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101.
Autonomic failure with orthostatic and postprandial hypotension, bowel and bladder disturbances, and sexual dysfunction are frequent, disabling features in patients with the three most prevalent neurodegenerative movement disorders: Parkinson's disease (PD), dementia with Lewy bodies and multiple system atrophy (MSA), and the related neurodegenerative Lewy-body disorder characterized by isolated severe autonomic failure (pure autonomic failure, PAF). All of these disorders have in common the presence of alpha-synuclein in the cytoplasmic precipitates found in neurons in Lewy body disorders or glia in MSA. Autonomic failure with disabling orthostatic hypotension is the clinical hallmark of PAF. It may also be the initial presentation of MSA, making diagnosis difficult. Within a few years, however, MSA patients develop movement disorders, which are differentiated from PD by the paucity of unilateral resting tremor, the lack of response to levodopa, and their rapidly progressive nature, resulting in disability and death in 7 to 8 years. Moderately effective treatment is available for autonomic symptoms, but management of movement disorders remains unsuccessful. Discoveries relevant to physiology and common pathological conditions were initially made in patients with autonomic failure. Meals induce profound hypotension in these patients. Conversely, commonly used nasal decongestants can produce substantial pressor effects. Even 500 mL of water can increase blood pressure by a previously unrecognized sympathetic reflex. Residual sympathetic tone is able to induce sustained supine hypertension in MSA, because it is resolved after ganglionic blockade. These phenomena were not previously recognized because of the buffering capacity of the baroreflex, but were unmasked in autonomic failure patients.  相似文献   
102.
We analyzed the electroclinical findings in two patients with bilateral posterior agyria-pachygyria. Both patients presented with mental retardation, mild motor deficit and epilepsy. The electroclinical findings were characterized by frequent tonic or atonic generalized seizures with occasionally simple or complex partial seizures. Interictal electroencephalography (EEG) showed occipital spikes and diffuse polyspike-wave paroxysms predominantly in the posterior region. Ictal EEG showed diffuse 10-11 Hz activity. Cerebral magnetic resonance imagings (MRIs) showed thickened cortex in the parieto-occipital lobes, bilaterally and symmetrically. The volume of underlying white matter appeared reduced, and the overlying subarachnoid spaces were enlarged. The occipital horns were dilated. These findings were compatible with agyria-pachygyria of the posterior portions of the brain.In conclusion, in patients with mental retardation, mild motor deficit and epilepsy characterized by tonic or atonic generalized seizures, interictal EEG with diffuse polyspike-wave paroxysms predominantly in posterior region, posterior focal epileptilorm abnormalities and ictal diffuse 10-11 Hz activity, bilateral parieto-occipital agyria-pachygyria should be considered as a possible etiology. Magnetic resonance image is the best neuroradiological study to identify this disorder of cortical development.  相似文献   
103.
Five cases of squamous cell carcinoma arising in benign cystic teratomas found in postmenopausal patients are presented. Exhaustive tissue sampling is necessary for the discovering of malignancy in this age group. Carcinogenesis is thought to be due to local factors. Carcinoma in situ of a bowenoid type was present in two cases, which suggests an epidermal origin; however, squamous clear-cell carcinoma similar to that of the respiratory tract was also found. Prognostic parameters are discussed attaching special importance to tumor stage and the presence of tumor emboli in capsular vessels.  相似文献   
104.
OBJECTIVES: (1) Evaluate wall motion and perfusion abnormalities after reperfusion therapy of the culprit lesion, (2) delineate the ability of myocardial contrast echocardiography (MCE) to evaluate the microvasculature after reperfusion, in order to distinguish between stunning and necrosis in the risk area. METHODS: We analyzed 446 segments from 28 patients, 10 normal controls (160 segments), and 18 with a first AMI (286 segments). MCE was obtained with Optison and a two-dimensional echocardiography was performed at 3 months post acute myocardial infarction (AMI). RESULTS: In the group with AMI, we analyzed 286 segments, of which 107 had wall motion abnormalities (WMA) related to the culprit artery. Two subgroups were identified: Group I with WMA and normal perfusion (50 segments, 47%) and Group II with WMA and perfusion defects (57 segments, 53%). According to the 2D echocardiogram at 3 months, they were further subdivided into: Group IA: with wall motion improvement (stunning): 18 segments, 36%, Group IB: without wall motion improvement: 32 segments, 64%, Group IIA: with wall motion improvement: 12 segments, 21%, Group IIB: without wall motion improvement (necrosis): 45 segments, 79%. CONCLUSIONS: (1) The presence of myocardial perfusion in segments with WMA immediately after AMI reperfusion therapy predicts viability in most patients. Conversely, the lack of perfusion is not an absolute indicator of the presence of necrosis. (2) Perfusion defects allow to detect patients with thrombolysis in myocardial infarction (TIMI) 3 flow and "no-reflow" phenomenon who will not show improved wall motion in the 2D echocardiogram. However, some patients with initial no-reflow could have microvascular stunning and their regional contractile function will normalize after a recovery period.  相似文献   
105.
Previously, we reported a deficient cloning capacity of the bone marrow (BM) mesenchymal stem cells to give colony-forming unit fibroblast (CFU-F) and an inefficient confluence capacity of BM stromal cells in advanced untreated lung cancer patients (LCP) and breast cancer patients (BCP). Moreover, a decreased level of bFGF at day 7 in the conditioned media from BM CFU-F cultures was found in both cancer groups when compared to the normal range. The current study was specially undertaken, to evaluate the percentage of subconfluent fibroblasts expressing receptors (R) of interleukin-1 (IL-1), platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), transforming growth factor (TGF-beta), epidermal growth factor (EGF), and the proteins c-Fos and c-Myc in BM primary cultures from untreated LCP and BCP. An immunocytochemical study on subconfluent BM fibroblast cultures from 13 healthy patients, 16 LCP, and 8 BCP was performed, using as primary antibodies, anti-type I of IL-1 R (IL-1R-1), anti-alpha, beta chains of PDGF R (PDGFR-alpha, PDGFR-beta), anti-type I of FGF R (FGFR-I), anti-type I, II, and III of TGF-beta R (TGF-betaR-I, TGF- betaR-II, and TGF-betaR-III), anti-EGF R, anti-c-Fos, and anti-c-Myc. A diminished percentage of subconfluent fibroblasts expressing PDGFR-alpha, TGFbetaR-I, II, III, EGFR, and FGFR-I was found in LCP and BCP compared to healthy patients. A diminished percentage of subconfluent fibroblasts expressing c-Fos and c-Myc was found in patients when compared to healthy patients. The alterations we describe could help to explain the deficiency regarding the proliferative and confluence capacity of BM stroma cells in cancer patients.  相似文献   
106.
We report on two girls and one boy with clinical and electroencephalographic features of late-onset childhood epilepsy with occipital paroxysms of the "Gastaut type", showing an unusual evolution. Neurological examination and brain imaging were normal in all three. At the age of 7.5 years, eight years and ten years respectively, the three children presented with episodes of visual symptoms when awake, and in one of them, the seizures were occasionally followed by oculocephalic deviation. The interictal EEG showed bilateral occipital spike-wave activated by eye closing. In two patients, the occipital seizures had been immediately followed by typical absences, since onset; in the other patient, five months after onset. The ictal EEG showed irregular bilateral occipital spike-wave discharges during the visual symptoms, followed by generalized spike-wave activity during the typical absences. The typical absences were activated by hyperventilation; the EEG did not show continuous spikes and waves during slow sleep. These three patients, with typical electroclinical features of "Gastaut type", childhood occipital epilepsy, demonstrated an evolution which, to our knowledge, has not been previously described. We investigated whether this unusual, age-dependent evolution was due to secondary bilateral synchrony or if these electroclinical features represent two types of idiopathic epileptic syndromes in the same patients.  相似文献   
107.
CONTEXT: IGF-I deficiency may result from impairment of GH secretion or action, or from defects in IGF-I synthesis, transport, or action. Complete deficiency of the acid-labile subunit (ALS), previously described in two male patients, the only known inherited alteration in IGF-I transport, is characterized by severe circulating IGF-I and IGF binding protein (IGFBP)-3 deficiency with only mild growth retardation. OBJECTIVE: Our objective was to study the characterization, at biochemical and molecular levels, of the cause for severe circulating IGF-I and IGFBP-3 deficiency in a male patient with mild growth retardation. PATIENTS: We report an adolescent male with delayed growth and pubertal development (Tanner stage I, -2.00 sd score for height at the age of 15.3 yr), profound circulating IGF-I and IGFBP-3 deficiency, and poor response to GH treatment. RESULTS: The index case, as well as one of his brothers, and his sister were found to be compound heterozygotes for two novel IGFALS gene mutations: C540R, a missense point mutation; and S195_197Rdup, a 9-bp duplication. The parents and youngest brother were found to be carriers for one of these two mutations. The three affected siblings had marked reduction of IGF-I and IGFBP-3 levels, undetectable serum levels of ALS, inability to form ternary complexes, and moderate insulin resistance. All of them attained a normal near-adult height (between -1.0 and -0.5 sd score), which was nonetheless lower than that of their heterozygous brother. The IGF system was only modestly affected in the heterozygous carriers. CONCLUSIONS: This study confirms the critical role of ALS in forming ternary complexes and the maintenance of normal levels of IGF-I and IGFBP-3. Insulin resistance, pubertal delay in male patients, and poor GH responsiveness seem to be frequent findings in ALS deficiency. However, haploinsufficiency of the IGFALS gene has no discernible clinical effects with only modest impact on the IGF system.  相似文献   
108.
Block copolymer micelles, containing dichloro(1,2-diaminocyclohexane)platinum(II) (DACHPt), the oxaliplatin parent complex, were prepared through polymer-metal complex formation of DACHPt with poly(ethylene glycol)-poly(glutamic acid) block copolymer [PEG-P(Glu)] in distilled water. By dynamic light scattering (DLS) measurement, the micelle size was determined to be 40 nm with narrow distribution. The release of platinum complexes from the micelle core was measured in phosphate buffer saline (pH 7.4) at 37 degrees C. DACHPt-loaded micelle showed a sustained release rate of platinum after an induction period of 12 h. In the same conditions, the kinetic stability of DACHPt-loaded micelle was measured. The micelle was found to be very stable, keeping the initial size, for 240 h. Against murine colon adenocarcinoma 26 (C-26) cells, DACHPt-loaded micelle exhibited considerable in vitro cytotoxicity, lower than oxaliplatin but increasing with exposure time as a result of the release of platinum complexes from the micelle. In vivo biodistribution assay performed on tumor-bearing mice demonstrated that the micelle showed prolonged blood circulation due to its high stability and high tumor accumulation for a prolonged time.  相似文献   
109.

Background

The contraceptive efficacy of emergency contraceptive pills containing levonorgestrel (LNG-EC) has been estimated in most previous studies by judging the day of ovulation from presumptive menstrual cycle data, thus providing poorly reliable estimates.

Methods

In the present study, the efficacy of LNG-EC was determined in 393 cycles by dating ovulation on the basis of reliable hormonal and ovarian parameters validated by a database constructed in a separate study. In addition, the efficacy was determined separately for cycles in which LNG-EC was given before or after ovulation.

Results

For the 148 women who had sexual intercourse during the fertile days, the overall accumulated probability of pregnancy was 24.7, while altogether 8 pregnancies were observed. Thus, the overall contraceptive efficacy of LNG-EC was 68%. Among the 103 women who took LNG-EC before ovulation (days −5 to −1), 16 pregnancies were expected and no pregnancy occurred (p<.0001). Among the 45 women who took LNG-EC on the day of ovulation (day 0) or thereafter, 8 pregnancies occurred and 8.7 were expected (p=1.00). These findings are incompatible with the inhibition of implantation by LNG-EC in women. The same cases were also analyzed using the presumptive menstrual cycle data, and important discrepancies were detected between the two methods.

Conclusion

The efficacy of LNG-EC has been overestimated in studies using presumptive menstrual cycle data. Our results confirm previous similar studies and demonstrate that LNG-EC does not prevent embryo implantation and therefore cannot be labeled as abortifacient.  相似文献   
110.
The acute-phase febrile responses of the inbred Lewis (LEW) and Fischer 344 (F344) rat strains and their parent Sprague-Dawley (S-D) strain to immune challenge with lipopolysaccharide (LPS) were compared. LEW and S-D males and females displayed a biphasic febrile response with a markedly attenuated second phase in F344 rats. At 2 h after LPS (50 microg/kg), corticosterone was significantly higher in F344 than in LEW rats, but serum interleukin-1beta was higher only in F344 than LEW males. These data suggest that the greater LPS-induced corticosterone response of F344 rats mediates differences between febrile responses of F344 and LEW males and females.  相似文献   
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