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91.
We report on a case of Prader-Willi syndrome (PWS) with a true reciprocal unbalanced translocation, 45,XX,-15,der(11)t(11;15)pat. The proposita was diagnosed clinically as having severe PWS. Molecular studies revealed loss of the paternal methylation pattern at locus D15S63 and a deletion encompassing the loci from at least D15S10 to D15S97 of paternal chromosome 15. FISH studies confirmed the deletion of 15q11-q13 region and the presence of two telomeres on all chromosomes. The proposita's father, the father's sister and their mother are all carriers of the same balanced translocation t(11;15)(q25;q13). By genomic imprinting we would expect that if the father's sister were to give birth to a child with the same unbalanced translocation as the proband, it would be affected by Angelman syndrome.
To date, a similar familial unbalanced translocation due to loss of the small chromosome 15 derivative has not been described.  相似文献   
92.
Pain in individuals with RASopathies is a neglected topic in literature. In this article, we assessed prevalence and profile of pain in a sample of 80 individuals affected by RASopathies. The study sample included individuals with Noonan syndrome (N = 42), Costello syndrome (N = 17), and cardio‐facio‐cutaneous syndrome (N = 21). A set of standardized questionnaires and scales were administered (VAS/numeric scale, r‐FLACC, Wang‐Baker scale, NPSI, BPI, NCCPC‐R) to detect and characterize acute and chronic pain and to study the influence of pain on quality of life (PEDs‐QL, SF‐36) and sleeping patterns (SDSC); revision of past medical history and multisystemic evaluation was provided. Available clinical data were correlated to the presence of pain. High prevalence of acute (44%) and chronic (61%) pain was documented in the examined sample. Due to age and intellectual disability, acute pain was localized in 18/35 individuals and chronic pain in 33/49. Muscle‐skeletal and abdominal pain was more frequently reported. The intensity of acute and chronic pain interfered with daily activities in 1/3 of the sample. Pain negatively impacted on QoL and sleeping patterns. This work documents that pain is highly prevalent in RASopathies. Future studies including subjective and objective measures of pain are required to discriminate a somatosensory abnormality from an abnormal elaboration of painful stimuli at a central level.  相似文献   
93.
94.
OBJECTIVES: To analyze the dynamics of both HIV-1-specific CD4 and CD8 T-cell responses during structured treatment interruptions (STIs) in chronically HIV-1-infected (CHI) patients and to correlate them with the viral set point achieved. METHODS: Forty-five early-stage CHI patients who were on highly active antiretroviral therapy (HAART) for at least 1 year and underwent STI were included. Plasma viral load (VL), peripheral blood mononuclear cell (PBMC) lymphoproliferative (LPR) response to HIV p24 protein, and HIV-1 epitope-specific interferon-gammarelease from CD8 T cells were measured over a minimum study period of 2 years. RESULTS: VL set point during final STI was both significantly lower than, and positively correlated to, baseline VL (P < 0.0001: mean VL reduction 0.77 log10, and r = 0.42, P = 0.004, respectively). CD4 LPRs to p24 increased significantly (P = 0.001) between day 0 of the first STI cycle and 4th STI but decreased thereafter. VL set point during final STI was significantly and negatively correlated with LPRs to p24 at both 2nd STI and 4th STI. Nevertheless, at week 52, 12 weeks after the end of the last STI, LPRs were weak and transient in all patients and were not correlated with VL set point. Moreover, the magnitude and breadth of HIV-1-specific CD8 T-cell responses increased significantly (P < 0.0001) between day 0 and week 52. The largest increases occurred during the final STI. Even though VL reached set point by week 12 of the final STI, HIV-1-specific CD8 T-cell responses did not stabilize but rather increased until the end of the follow-up and did not correlate with plasma VL (r = 0.01, P = 0.88). CONCLUSIONS: STIs do not lead to control of viral replication in CHI patients, probably due to the fact that boosted CTL responses lack strong and durable helper T-cell responses. To reset the VL set point, new approaches that effectively augment and preserve helper T-cell responses should be investigated.  相似文献   
95.
A study has been carried out in the apolipoprotein (apo) E-deficient mouse to investigate the activity of lacidipine (a calcium antagonist with antioxidant properties) in inhibiting the development of atherosclerotic lesions; of particular interest were changes in the susceptibility of low-density lipoproteins (LDL) to oxidation. Mice receiving a Western-type diet to accelerate the development of atherosclerosis were treated orally with vehicle or lacidipine at 3 or 10 mg/kg/day for 8 weeks. Lacidipine treatment (at 3 or 10 mg/kg) had no effect on the plasma lipid profile. However, a significant (P < 0.01) dose-related reduction of 43 and 50% of the aortic lesion area in respect to vehicle-treated mice was observed. Moreover, the resistance of mouse plasma LDL to undergo lipid peroxidation was significantly (P < 0.01) increased in apo E-deficient mice treated with lacidipine. The native LDL-like particle, derived from apo E-deficient mice treated with lacidipine, contained significantly lower concentrations of malonyldialdehyde than the vehicle-treated control group (P < 0.01). After exposure to human umbilical vein endothelial cells, LDL-like particle vitamin E levels (expressed as area under the curve; AUC), were significantly higher (P < 0.01) in both the 3 and 10 mg/kg lacidipine-treated groups, in comparison with the vehicle-treated control animals. We conclude that lacidipine reduced the extent of the atherosclerotic area in hypercholesterolaemic apo E-deficient mice, and that this reduction may be associated with the capacity of the drug to decrease the susceptibility of LDL to oxidation.  相似文献   
96.

Background  

Alzheimer's disease is characterized by the accumulation of neuritic plaques, containing activated microglia and β-amyloid peptides (Aβ). Fibrillar Aβ can activate microglia, resulting in production of toxic and inflammatory mediators like hydrogen peroxide, nitric oxide, and cytokines. We have recently found that microglial proliferation is regulated by hydrogen peroxide derived from NADPH oxidase. Thus, in this study, we investigated whether Aβ can stimulate microglial proliferation and cytokine production via activation of NADPH oxidase to produce hydrogen peroxide.  相似文献   
97.
Permanent neonatal diabetes mellitus (PNDM) is a rare condition characterized by severe hyperglycemia constantly requiring insulin treatment from its onset. Complete deficiency of glucokinase (GCK) can cause PNDM; however, the genetic etiology is unknown in most PNDM patients. Recently, heterozygous activating mutations of KCNJ11, encoding Kir6.2, the pore forming subunit of the ATP-dependent potassium (K(ATP)) channel of the pancreatic beta-cell, were found in patients with PNDM. Closure of the K(ATP) channel exerts a pivotal role in insulin secretion by modifying the resting membrane potential that leads to insulin exocytosis. We screened the KCNJ11 gene in 12 Italian patients with PNDM (onset within 3 months from birth) and in six patients with non-autoimmune, insulin-requiring diabetes diagnosed during the first year of life. Five different heterozygous mutations were identified: c.149G>C (p.R50P), c.175G>A (p.V59M), c.509A>G (p.K170R), c.510G>C (p.K170N), and c.601C>T (p.R201C) in eight patients with diabetes diagnosed between day 3 and 182. Mutations at Arg50 and Lys170 residues are novel. Four patients also presented with motor and/or developmental delay as previously reported. We conclude that KCNJ11 mutations are a common cause of PNDM either in isolation or associated with developmental delay. Permanent diabetes of non autoimmune origin can present up to 6 months from birth in individuals with KCNJ11 and EIF2AK3 mutations. Therefore, we suggest that the acronym PNDM be replaced with the more comprehensive permanent diabetes mellitus of infancy (PDMI), linking it to the gene product (e.g., GCK-PDMI, KCNJ11-PDMI) to avoid confusion between patients with early-onset, autoimmune type 1 diabetes.  相似文献   
98.
Pseudoachondroplasia (PSACH) is an autosomal dominant disorder characterized by disproportionate short stature and precocious osteoarthritis. Radiographic manifestations include epiphyseal, metaphyseal and vertebral abnormalities. Mutations in the cartilage oligomeric matrix protein (COMP) have been identified to cause PSACH. Most of them affect one of the eight calcium-binding domains of COMP. We describe a clinically and radiologically typical PSACH 4-year-old girl and her 31-year-old father. A novel mutation, 1345-1347CCC deletion in exon 13, of COMP was identified in both patients. The deletion would be expected to result in the loss of the conserved proline at codon 449 from the sixth calcium-binding domain. This result further supports that COMP is the only gene, discovered to date, responsible for PSACH across different populations and that the calcium-binding domains are important to the function of the normal COMP.  相似文献   
99.
Immunohistochemical and ultrastructural findings in two cases of fibrolamellar carcinoma of the liver and two cases of hepatocellular carcinoma of the common histologic type are described. Ultrastructural examination of both cases of fibrolamellar carcinoma revealed the presence of neurosecretory (NS) granules which were sparse in some cells and abundant in others. Many of the tumor cells had a distinct oncocytic appearance with abundant mitochondria. A portion of the glutaraldehyde-fixed neoplasm was processed for the uranaffin reaction (an ultrastructural cytochemical stain specific for the NS granules of neuroendocrine tissue). Abundant uranaffin-positive granules were found in the neoplastic cells of both cases of fibrolamellar carcinoma, whereas no uranaffin-positive granules were found in hepatocellular carcinoma of the common histologic type. There was no statistical difference in the mean diameter of the uranaffin-positive granules measured from both cases. Immunohisto-chemistry revealed the presence of neuron-specific enolase (NSE) and serotonin in one of the two cases of fibrolamellar carcinoma and no NSE staining in two cases of hepatocellular carcinoma of the common histologic type. These findings suggest that some liver tumors presenting histologically as fibrolamellar carcinoma may be neuroendocrine in nature.  相似文献   
100.
Monoclonal antibodies (MCA) were obtained by immunizing BALB/c mice with 99% pure granulocytes from normal donors or with a whole leukocyte suspension obtained from a chronic myelogenous leukemia (CML) patient, and then fusing the mouse spleen cells with a 315–43 myeloma cell clone. Four MCA were selected and studied using ELISA, immunofluorescence, cytotoxicity assays, and FACS analysis. Antibodies 80H.1. 80H.3. and 80H.5 (from normals) and 81H.1 (from CML) detected antigens expressed on neutrophils. Antibodies 80H.1 and 80H.3 (lgG) also reacted with monocytes but not with other blood cell subsets. Antibodies 80H.5 and 81H.1 (lgM) were cytotoxic and reacted strongly with most of the cells of the neutrophil maturation sequence. i.e., myeloblasts, promyelocytes, myelocytes, and mature granulocytes. Antibodies 80H.5 and 81H.1 also inhibited BFU-GM and CFU-E. Antigens recognized by 80H.3. 80H.5, and 81H.1 were expressed both on a proportion of cells from HL.60, KG.1, ML.1, and K562 myeloid cell lines, and on a proportion of blast cells isolated from patients with acute myelogenous leukemia. They were not found on lymphoid cell lines or lymphoid leukemia cells. These MCA recognize either late differentiation antigens expressed on mature neutrophils and monocytes (80H.1 and 80H.3) or early differentiation antigens (80H.5 and 81H.1) specific to the granulocytic lineage. They may be useful for a better definition of those antigens specific to hematopoietic stem cells and their relationship with normal or neoplastic hematopoiesis.  相似文献   
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