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2.
Mesenchymal stem cells (MSC), easily culture-expanded from bone marrow, can significantly enhance bone defect healing. Several proteins, such as the bone morphogenetic proteins (BMPs) and in particular BMP-7, are involved in bone formation in vitro and in vivo. In this preclinical study, we evaluated if the association of human MSC (hMSC) with BMP-7 had synergic action on bone healing. Rat femoral defects (n=12) were treated with: autoclaved bone and mononucleated cells (MNC) as control group G1; bone and hMSC, group G2; bone with BMP-7, group G3; bone and hMSC plus BMP-7, group G4. Defect regeneration was evaluated with plain radiographs after 2, 4, 8 and 12 weeks and with histological analysis. We observed organized trabeculae bridging between the osteotomic ends of the host bone in rats treated with the association of hMSC and rhBMP-7. These trabeculae, formed by a core of devitalized tissue surrounded by osteoblasts, osteocytes and osteoclasts, were continuous with a cortical-like structure of bony tissue. Such new bone formation of the group treated with the association of hMSC and rhBMP-7 (G4) was clearly superior compared to rats treated with rhBMP-7 (G2) or hMSC (G3) alone, as shown by radiographic analysis and histological study. The present study suggests that the association of hMSC and BMP-7 is more effective than hMSC or BMP-7 alone in the healing of femoral defects in rats. Further studies with larger samples are required to confirm these results and to evaluate the best dosage.  相似文献   
3.
Treatment with gonadotropin-releasing hormone (GnRH) agonist leads to enhanced bone turnover and accelerated bone loss in premenopausal women with endometriosis, uterine leiomyomatomas and hirsutism. Sodium etidronate is a powerful inhibitor of bone resorption which has been proven efficacious in the prevention and treatment of postmenopausal osteoporosis. The objective of this study was to evaluate the skeletal effects of 6 months of therapy with the depot preparation of the GnRH agonist triptorelin (decapeptil 3.75 mg intramuscularly every 4 weeks) in 24 hirsute patients, aged 24–33 years, with hyperandrogenic chronic anovulation. Ten patients also received cyclical etidronate in an oral dose of 400 mg/day for 2 weeks, followed by an 11-week period of 500 mg/day elemental oral calcium (one cycle). The remaining 14 patients received 500 mg/day of elemental calcium continuously. After 6 months all treatments were discontinued for at least a further 6 months. Bone mineral density (BMD) at lumbar spine and hip (dual-energy X-ray absorptiometry, Sophos LXRA, France) and biochemical markers (serum alkaline phosphatase, osteocalcin, urinary N-telopeptide and hydroxyproline/creatinine ratio) were evaluated at baseline, 6 months and 12 months. In the group given GnRH agonist alone BMD fell significantly at all measured skeletal sites during the first 6 months. In the patients treated with etidronate a significant decrease in BMD was observed at lumbar spine but not in the femoral neck and trochanter, and the changes at lumbar spine and trochanter were significantly smaller than those in the control group. At 6 months bone turnover was also increased in patients treated with GnRH and calcium. Cyclical etidronate prevented the increase in biochemical markers of bone formation and resorption, with the exception of calcium/creatinine excretion, which was significantly increased in both groups. Six months after treatment withdrawal BMD did not recover in either group. Biochemical markers (N-telopeptide, serum alkaline phosphatase) remained increased in those patients previously treated with calcium alone while they remained close to baseline values in the patients treated with cyclical etidronate.Our study indicates that: (1) GnRH agonist therapy causes remarkable bone loss in young individuals with androgen excess who are expected to have increased bone mass; (2) this bone loss can be partially prevented by intermittent cyclical etidronate therapy.  相似文献   
4.
Eight nonsmoking subjects with asthma, nonresponsive to the bronchoconstrictive effect of oral propranolol, were studied. The airway response to increasing concentrations of histamine aerosol was assessed by measuring FEV1. The threshold provocative dose of histamine needed to cause a 20% fall in starting FEV1 (PD20) was measured by log dose-response curve. Histamine challenge was performed in duplicate after premedication with placebo or 40 mg of propranolol on separate days. The mean starting FEV1 did not change significantly after placebo and after propranolol administration. The mean PD20 values after propranolol (0.37 mg/ml and 0.32 mg/ml, respectively, for the first and the second challenge) were significantly lower (p less than 0.01) than mean control PD20 values (1.36 mg/ml and 1.48 mg/ml, respectively, for the first and the second challenge). These results indicate that propranolol increases airway responsiveness to histamine, even in those subjects with asthma in whom propranolol has little bronchoconstrictive effect.  相似文献   
5.
Peripheral blood mononuclear cell populations in ten men, with idiopathic infertility with serum sperm agglutinating antibodies at a titre of 1/32, were evaluated. Mononuclear cells were enumerated using the monoclonal antibodies OKT3 (pan T cells), OKT4 (helper/inducer T cells), OKT8 (suppressor/cytotoxic T cells), Leu 7 (monocytes, null cells, and natural killer (NK) cells), OKIa (B cells, monocytes, null cells and activated T cells). Blood mononuclear cells with surface receptors for complement (B lymphocytes and a proportion of monocytes and null cells) were enumerated using a rosette test (EAC). The following abnormalities, compared to normal subjects, of blood mononuclear cell population were found: a decreased percentage of OKT3 (+) cells (p less than 0.01), a decreased percentage of OKT8 + cells (p less than 0.001) and increased OKT4/OKT8 ratio (p less than 0.001), an increased percentage of OKIAI cells (p less than 0.001). Levels of OKT4+ and Leu 7 cells and the percentage of EAC rosette forming cells were not significantly different from those in normal subjects. Regression analysis showed a significant correlation between the percentage of OKIAI cells and sperm agglutinating antibodies. After all that, significant correlation between humoral and cell-mediated immunity in patients with idiopathic infertility with antisperm autoantibodies, were observed.  相似文献   
6.
Background:A worldwide personal protection equipment (PPE) shortage has emerged during COVID-19 pandemic, contributing to the high incidence of SARS-CoV-2 infection among health care providers. To address this lack of PEE, new solutions have been researched. Among those, full-face snorkeling masks demonstrated to be an interesting option. Among surgical specialties otolaryngologists and thoracic surgeons are at high risk of infection, due to the close contact with airway secretions.Objectives:We tested the comfort and usability of a modified full-face snorkeling mask (Ocean Reef Mask Aria QR+) as a protective device for otolaryngologic and thoracic surgeries.Methods:The mask was customized with a 3D-printed adaptor supporting many industrial filter types, including FFP3 and heat and moisture exchangers (HME). We evaluated surgical performances of the mask, both subjectively, with a questionnaire filled in by the surgeons, as well as objectively, monitoring transcutaneous PCO2 and PO2 values of surgeons during surgical procedures.Results:The modified full-face snorkeling mask was tested during 9 otolaryngologic and 15 thoracic surgery procedures. The device demonstrated very good overall vision quality with some limitations regarding lateral vision and almost no difficulties in usability. Water condensation into the mask was absent in almost every case. Both PO2 and PCO2 parameters remained within normal ranges during every procedure.Discussion:The modified full-face snorkeling mask can be an innovative PPE. In the current COVID-19 pandemic scenario, the worldwide shortage of protective masks and goggles may exploit this ready-to-use and low-cost solution, especially for high-risk surgical procedures.  相似文献   
7.
Abstract

Information on children’s diet including bioactive compounds is quite scarce. This observational study investigated the composition of the diet of children living in Parma (Italy; n?=?172, 8–10?years) using 3-day food records completed in winter and spring. Mean daily intakes of food groups, energy and nutrients were obtained using the national food database, while (poly)phenol contents were estimated from Phenol-Explorer or by specific literature searches. Food consumption, energy and nutrient intakes decreased in spring and were partially in line with national data. Adherence to the nutritional recommendations was not satisfied for the majority of nutrients. Main contributors to the phenolic intake were flavonoids (flavan-3-ols) and phenolic acids (hydroxycinnamic acids), while main dietary sources were fruit, chocolate-based products, vegetables, and tea & coffee (decaffeinated). This study provided the first comprehensive analysis of the nutritional composition of children’s diet. Future research should look at the health implications of dietary choices in children.  相似文献   
8.
In neuroblastoma, high levels of mRNA for p14h trkA and p75 LNGFR neurotrophin receptors are predictive of favorable outcome. Their evaluation by Northern blot, however, requires substantial amounts of tissue and this prevents their routine evaluation as well as the possibility for multicenter studies to be easily carried out. In an attempt to overcome these limitations, the feasibility and reliability of determining both neurotrophin receptors on cryostat sections by immunohistochemistry were assessed, and these findings were compared to those obtained from Northern blot analysis. Primary tumor samples from 28 untreated patients at all stages were evaluated by using H10 anti-p140 trkA and ME20.4 anti-p75 LNGFR mAbs. Although weak, positiveimmunostaining was found in 9 of 28 tumors for p140 trkA and in 5 of 28 tumors for p75 LNGFR . As compared to Northern blot, the concordance rate was 79% (22 of 28 cases) for p140 trkA (p < 0.05) and 71% (20 of 28 cases) for p75 LNGFR (p < 0.05). No case negative for Northern blot was found to be positive with immunohistochemistry. Since only high mRNA levels for both receptors have been shown to be clinically relevant, their immunohistochemical detection, although less sensitive than Northern blot, can be just as sufficient and reliable as a prognostic tool, and possibly with a better cost-benefit ratio.  相似文献   
9.
A clinical case concerning differential diagnosis between tetanus, atropine poisoning and acute hypocalcemia is reported. A 51 year-old man has been hospitalized in ICU, coming from the emergency service of another hospital, with a diagnosis of suspected atropine poisoning (he had been under treatment with atropine collyrium 1% for same days). The patient at the moment of hospitalization presented: preserved coscience with good orientation in time and space, thrismus, slight nuchal rigidity, hypertonia to the inferior limbs, accentuated osteotendinous reflex to the four limbs, asthenia, intense perspiration, tachycardia, apyrexia and not appreciable ocular signs for previus pathology. At observation the patient showed to have had a thyroidectomy (presence of surgical scar), and he didn't remember to have been vaccinated against tetanus. Several small scars to the hands were observed (particularly a recent felon to the first finger of the rigth hand) all referable to his activity as agriculture laborer. The hematochemical examinations were performed and the slight hypocalcemia slightly laver than normal, the leukocytosis neutrophilia, apyrexia, abundant perspiration and preserved conscience in presence of thrismus and hypertonia to the inferior limbs led to the diagnosis of a possible case of tetanus.  相似文献   
10.
PURPOSE: Recently, we reported that a large number of human hepatocellular cancer (HCC) cell lines were auxotrophic for arginine. Here we report the results obtained with the amino acid-degrading enzyme arginine deiminase (ADI) conjugated to polyethylene glycol (ADI-SS PEG 20,000 mw) as a means of lowering plasma arginine to treat HCC. The study was a cohort dose-escalation phase I/II study. PATIENTS AND METHODS: Pharmacodynamic studies indicated an ADI-SS PEG 20,000 mw dose level of 160 U/m(2) was sufficient to lower plasma arginine from a resting level of approximately 130 micromol/L to below the level of detection (< 2 micromol/L) for more than 7 days, a dose later defined as the optimal biologic dose. All patients were to receive three cycles at the optimum biologic dose. RESULTS: This therapy was well tolerated, even in patients who had no detectable plasma arginine for 3 continuous months of therapy. Of the 19 patients enrolled, two had a complete response, seven had a partial response, seven had stable disease, and three had progressive disease. The median survival for the 19 patients enrolled on this study was 410 days, with four patients still alive at present (> 680 days). CONCLUSION: Elimination of all detectable plasma arginine in patients with HCC was well tolerated and seemed to be effective in the treatment of some patients with HCC. Further testing of ADI-SS PEG 20,000 mw in a larger population of individuals with HCC as well as other human tumors auxotrophic for arginine is warranted.  相似文献   
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