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11.
In 30 consecutive patients with Prinzmetal's angina pectoris, the antiischemic effect of felodipine, a new long-acting vasoselective calcium antagonist, administered at doses of 10 and 20 mg once daily was compared with that of the wellestablished therapeutic regimen with nifedipine administered at a dose of 20 mg 4 times daily. Twenty-four-hour Holter monitoring was performed during a 2-day placebo run-in and at the end of each of 3 consecutive 6-day periods during which the 3 active treatments were administered in randomized sequence. Three patients withdrew, whereas 27 completed the study. The therapeutic regimens tested proved to be similarly effective; primary end points (ischemic episodes recorded by Holter monitoring, and anginal attacks reported on diary cards) occurred in 5 patients (19%) during nifedipine treatment, and in 7 (26%) and 3 (11%) during felodipine treatment with 10 and 20 mg, respectively (p = not significant). The distribution of residual ischemic episodes demonstrated that treatment with felodipine once daily provides 24-hour antiischemic protection. Twenty-six patients were followed up with 20 mg of felodipine once daily for a mean of 6 ± 5 months, and 21 of them (81%) remained free of symptoms and Holter-recorded ischemic attacks. It is concluded that for Prinzmetal's angina pectoris, 24-hour antiischemic protection may be achieved with administration of felodipine once daily. The availability of a simplified therapeutic approach may constitute a real advantage in terms of patient compliance and improving the quality of life.  相似文献   
12.
To investigate the incidence of myocarditis, 30 patients, with unexplained congestive heart failure, underwent endomyocardial biopsy. For each case three to five samples were examined on light and electron microscopy. Inflammatory infiltrates and injury to adjacent myocytes consistent with myocarditis were detected in 3 of the 30 cases (10%). Changes attributable to cardiomyopathy were found in the remaining 27 cases. Two of the three patients with biopsy-proven myocarditis were treated with prednisone and azathioprine. Their control biopsies six months later showed interstitial fibrosis and absence of inflammatory infiltrates. They clinically improved but hemodynamic and angiocardiographic patterns failed to show the expected improvement. The third patient affected by myocarditis died two weeks later. In conclusion: in our series of patients with unexplained congestive heart failure, the incidence of biopsy-proven myocarditis resulted low (10%). The results of the immunosuppressive treatment in two patients with myocarditis were unconclusive. Therefore the effectiveness of such therapy should be confirmed in a larger number of patients.  相似文献   
13.
Three patients complained of spontaneous and exertional chest pain, both associated with S-T segment depression in anterior electrocardiographic leads. In each, coronary spasm was demonstrated on coronary arteriography during a spontaneous attack of pain. Coronary arteriograms taken during exercise-induced angina did not show evidence of spastic obstruction; this suggests that exercise-induced chest pain and S-T segment depression were secondary to the increase in oxygen requirements rather than to a sudden decrease in coronary blood flow. Thus, two pathogenetic mechanisms coexisting in the same patient may cause chest pain associated with subendocardial ischemia.  相似文献   
14.
Studies on the interactions between SARS-CoV-2 and humoral immunity are fundamental to elaborate effective therapies including vaccines. We used polychromatic flow cytometry, coupled with unsupervised data analysis and principal component analysis (PCA), to interrogate B cells in untreated patients with COVID-19 pneumonia. COVID-19 patients displayed normal plasma levels of the main immunoglobulin classes, of antibodies against common antigens or against antigens present in common vaccines. However, we found a decreased number of total and naïve B cells, along with decreased percentages and numbers of memory switched and unswitched B cells. On the contrary, IgM+ and IgM plasmablasts were significantly increased. In vitro cell activation revealed that B lymphocytes showed a normal proliferation index and number of dividing cells per cycle. PCA indicated that B-cell number, naive and memory B cells but not plasmablasts clustered with patients who were discharged, while plasma IgM level, C-reactive protein, D-dimer, and SOFA score with those who died. In patients with pneumonia, the derangement of the B-cell compartment could be one of the causes of the immunological failure to control SARS-Cov2, have a relevant influence on several pathways, organs and systems, and must be considered to develop vaccine strategies.  相似文献   
15.
Dolutegravir (DTG) is currently one of the most used Integrase inhibitors (INI) in antiretroviral therapies (ARV) in both naïve and experienced people living with HIV (PLWHIV). We analyzed a multicenter cohort of PLWHIV, both naïve and experienced, starting an ARV including DTG. We enrolled 3775 PLWHIV: 2763 (73.2%) were males, with a median age of 50 years. During 9890.7 PYFU, we observed 930 discontinuations (9.4 per 100 PYFU). Estimated probabilities of maintaining DTG at three and five years were 75.1% and 67.2%, respectively. Treatment-naïve pts showed a lower probability of maintaining DTG at three and five years compared to treatment-experienced PLWHIV (log-rank p < 0.001). At a multivariate analysis, a longer time of virological suppression (aHR 0.994, p < 0.001) and having experienced a previous virological failure (aHR 0.788, p = 0.016) resulted protective against DTG discontinuation. Most discontinuations (84.0%) happened within the first 12 months of DTG initiation, in particular, 92.2% of discontinuations due to neuropsychiatric toxicity were observed in the first year. Our data confirm the overall good tolerability of DTG in clinical practice, with a low rate of discontinuations. CNS toxicity resulted the main reason for DTG discontinuation, with most related interruptions happening in the first year from DTG introduction.  相似文献   
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BACKGROUND: HIV infection per se and HAART can alter mitochondrial functionality, leading to a decrease in mitochondrial DNA content. OBJECTIVE: To evaluate whether treatment interruption monitored by CD4 cell count can restore mitochondrial DNA content in peripheral blood lymphocytes. METHODS: Mitochondrial DNA content was measured in platelet-free CD4 and CD8 T cells by real-time polymerase chain reaction; flow cytometry was used to identify and quantify activated CD4 and CD8 T lymphocytes. RESULTS: The 30 patients had been treated for a mean of 107 months (range, 27-197). Median CD4 cell count at discontinuation was 702 cells/microl (range, 547-798). Median observational time from HAART discontinuation was 11.3 months (range, 4-26). Discontinuation of treatment provoked significant increases in mitochondrial DNA in CD8 T cells, which started only 6 months after therapy discontinuation [5.12 copies/cell per month from 0 to 6 months (P = 0.37) and 26.96 copies/cell per month from 6 to 12 months (P < 0.0001)]. CONCLUSIONS: This study is the first showing that mitochondrial DNA content can increase in peripheral blood lymphocytes during treatment interruption, but only after at least 6 months of interruption. Consequently, interruptions of shorter periods, whether by clinician or patient decision, are unlikely to allow restoration of mitochondrial DNA and so decrease HAART-related toxicity.  相似文献   
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The recent development of the duplex-Doppler technique, which combined real-time US with pulsed Doppler flowmetry, has allowed the flowmetric hemodynamic study of large abdominal vessels. As yet, however, both accuracy and possible applications of this method in the study of portal hypertension have not been fully investigated. This study was aimed at assessing whether or not the combined use of Doppler flowmetry and bidimensional US is able to detect portal hypertension in patients with liver cirrhosis (LC), and could therefore represent a valid alternative to endoscopic, angiographic, and direct pressure measurement techniques. Twenty-six patients with LC and 25 control patients were studied with a strictly standardized method; portal hypertension was detected in the patients with LC by EGDS and laparoscopy. The results demonstrated pulsed duplex-Doppler US to be able to detect portal hypertension in 92.4% of LC patients, with 2 false negatives only (7.6%). The difference in the flowmetric data of normal and LC patients was highly significant (p less than 0.001 Student's t test). In conclusion, duplex-Doppler US can be considered as a valid technique to detect portal hypertension in LC patients, and can thus be used as an alternative to more invasive techniques of general use in clinics.  相似文献   
20.
We studied experimental models capable of showing muscle degeneration and subsequent regeneration and observed the changes in calmitine, calcium uptake and calcium concentration in mitochondria during these processes. The results presented here are based on the study of mitochondria of mouse skeletal muscle after a single intramuscular injection of chlorpromazine. This drug induces myotoxic effects followed by muscle regeneration. Our results show that the muscle degeneration process, as shown by histological studies, was associated with some changes in mitochondria: a decrease in calmitine, a calcium overload and a decrease in calcium uptake; the subsequent regeneration process was associated with an increase in calmitine, a decrease in calcium concentration and an increase in calcium uptake, these 3 parameters returning to normal values. It seems that there is a correlation between a decrease in calmitine and muscle degeneration, and an increase in calmitine and muscle regeneration, as shown by our biochemical and histological observations.  相似文献   
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