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991.
Baroncelli GI Federico G Vignolo M Valerio G del Puente A Maghnie M Baserga M Farello G Saggese G;Phalangeal Quantitative Ultrasound Group 《BONE》2006,39(1):159-173
Bone mineral status by phalangeal quantitative ultrasound (QUS, DBM Sonic, IGEA, Carpi, Modena, Italy) was examined in 3044 (1513 males and 1531 females) healthy subjects, aged 2-21 years. The aim of the study was to provide a reference database for phalangeal QUS parameters, amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT), both expressed as centiles and Z score, according to gender, age, height, weight, body mass index (BMI), and pubertal stage to be used for estimating bone mineral status in patients with disorders of growth or of bone and mineral metabolism. In both sexes, AD-SoS and BTT increased significantly (P<0.0001) according to all the anthropometric variables. Females showed higher values than males in the age groups 9-14 for AD-SoS (P<0.04-P<0.0001) and in the age groups 11-13 for BTT (P<0.02). Males had higher BTT values than females in the age groups 6-8 and 15-21 (P<0.04-P<0.0001). AD-SoS was higher (P<0.02-P<0.0001) in females than in males at pubertal stages 2, 3, and 4, but it was higher (P=0.001) in males compared with females at pubertal stage 5. BTT was higher in males than females at pubertal stages 1 (P<0.0001), 2 (P<0.01), and 5 (P<0.0001). In both sexes, AD-SoS and BTT were significantly correlated between them (r=0.92, P<0.0001) and with all the anthropometric variables (r=0.53-r=0.85, P<0.0001). Age, weight, BMI, and pubertal stage were independent predictors of AD-SoS in males; age and pubertal stage were independent predictors of AD-SoS in females. In both sexes, height and pubertal stage, and also age only in females, were independent predictors of BTT. In conclusion, our data show that gender, age, height, and timing of sexual maturation are main determinants of bone structure and geometry, and that both these two processes may be captured by phalangeal QUS. It may be a useful tool to assess bone mineral status from early childhood to young-adulthood with a very small confounding effect related to bone sizes and without exposing the subjects to a source of radiation. 相似文献
992.
Caramello P Canta F Bonino L Moiraghi C Navone F Lipani F Balbiano R Caputo AM Gai V 《Journal of travel medicine》2002,9(6):326-329
Hantaviruses belong to the Bunyaviridae family, which is comprised of Bunyavirus, Phlebovirus, Nairovirus, and Hantavirus. Euroasiatic Hantaviruses belong to two distinct subfamilies: Murinae (comprising Hantaan, Dobrava, and Seoul viruses), which are responsible for hemorrhagic fever with renal syndrome (HFRS), and Arvicolinae (comprising Puumala virus), responsible for nephropathia epidemica (NE) and HFRS. On the contrary, the New World Hantavirus belongs to the Sigmodontinae subfamily and includes the North American viruses: Sin Nombre, Monongahela; New York, Bayou, Black Creek Canal, and the South American, which comprise the Andes, Oran, Lechiguanas, Laguna Negra, Juquitiba; both groups are responsible for the hantavirus pulmonary syndrome (HPS). 相似文献
993.
Valerio G Franzese A Palmieri A Mackay DJ Gardner RJ Temple IK 《Journal of pediatric endocrinology & metabolism : JPEM》2001,14(7):897-900
We describe a girl with triple X syndrome and paternal isodisomy of chromosome 6 (UPD6), who developed neonatal diabetes mellitus (NDM) and precocious puberty. At birth she presented growth retardation and congenital anomalies (ventricular septal defect, macroglossia, umbilical hernia). Diabetes mellitus (DM) was diagnosed at 31 days of life and treated with insulin for 13 months. DM recurred at 4 years of age and since that time it required insulin, in spite of preserved beta-cell function. Tall stature was present from early childhood. At 7 years of age the girl presented central precocious puberty, height velocity further increased, but her near-final height was normal. This patient is unique in that precocious puberty has never been described in triple X females. Moreover it is a further example of paternal UPD6 causing NDM with a predisposition to type 2 DM in later life. 相似文献
994.
Simultaneous analysis of surface marker expression and cell cycle progression in human peripheral blood mononuclear cells 总被引:1,自引:0,他引:1
Rosato MT Jabbour AJ Ponce RA Kavanagh TJ Takaro TK Hill JP Poot M Rabinovitch PS Faustman EM 《Journal of immunological methods》2001,256(1-2):35-46
One method for examining cell cycle kinetics by flow cytometry uses continuous DNA labeling with bromodeoxyuridine (BrdU), a thymidine analogue. Upon incorporation into DNA, BrdU causes stoichiometric quenching of the DNA fluorochrome Hoechst 33258. After counterstaining with a secondary DNA fluorochrome (e.g., ethidium bromide), the analyst can distinguish cells in different phases of the cell cycle over a number of mitotic cycles with flow cytometry. In this report, we describe a modification of the flow cytometric BrdU-Hoechst assay that allows combined analysis of cell proliferation and immunophenotyping at the single cell level. To demonstrate an application of this method, human peripheral blood mononuclear cells were stimulated with tetanus toxoid or interleukin-2 for up to 6 days in the presence of BrdU, harvested, and immunostained for the cell surface markers CD3, CD4, CD8, CD14, CD19, and the cytokine receptor, CCR5. We used four-color flow cytometry analyses to simultaneously measure cell proliferation and surface marker expression, for the purpose of immunophenotyping and identifying specific cell subsets responding to antigen stimulation. Our successful application of this method suggests that it may be used to study immune responses at the molecular and cellular level and to identify mechanisms of immune system modulation. 相似文献
995.
996.
Chang JH Vines E Bertsch H Fraker DL Czerniecki BJ Rosato EF Lawton T Conant EF Orel SG Schuchter L Fox KR Zieber N Glick JH Solin LJ 《Cancer》2001,91(7):1231-1237
BACKGROUND: Advances in the diagnosis and treatment of breast carcinoma have led to a multidisciplinary approach to management for patients with breast carcinoma. To assess the effect of this approach, the authors performed an evaluation for a cohort of patients examined in a multidisciplinary breast cancer center. METHODS: An analysis was performed for the records of 75 consecutive women with 77 breast lesions examined in consultation in a multidisciplinary breast cancer center between January and June 1998. Each patient's case was evaluated by a panel consisting of a medical oncologist, surgical oncologist, radiation oncologist, pathologist, diagnostic radiologist, and, when indicated, plastic surgeon. A comprehensive history and physical examination was performed, and the relevant mammograms, pathology slides, and medical records were reviewed. Treatment recommendations made before this evaluation were compared with the consensus recommendations made by the panel. RESULTS: For the 75 patients, the multidisciplinary panel disagreed with the treatment recommendations from the outside physicians in 32 cases (43%), and agreed in 41 cases (55%). Two patients (3%) had no treatment recommendation before consultation. For the 32 patients with a disagreement, the treatment recommendations were breast-conservation treatment instead of mastectomy (n = 13; 41%) or reexcision (n = 2; 6%); further workup instead of immediate definitive treatment (n = 10; 31%); treatment based on major change in diagnosis on pathology review (n = 3; 9%); addition of postmastectomy radiation treatment (n = 3; 9%); or addition of hormonal therapy (n = 1; 3%). CONCLUSIONS: The multidisciplinary breast cancer evaluation program provided an integrated program in which individual patients were evaluated by a team of physicians and led to a change in treatment recommendation for 43% (32 of 75) of the patients examined. This multidisciplinary program provided important second opinions for many patients with breast carcinoma. 相似文献
997.
Gender-associated mitochondrial DNA heteroplasmy in the venerid clam Tapes philippinarum (Mollusca Bivalvia) 总被引:5,自引:0,他引:5
This paper provides evidence of a gender-associated mitochondrial DNA (mtDNA) heteroplasmy in the clam Tapes philippinarum. The pattern of tissue distribution of the two observed mtDNA types (referred to as M and F) parallels that of the doubly
uniparental inheritance system of Mytilus. The mitochondrial genetic features of the clam are related to a different rate of evolution of the M- and F-type mtDNAs.
Since clams are known to be phylogenetically very distant from mussels, the present findings support the hypothesis that the
mechanism producing gender-associated heteroplasmy should be considered an ancestral character in the Bivalvia.
Received: 2 August 2000 / Accepted: 3 December 2000 相似文献
998.
999.
Valerio Magnaghi Ilaria Cavarretta Mariarita Galbiati Luciano Martini Roberto C. Melcangi 《Brain Research Reviews》2001,37(1-3)
The present review summarizes observations obtained in our laboratories which underline the importance of neuroactive steroids (i.e., progesterone (PROG), dihydroprogesterone (5α-DH PROG), tetrahydroprogesterone (3α, 5α-TH PROG), testosterone (T), dihydrotestosterone (DHT) and 5α-androstan-3α,17β-diol (3α-diol)) in the control of the gene expression of myelin proteins (i.e. glycoprotein Po (Po) and the peripheral myelin protein 22 (PMP22)) in the peripheral nervous system. Utilizing different in vivo (aged and adult male rats) and in vitro (Schwann cell cultures) experimental models, we have observed that neuroactive steroids are able to stimulate the mRNA levels of Po and PMP22. The effects of these neuroactive steroids, which are able to interact with classical (progesterone receptor, PR, and androgen receptor, AR) and non-classical (GABAA receptor) steroid receptors is further supported by our demonstration in sciatic nerve and/or Schwann cells of the presence of these receptors. On the basis of the observations obtained in the Schwann cells cultures, we suggest that the stimulatory effect of neuroactive steroids on Po is acting through PR, while that on PMP22 needs the GABAA receptor. The present findings might be of importance for the utilization of specific receptor ligands as new therapeutical approaches for the rebuilding of the peripheral myelin, particularly in those situations in which the synthesis of Po and PMP22 is altered (i.e. demyelinating diseases like Charcot–Marie–Tooth type 1A and type 1B, hereditary neuropathy with liability to pressure palsies and the Déjérine–Sottas syndrome, aging, and after peripheral injury). 相似文献
1000.
Valerio Torre Sebastiano Bucolo Giuseppe Abbate Francesca Albiero Rocco Cicciarello Vittorio Cavallari 《Pathology, research and practice》2001,197(6):449-452
Primary adenocarcinoma of the larynx is a rare neoplasm that tends to spread to both regional lymph nodes and distant sites. A case of primary adenocarcinoma of the arytenoid in a 74-year-old man is presented. The tumor was evaluated by light and electron microscopy. A high percentage of intranuclear pseudoinclusions (more than 20% of the neoplastic cells) was a peculiar characteristic of the tumor. To the best of our knowledge, such a feature has not been reported previously and should be considered a hallmark of more aggressive behavior. 相似文献