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991.
CONTEXT: Mutations of the HRPT2 gene have recently been implicated in the development of parathyroid carcinoma. OBJECTIVE: The objective of this study was early diagnosis of parathyroid tumor in a family with germline HRPT2 mutation. PATIENTS, METHODS, AND RESULTS: In a 40-yr-old male previously treated for parathyroid atypical adenoma, we screened the 17 translated HRPT2 exons and their exon-intron boundaries and found a germline frameshift mutation in exon 7 (685delAGAG) predicting a premature stop codon at nucleotides 767-769. Nine family members (age, 33.9 +/- 19.8 yr, mean +/- SD) also carry the mutation, but eight have had normal serum calcium. Biochemical and ultrasonographic evaluation uncovered a 27-yr-old hypercalcemic carrier niece with an atypical parathyroid adenoma, and a 43-yr-old normocalcemic carrier sister was found by ultrasonography to have an extrathyroidal nodule, which proved to be parathyroid carcinoma. The index case, 12 yr after surgery, was normocalcemic, but ultrasonography revealed an extrathyroidal nodule in the contralateral hemithyroid tissue that proved to be atypical adenoma. CONCLUSIONS: Our report confirms that germline mutations of HRPT2 gene may be associated with multiple parathyroid neoplasms. Our experience suggests that longitudinal surveillance by serum biochemistry alone may not be 100% sensitive, and addition of routine neck ultrasonography is a readily accepted adjunct that may facilitate earlier disease detection in some families.  相似文献   
992.
BACKGROUND: Cardiovascular risk factor research has recently broadened its focus based on new data indicating the benefits of low risk, i.e. favorable levels of all major risk factors. The aims of this study were to assess further the relation of low risk to coronary heart disease risk, and implications for prevention. DESIGN: We conducted a prospective population-based Italian study, of 7438 men and 13 009 women aged 35-69 years, with a mean follow-up of 10.4 years and validated first coronary events. METHODS: Baseline coronary heart disease risk was classified into three categories: low risk; unfavorable but not high risk; and high risk. To analyze the relation of these risk profiles to coronary heart disease incidence, age-adjusted, sex-averaged coronary heart disease incidence was calculated for persons free of coronary heart disease and stroke, stratified as baseline low risk, unfavorable but not high risk or high risk. To assess the independent relationship of individual risk factors to coronary heart disease incidence, multivariate proportional hazards models were computed for combinations of risk factors. RESULTS: Only 2.7% of participants met low risk criteria; 81.4% were high risk. Age-adjusted coronary heart disease incidence for the whole cohort was 37.1 out of 10000 person-years (men 59.0; women 15.3). No coronary heart disease events occurred in low-risk men, only two in low-risk women. For women and men who were not high risk, the age-sex standardized coronary heart disease rate was 62% lower than for high-risk participants. Blood pressure, need for antihypertensive medication, smoking, hyperglycemia, diabetes, total and high-density lipoprotein cholesterol were independently related to coronary heart disease risk. CONCLUSIONS: Favorable levels of all modifiable readily measured risk factors - rare among Italian adults - assure minimal coronary heart disease risk. Population-wide prevention is needed, especially improved lifestyles, to increase the proportion of the population at low risk.  相似文献   
993.
Background: At the Istituto di Clinica Medica Generale e Cardiologia (Florence, Italy), the widespread use of percutaneous coronary intervention (PCI) has markedly changed the hospital course of patients with acute myocardial infarction (AMI). These patients are typically transferred to the coronary care unit (CCU) only after primary PCI, whereas during the thrombolytic era, patients were first admitted to CCU before reperfusion. Objectives and Methods: The incidence, timing and setting of complications from symptom onset to hospital discharge in 689 consecutive AMI patients undergoing PCI were evaluated. Results: Ventricular fibrillation occurred in 11% of patients, and most episodes (94.7%) occurred before or during PCI. Of all patients, 6.3% developed complete atrioventricular block (CAVB), and in 86.3% of these cases, the CAVB occurred before or during PCI; in 94.5%, a CAVB resolution occurred in the catheterization laboratory (CL). Thirty-one patients (4.5%) had impending shock on admission to the CL. Cardiogenic shock developed in 2 9 patients (4.2%), mostly in the prehospital phase or in the CL. Only four patients (less than 1%) developed cardiogenic shock later during their hospital course. Similarly, circulatory and ventilatory support, as well as temporary pacing and cardiac defibrillation, were used mostly in the prehospital phase or in the CL. During the CCU stay, 45 patients (6.5%) had hemorrhagic or vascular complications, and the incidence of post-PCI ischemia and early reocclusion of the culprit vessel were low (2.1% and 0.6%, respectively). Thus, cardiac complications usually associated with AMI were observed mainly before hospital admission or in the CL during the reopening of the target vessel. These complications were rarely observed after a successful PCI. Conclusions: For AMI patients, the CL is not only the site of PCI, it is also where most life-threatening cardiac complications are observed and treated.  相似文献   
994.
Early prediction of respiratory muscle involvement and chronic hypoventilation (CH) in amyotrophic lateral sclerosis (ALS) patients can help to plan mechanical ventilatory aids and palliative care interventions well before respiratory failure occurs. To describe the natural history of the progressive pulmonary dysfunction leading to CH, and to identify potential parameters associated with its development in ALS, we prospectively followed 38 ALS patients up to 26 months, starting from their first presentation at our Clinic. At study entry, median FVC was 87% (interquartile range: 72-104%) and declined by 10% after 6 months (range: 2-49%), showing a very high inter-patient variability. Over the 26-months follow-up, 19 patients (50%) presented CH in the first 12 months, and eight patients (21%) developed CH in the remaining 14 months of the study. The remaining 29% of patients did not show signs of CH during the whole period of observation. In the Cox model, the category of disease progression (rapid vs. intermediate and slow), assessed using the Appel ALS Rating Scale (AARS) in the first 3 months after presentation, was the only variable associated with a significantly increased likelihood of CH. We conclude that CH can occur within 1 year from presentation in a great proportion of patients, independently from their initial respiratory status. Including the patients in specific categories of early disease progression, as assessed with the AARS, could be a sensitive method to identify patients with different risk of developing CH, and may help physicians to more efficiently plan the frequencies of respiratory evaluations, initiate mechanical ventilation and discuss advance directives with the patients and their caregivers.  相似文献   
995.
We reviewed the clinical, microbiologic, and outcome characteristics of 72 patients with human immunodeficiency virus (HIV)-associated histoplasmosis (4 newly described) reported in Europe over 20 years (1984-2004). Seven cases (9.7%) were acquired in Europe (autochthonous), whereas the majority involved a history of travel or arrival from endemic areas. The diagnosis of progressive disseminated histoplasmosis (PDH) was made during life in 63 patients (87.5%) and was the acquired immunodeficiency syndrome (AIDS)-presenting illness in 44 (61.1%). Disease was widespread in 66 patients (91.7%) and localized in 6 (8.3%), with the skin being the most frequent site of localized infection. Overall skin involvement was reported in 47.2% of the patients regardless of whether histoplasmosis was acquired in Africa or South America. Reticulonodular or diffuse interstial infiltrates occurred in 52.8%. The diagnosis was made during life by histopathology plus culture in 44 patients (69.8%), histopathology alone in 18 (28.5%), and culture alone in 1 (1.5%). During the induction phase amphotericin B and itraconazole (74.6%) were the single most frequently used drugs. Both drugs were also used either in combination (10.2%) or in sequential therapy (11.8%). Cumulative mortality rate during the induction phase of treatment was 15.2%. Overall, 37 patients died (57.8%); death occurred early in the course in 18 (28.1%). Seven of 40 patients (17.5%) who responded to therapy subsequently relapsed. Autopsy data in 13 patients confirmed the widespread disseminated nature of histoplasmosis (85%) among AIDS patients with a median of 4.5 organs involved. The results of the present report highlight the need to consider the diagnosis of PDH among patients with AIDS in Europe presenting with a febrile illness who have traveled to or who originated from an endemic area.  相似文献   
996.
Thyroid cancer is the most common endocrine malignancy. More than 90% of primary thyroid cancers are differentiated papillary or follicular types. The treatment of differentiated thyroid carcinoma (DTC) consists of total thyroidectomy and radioactive iodine ablation therapy, followed by L-thyroxine therapy. The extent of initial surgery, the indication for radioiodine ablation therapy and the degree of TSH-suppression are all issues that are still being debated cancers are in relation to the risk of recurrence. Total thyroidectomy reduces the risk of recurrence and facilitates (131)I ablation of thyroid remnants. The aim of radioiodine ablation is to destroy any normal or neoplastic residuals of thyroid tissue. These procedures also improve the sensitivity of thyroglobulin (Tg) as a marker of disease, and increase the sensitivity of (131)I total body scan (TBS) for the detection of persistent or recurrent disease. The aim of TSH-suppressive therapy is to restore euthyroidism and to decrease serum TSH levels, in order to reduce the growth and progression of thyroid cancer. After initial treatment, the objectives of the follow-up of DTC is to maintain adequate thyroxine therapy and to detect persistent or recurrent disease through the combined use of neck ultrasound (US) and serum Tg and (131)I TBS after TSH stimulation. The follow-up protocol should be adapted to the risk of recurrence. Recent advances in the follow-up of DTC are related to the use of recombinant human TSH (rhTSH) in order to stimulate Tg production and the ultrasensitive methods for Tg measurement. Undetectable serum Tg during TSH suppressive therapy with L-T4 does not exclude persistent disease, therefore serum Tg should be measured after TSH stimulation. The results of rhTSH administration and L-thyroxine therapy withdrawal are equivalent in detecting recurrent thyroid cancer, but the use of rhTSH helps to avoid the onset of hypothyroid symptoms and the negative effects of acute hypothyroidism on cardiovascular, hepatic, renal and neurological function. In low-risk DTC patients serum Tg after TSH stimulation, together with ultrasound of the neck, should be used to monitor persistent disease, avoiding diagnostic TBS which has a poor sensitivity. These recommendations do not apply when Tg antibodies are present in the serum, in patients with persistent or recurrent disease or limited thyroid surgery. Low-risk patients may be considered to be in remission when undetectable Tg after TSH stimulation and negative US evaluation of the neck are present. On the contrary, detectable Tg after TSH stimulation is an indicator in selecting patients who are candidates for further diagnostic procedures.  相似文献   
997.
To investigate the mechanisms of anaphylactoid reactions to radiocontrast media, in vitro mediator release induced by three iodinated contrast agents was examined using peripheral blood basophils and mast cells purified from human lung parenchyma, heart, and skin tissues. Three iodinated contrast agents, sodium and meglumine salts of ioxaglic acid, sodium and meglumine salts of ioxithalamic acid, and ioversol, were incubated with basophils purified from peripheral blood and human mast cells isolated and purified from different anatomical sites. Release of preformed (histamine and tryptase) and de novo synthesized mediators (prostaglandin D2 and leukotriene C4) into the supernatans was determined at various contrast medium concentrations after incubation for 60 min. Ioxaglate (0.2–0.3 M), ioxithalamate (0.3–0.5 M), and to a lesser extent ioversol (0.3–0.5 M) induced histamine release from basophils in a concentration-dependent manner. All three induced the release of preformed mediators (histamine and tryptase) from human lung, but not from skin mast cells. They also induced histamine and tryptase release from human heart mast cells. However, they did not induce the de novo synthesis of leukotriene C4 or prostaglandin D2 from human basophils or any type of mast cell examined. Cross-linking of IgE by anti-IgE induced the release of leukotriene C4 or prostaglandin D2 from human basophils or mast cells. Mannitol, an osmotic stimulus, induced the release of histamine from human basophils, but to a lesser extent from mast cells. These results show that different contrast media can differ in their ability to release mediators from enriched preparations of human basophils and mast cells. The three contrast agents examined act on basophils and mast cells as incomplete secretagogues, causing the release of preformed mediators, but not the de novo synthesis of chemical mediators. It may be useful to measure plasma tryptase levels to detect adverse reactions caused by iodinated radiographic contrast materials.  相似文献   
998.
AIMS: Ostium secundum atrial septal defect (osASD) is one of the most common cardiac malformations. Few data are available on the familial recurrence of congenital heart disease (CHD), in particular, in a large group of patients with isolated osASD. The aim is to investigate the familial recurrence of CHD in up to third-degree relatives from a large sample of consecutively enrolled patients with osASD, taking into account the influence of degree of relatedness (as number of relatives). METHODS AND RESULTS: From January 1998 to December 2002, we enrolled 583 patients with osASD and 408 healthy subjects, referred to our tertiary centre. We hypothesized that a positive family history required at least one relative with CHD to constitute a risk factor. In this model of analysis, the null hypothesis is a similar familial history between cases and controls. Among 583 patients with osASD, 109 (19%) had at least one relative with CHD. Among the 408 healthy subjects studied, only 23 (6%) had a family history of CHD. A familial recurrence of CHD was demonstrated in 72 of 312 (23%) patients with isolated osASD and in 37 of 271 (13.6%) patients with non-isolated osASD. Familial recurrence of isolated osASD was demonstrated in 22 of 312 patients (7%) with an isolated osASD and only in six of 271 patients (2.2%) with non-isolated osASD. The familial recurrence risk of isolated osASD in patients with isolated osASD was higher in sibs, especially in sisters (33.3%). CONCLUSION: This study underscores the role of genetic factors in the determination of CHD, particularly osASD. Our results could represent the basis for further studies to calculate a 'value of family history' to adapt the familial recurrence to the real size of each family group. In this way, we could select families with a 'tendency' to develop CHD, particularly osASD. In these families, we could analyse the genetic pattern to establish abnormalities and the bases of CHD.  相似文献   
999.
The phosphatidyl-inositol 3 kinase (PI3k)/Akt pathway has been implicated in childhood acute lymphoblastic leukemia (ALL). Because rapamycin suppresses the oncogenic processes sustained by PI3k/Akt, we investigated whether rapamycin affects blast survival. We found that rapamycin induces apoptosis of blasts in 56% of the bone marrow samples analyzed. Using the PI3k inhibitor wortmannin, we show that the PI3k/Akt pathway is involved in blast survival. Moreover, rapamycin increased doxorubicin-induced apoptosis even in nonresponder samples. Anthracyclines activate nuclear factor kappaB (NF-kappaB), and disruption of this signaling pathway increases the efficacy of apoptogenic stimuli. Rapamycin inhibited doxorubicin-induced NF-kappaB in ALL samples. Using a short interfering (si) RNA approach, we demonstrate that FKBP51, a large immunophilin inhibited by rapamycin, is essential for drug-induced NF-kappaB activation in human leukemia. Furthermore, rapamycin did not increase doxorubicin-induced apoptosis when NF-kappaB was overexpressed. In conclusion, rapamycin targets 2 pathways that are crucial for cell survival and chemoresistance of malignant lymphoblasts--PI3k/Akt through the mammalian target of rapamycin and NF-kappaB through FKBP51--suggesting that the drug could be beneficial in the treatment of childhood ALL.  相似文献   
1000.
Vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) are regulatory neuropeptides of the hypothalamus-hypophyseal-adrenal axis, acting via the common receptors VPAC(1) and VPAC(2) and the selective PACAP receptor PAC(1). In the adrenal glands of the Italian wall lizard, Podarcis sicula, the presence of VIP in chromaffin cells, and the VIP-stimulated release of catecholamine and aldosterone in vivo, was previously shown. To examine the localization of both peptides and receptors and their mRNAs in the adrenal gland of P. sicula, immunohistochemistry and in situ hybridization were performed: PACAP and its mRNA were detected in chromaffin cells, VPAC(1) was found associated with steroidogenic tissue, VPAC(2) and PAC(1) with chromaffin tissue. Using 'far western blot' technique, we showed the presence of specific binding sites for VIP/PACAP in the adrenal glands of the lizard. The effects of both VIP and PACAP on the adrenal cells of the lizard were examined in vitro in adrenal cell co-cultures: both VIP and PACAP enhanced catecholamine, corticosterone and aldosterone release from adrenal cell co-culture in a time- and dose-dependent manner. The catecholamine release was inhibited by PAC(1) antagonist and in VPAC(2) immunoneutralized adrenal cells. The effects of VIP and PACAP on aldosterone secretion were counteracted by VPAC(1) antagonist administration in vitro. Corticosterone secretion elicited by VIP was not blocked by VPAC(1) antagonist, while the PACAP-induced release of corticosterone was blocked by the antagonist. Overall, our investigations indicate that these neuropeptides of the secretin superfamily can act not only as neurotransmitters but also as autocrine and paracrine regulators on chromaffin and cortical cells, being important mediators of the non-cholinergic system in the lizard adrenal gland.  相似文献   
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