) after chemotherapeutic aplasia in acute leukaemia. Five adult patients (four AML, one ALL) entered the study, each patient underwent two series of three leukapheresis, the first following induction chemotherapy and the second following the first course of consolidation. The first leukapheresis of each series was done when the white blood cell count reached 109/1 with subsequent leukapheresis every other day. Folinic acid (Lederle Laboratories, France) was administered at a dose of 50 mg (i.v.) per day, 15 days from initiation of chemotherapy and continuing through the third leukapheresis of the series (days 25–30). PBSC were collected on a Haemonetics V50 cell separator.
In these five cases we observed an increased yield of both colony-forming units, granulocyte macrophage (CFU-GM) and burst forming units-erythroid (BFU-E) expressed per ml of cytapheresis product: CFU-GM × 18, BFU-E × 3 and if expressed per 104/kg of body weight: CFU-GM × 30, BFU-E×3 (CFU-GM P <0·05, BFU-E<0·01). Long-term blood culture (LTSC) from FA stimulated leukapheresis, in an attempt to quantitate the most primitive stem cells, demonstrated that this expansion of the PBSC was sustained in time. We found by means of LTSC that FA did not stimulate CFU-L from patients with AML (two cases tested).
Finally two AML patients were grafted with FA-PBSC after Cytotoxan and total body irradiation (TBI). Haematopoietic reconstitution was rapid complete and sustained in time in both patients.
This indication for folinic acid should be further studied with or as an alternative to haematopoietic growth factors.  相似文献   
3.
We have previously established a serum-free (SF) culture medium, which supports normal haemopoietic progenitor cell growth for at least 4 weeks as does conventional serum dependent (SD) medium. In the present study, we investigated the efficacy of such a defined SF liquid medium which sustained in vitro residual normal haemopoietic proliferation of marrow derived from ALL patients and which was detrimental for the leukaemic population. Evidence for a potential selective effect of SF culture was obtained by a leukaemic progenitor cell assay (ALL-CFU) and the detection of the bcr/abl translocation by polymerase chain reaction (PCR). In 13 experiments including 12 patients, morphological blast cells and ALL-CFU were dramatically reduced within 3 weeks of incubation in both SF and SD cultures. Likewise, in 5/5 experiments in SD and 2/5 experiments in SF conditions, leukaemic cells expressing the bcr/abl fusion gene disappeared within 3-4 weeks. In contrast, the absolute numbers of supernatant cells harvested weekly from SF and SD cultures were similar. No difference in CFU-GM production was detected for the two culture systems. Erythropoiesis in SF medium exhibited a slower decline than that found in SD. These results indicate that liquid marrow culture may selectively deplete leukaemic lymphoblastic cells and enable repopulation by residual normal haemopoietic cells. This technique may be useful to purge leukaemic cells for clinical autologous bone marrow transplantation in patients with ALL.  相似文献   
4.
The use of a semisolid support like methylcellulose (MC) in a clonogenic assay prevents cell migration and nonspecific aggregation. However, the inhibitory effect of MC on myeloid cell lines has been reported. To assess the effect of MC on human leukemic progenitor cell growth (acute myeloblastic leukemia colony-forming units, AML-CFU), increasing concentrations of MC (0.36%, 0.72%, and 1.44%) were added in a double-feeder culture system. T-lymphocyte-depleted leukemic cells from 12 patients with AML were cultured in the presence of 2.5% phytohemagglutinin (PHA) in a liquid and a semisolid (MC) medium over a leukocyte feeder layer. The leukemic nature of the colonies was confirmed by cytogenetic studies. The median cloning efficiency in the optimal MC assay system was significantly higher (217 leukemic colony-forming units [CFU-L]/5 x 10(4) cells) than the one obtained in the liquid assay system (72.5 CFU-L/5 x 10(4) cells). However, three patterns of growth were observed: 1) colony formation was significantly better in MC than in the liquid assay system (seven of ten cases), 2) there was no difference in growth response (three of ten cases), and 3) colony formation was significantly better in the liquid assay system (one of ten cases). In the semisolid assay system, colony growth was dependent on MC concentration and varied among individual patients. A striking feature was the partial reduction of AML-CFU growth at 1.44% MC, with complete inhibition in 4/11 cases. This phenomenon was not observed for normal progenitors cultured under the same conditions. Cytological evaluation of AML-CFU showed an incomplete maturation to the myelocyte state, accompanied occasionally by macrophagic differentiation. In contrast, maturation of the granulocyte-macrophage colony-forming unit (CFU-GM) clones was harmonious, resulting in greater than 40% polynuclear cells, even from a 7-day culture. Despite a variable clonal response of leukemic progenitors from individual patients, we conclude that 0.72% MC is the optimal concentration of MC in our system, allowing clonal growth of AML-CFU.  相似文献   
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OBJECTIVE: To determine the diagnostic accuracy of C-reactive protein (CRP) for alcoholic hepatitis in heavy drinkers. MATERIAL AND METHODS: A total of 101 heavy drinkers (67 M, 34 F) with elevated transaminase activity and negative HBsAg, anti-HCV and anti-HIV antibodies were included in the study. All patients underwent standard liver function tests, CRP determination and liver biopsies. None of the patients had signs of infection or inflammatory disease and none of them were taking antibiotics. The severity of alcoholic hepatitis was assessed semi-quantitatively using a Metavir-derived scoring system. The receiver operating curve (ROC) for CRP was constructed to assess different areas under the curve (AUCs) and the best threshold value for predicting alcoholic hepatitis (an AUC of 1.0 for an ideal test and of 0.5 for a less indicative test). RESULTS: Pathological signs of alcoholic hepatitis were found in 29 patients (30%) and significant fibrosis (F > 1) in 46 (45.1%). CRP increased significantly with the severity of acute alcoholic hepatitis (p<0.001). Total bilirubin (OR = 1.03 CI 95% (1.01-1.06), p=0.04) and CRP (OR = 1.1 CI 95% (1.02-1.19), p=0.01) were independent factors for predicting alcoholic hepatitis. The area under the ROC curve of CRP was 0.78. Using optimized cut-off values (CRP > 19 mg/L), the sensitivity, specificity, positive, negative predictive value and diagnostic accuracy were 41%, 99%, 92%, 81% and 82%, respectively. CONCLUSION: CRP is an accurate marker of alcoholic hepatitis.  相似文献   
7.
We investigated the motor and visual properties of F5 grasping neurons, using a controlled paradigm that allows the study of the neuronal discharge during both observation and grasping of many different three-dimensional objects with and without visual guidance. All neurons displayed a preference for grasping of an object or a set of objects. The same preference was maintained when grasping was performed in the dark without visual feedback. In addition to the motor-related discharge, about half of the neurons also responded to the presentation of an object or a set of objects, even when a grasping movement was not required. Often the object evoking the strongest activity during grasping also evoked optimal activity during its visual presentation. Hierarchical cluster analysis indicated that the selectivity of both the motor and the visual discharge of the F5 neurons is determined not by the object shape but by the grip posture used to grasp the object. Because the same paradigm has been used to study the properties of hand-grasping neurons in the dorsal premotor area F2, and in the anterior intraparietal area (AIP), a comparison of the functional properties of grasping-related neurons in the three cortical areas (F5, F2, AIP) is addressed for the first time.  相似文献   
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9.
The aim of the present systematic review is to summarize the existing knowledge about the human microbiota in the elderly and the effects of probiotics in elderly population. The elderly subjects, compared to adult population, show a reduction in the diversity of the microbiota, characterized by a large interindividual variability, with lower numbers of Firmicutes, Bifidobacteria, Clostridium cluster XIV, Faecalibacterium Prausnitzii, Blautia coccoides-Eubacterium rectal and higher presence of Enterobacteriaceae and Bacteroidetes. These differences of the intestinal microbiota of the elderly may not necessarily be caused by aging, but they could be associated with the decline of the general state of health with malnutrition and with increased need for medication, such as antibiotics and nonsteroidal anti-inflammatory drugs, situations that occur frequently in the elderly. Differences have been demonstrated in the composition of the microbiota between healthy elderly subjects and hospitalized or institutionalized elderly subjects. These findings which further indicates that the living conditions, health status, nutrition and drugs have a significant effect on the composition of the microbiota. According to the available knowledge, the use of probiotics is safe and could represent an useful intervention to prevent or treat antibiotic-associated diarrhea, in addition to reducing the severity of symptoms, other than to help the management of constipation.  相似文献   
10.

Introduction

Polycystic ovary syndrome (PCOS) is associated with numerous metabolic morbidities (insulin resistance (IR), central obesity) and various nutritional abnormalities (vitamin D deficit, mineral milieu alterations, omega6/omega3 PUFA ratio unbalance).

Methods

We performed a systematic literature review to evaluate the till-now evidence regarding: (1) the metabolic and nutritional correlates of PCOS; (2) the optimum diet therapy for the treatment of these abnormalities. This review included 127 eligible studies.

Results

In addition to the well-recognized link between PCOS and IR, the recent literature underlines that in PCOS there is an unbalance in adipokines (adiponectin, leptin, visfatin) production and in omega6/omega3 PUFA ratio. Given the detrimental effect of overweight on these metabolic abnormalities, a change in the lifestyle must be the cornerstone in the treatment of PCOS patients. The optimum diet therapy for the PCOS treatment must aim at achieving specific metabolic goals, such as IR improvement, adipokines secretion and reproductive function. These goals must be reached through: accession of the patient to hypocaloric dietary program aimed at achieving and/or maintaining body weight; limiting the consumption of sugar and refined carbohydrates, preferring those with lower glycemic index; dividing the food intake in small and frequent meals, with high caloric intake at breakfast; increasing their intake of fish (4 times/week) or taking omega3 PUFA supplements; taking Vitamin D and chromium supplementation, if there are low serum levels.

Conclusion

Lifestyle intervention remains the optimal treatment strategy for PCOS women. A relatively small weight loss (5 %) can improve IR, hyperandrogenism, menstrual function, fertility.  相似文献   
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