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1.  Full-dose intra-operative radiotherapy with electrons (ELIOT) during breast-conserving surgery: experience with 1246 cases 
Background:
Previous studies showed that after breast-conserving surgery for breast cancer, radiotherapy may be applied to the portion of the breast where the primary tumour was removed (partial breast irradiation (PBI), avoiding the irradiation of the whole breast. We developed a procedure of PBI consisting of a single high dose of radiotherapy of 21 Gy with electrons equivalent to 58–60 Gy in fractionated doses, delivered during the surgical session by a mobile linear accelerator, positioned close to the operating table.
Patients and methods:
From July 1999 to December 2006, 1246 patients with primary carcinoma of less than 2.5-cm maximum diameter, mostly over 48 years, were treated with electron intra-operative radiotherapy (ELIOT) at a single dose of 21 Gy.
Results:
After a follow-up from 0.3 to 94.7 months (median 26), 24 (1.9%) patients showed a local recurrence and 22 developed distant metastases. Sixteen patients died, seven from breast carcinoma and nine from others causes. The five-year crude survival was 96.5%. Six (0.5%) developed severe breast fibrosis, which resolved in 2–3 years. An additional 40 patients suffered for mild fibrosis. Cosmetic results were good.
Conclusions:
Electron intra-operative radiotherapy is a safe method for treating conservatively operated breasts and avoids the long period of post-operative radiotherapy, greatly improving the quality of life and reduces the cost of radiotherapy. ELIOT markedly reduces the radiation to normal surrounding tissues and deep organs. Results on short- and medium-term toxicity are good. Data on local control are encouraging.
doi:10.3332/eCMS.2008.65
PMCID: PMC3234040  PMID: 22275962
2.  Erythromycin resistance in Streptococcus pyogenes in Italy. 
Emerging Infectious Diseases  2000;6(2):180-183.
In a prospective study of acute pharyngitis in Italian children, 69 (38.3%) of 180 isolates of Streptococcus pyogenes were resistant to macrolides. S. pyogenes was eradicated in 12 (63.1%) of 19 patients with erythromycin-resistant S. pyogenes treated with clarithromycin and in 22 (88%) of 25 patients with erythromycin-susceptible strains. The constitutive-resistant phenotype was correlated with failure of macrolide treatment.
PMCID: PMC2640849  PMID: 10756153
4.  Penetration of dapsone into pulmonary lining fluid of human immunodeficiency virus type 1-infected patients. 
We studied the penetration of dapsone into the epithelial lining fluid (ELF) of sixteen human immunodeficiency virus type 1-infected patients who had received the drug at a dose of 100 mg twice weekly as primary prophylaxis for Pneumocystis carinii pneumonia. Bronchoscopy, bronchoalveolar lavage (BAL), and venipuncture were performed for each patient at a specific time after administration of the last dose of dapsone. Dapsone concentrations in plasma and BAL were determined by high-performance liquid chromatography. The apparent volume of ELF recovered by BAL was determined by using urea as an endogenous marker. The mean concentrations of dapsone in ELF at 2 h (five patients), 4 h (three patients), 12 h (two patients), 24 h (three patients), and 48 h (three patients) were 0.95, 0.70, 1.55, 0.23, and 0.45 mg/liter, respectively, while concentrations in plasma were 1.23, 0.79, 1.31, 0.83, and 0.18 mg/liter, respectively. Dapsone concentrations in ELF were 76, 79, 115, 65, and 291% of those observed in plasma at the same times, respectively. These data show that dapsone is well distributed into ELF and that a twice-weekly 100-mg prophylactic regimen results in sustained concentrations in this compartment.
PMCID: PMC163854  PMID: 9145873
5.  Population pharmacokinetics of dapsone administered biweekly to human immunodeficiency virus-infected patients. 
Antimicrobial Agents and Chemotherapy  1996;40(12):2743-2748.
The population pharmacokinetics of dapsone were examined in human immunodeficiency virus-infected patients receiving dapsone at a dosage of 100 mg twice weekly for the prevention of Pneumocystis carinii pneumonia. Nonlinear mixed-effect modeling was used to determine the best pharmacostatistical model for the data. A one-compartment open model with first-order absorption and elimination was used as the structural pharmacokinetic model. Several covariates were tested for their influence on pharmacokinetic parameters. Rifampin was found to increase the values of clearance/bioavailability (CL/F) and volume of distribution/ bioavailability (V/F) by approximately 70%. CL/F and V/F were 1.83 liters/h and 69.6 liters, respectively, for patients not taking rifampin. The effect of rifampin on the pharmacokinetic parameters of dapsone was appreciably less than expected on the basis of studies with healthy volunteers. Increased bilirubin levels were associated with a significant decrease in the absorption rate constant (Ka). However, this finding may be considered clinically irrelevant because the post hoc Bayesian estimates of Ka for patients with high bilirubin levels ( > 1.2 mg/dl) were at the lower bound of the values for patients with normal bilirubin levels. The value of Ka was 0.957 h-1 for a patient with a bilirubin level of 0.7 mg/dl. After inclusion of covariates in the model, the interpatient variability was 35% for CL/F, not significant for V/F, and 85% for Ka. Simulation of plasma concentration-versus-time curves indicated that the administration of 100 mg of dapsone biweekly is associated with sustained dapsone levels in the plasma of the majority of the patients. Dosage adjustments for patients concomitantly treated with rifampin may be necessary.
PMCID: PMC163614  PMID: 9124833
6.  Protein binding of clindamycin in sera of patients with AIDS. 
Patients with AIDS have altered pharmacokinetics of clindamycin compared with those of healthy control subjects. In an attempt to better understand these differences, we undertook a study of protein binding of clindamycin in sera of patients with AIDS. Fifteen patients with AIDS and 15 healthy volunteers were given a single 600-mg dose of clindamycin orally and intravenously, and serum samples were collected at three time points corresponding to high, midpoint, and low clindamycin concentrations. Protein binding was determined by ultrafiltration, and total and unbound clindamycin concentrations were measured with a gas chromatography assay. AIDS patients had alpha 1-acid glycoprotein values approximately twice those of healthy volunteers (mean +/- standard deviation, 103 +/- 27 versus 61 +/- 11 mg/dl; P = 0.001). Overall, serum protein binding levels were higher in AIDS patients (mean +/- standard deviation, 83 +/- 7 versus 78% +/- 8%; P = 0.0001), which is likely the result of increased alpha 1-acid glycoprotein levels in these patients. Total concentrations of clindamycin in plasma were significantly higher in AIDS patients at most time points studied, while unbound serum clindamycin concentrations did not differ among the groups at each sampling time after both oral and intravenous dosing. Increased protein binding may partly explain the altered pharmacokinetic disposition of clindamycin in AIDS patients; however, other factors cannot be excluded.
PMCID: PMC163278  PMID: 8723453
7.  Pharmacokinetics of dapsone in human immunodeficiency virus-infected children. 
Dapsone, administered at various doses and schedules, has been proven to be a safe and effective alternative to trimethoprim-sulfamethoxazole for prevention of Pneumocystis carinii pneumonia (PCP) in adults with human immunodeficiency virus (HIV) infection. Dapsone is also recommended by the Centers for Disease Control for PCP prophylaxis in HIV-infected children. However, the suggested dosage regimen is based upon clinical experience with children with leprosy and dermatitis herpetiformis rather than pharmacokinetic and pharmacodynamic data obtained from the target patient population. In order to determine a rational dosage regimen that could be tested in clinical studies aimed at the evaluation of dapsone for the prevention of PCP in HIV-infected children, we studied the pharmacokinetics of dapsone following a 2-mg/kg of body weight oral dose in twelve HIV-positive children aged 9 months to 9 years. Plasma was collected at the following times after dapsone administration: 0, 2, 4, 6, 12, 24, 48, 72, and 96 h. The levels of dapsone in plasma were determined by high-performance liquid chromatography. Data were analyzed by noncompartmental methods. Expressed as means +/- standard deviations (ranges), the pharmacokinetic parameters were as follows: peak concentration in plasma, 1.12 +/- 0.48 (0.44 to 1.81) mg/liter; time to peak concentration in plasma, 3.8 +/- 1.3 (2 to 6) h; half-life at elimination phase, 24.2 +/- 7.1 (14.4 to 35.0) h; clearance from plasma divided by bioavailability (CL/F), 1.15 +/- 0.67 (0.37 to 2.63) ml/min/kg; and volume of distribution divided by bioavailability (V/F), 2.25 +/- 1.20 (1.00 to 4.57) liters/kg. Oral CL correlated negatively with age (r = 0.614 and P = 0.034), as did V (r = 0.631 and P = 0.028). As a consequence of the high interindividual variability in growth retardation, pharmacokinetic parameters correlated with measures of body development better than they did with age (e.g., for CL/F to height, r = 0.765 and P = 0.004, and for V/F to height, r = 0.748 and P = 0.005). Since oral CL from plasma and V were positively and highly correlated (r = 0.898 and P = 0.0001), a lower absolute F may be the cause, in part, of higher values for CL/F and V/F in smaller children. The results of this study warrant the testing of a 2-mg/kg dose of dapsone administered twice or thrice weekly to HIV-infected children. The monitoring of drug levels in plasma and dosage adjustment may be necessary for smaller children.
PMCID: PMC162691  PMID: 7625796
8.  Effect of inflammation on intraocular penetration of intravenous ofloxacin in albino rabbits. 
The effect of inflammation on the intraocular penetration of ofloxacin was studied in 20 albino rabbits (New Zealand White). Inflammation was induced in the left eye by inoculation of a suspension of 10(9) CFU of heat-killed Staphyloccus epidermidis per 0.1 ml of saline solution (0.9%) in the midvitreous cavity. The other eye was kept as a control. Twenty-four hours following inoculation, ofloxacin was administered in the marginal ear vein at a dose of 15 mg/kg over 20 min with an infusion pump. Animals were sacrificed at different times up to 24 h following drug administration. Ofloxacin levels were determined in aqueous humor, vitreous humor, and serum by a bioassay. Inflammation was scored on the basis of perilimbal and corneal reactions and vitreoretinal statuses. Inflammation had a relevant effect on intraocular penetration of ofloxacin, with levels in the ocular fluids of the inflamed eye markedly exceeding the ones of the control eye. In the uninflamed eye, the levels were rapidly decaying below assay sensitivity and were no longer detectable at approximately 5 h following drug administration while they were still detectable in both ocular fluids of the inflamed eye at 24 h. Ofloxacin levels in the ocular fluids of the inflamed eye were superior to the MIC for several of the bacteria which commonly cause endophthalmitis, including Staphylococcus epidermidis, Staphylococcus aureus, most members of the family Enterobacteriaceae, Haemophilus influenzae, and strains of Pseudomonas aeruginosa.
PMCID: PMC162578  PMID: 7726531
9.  Safety, activity, and pharmacokinetics of GLQ223 in patients with AIDS and AIDS-related complex. 
GLQ223 is a highly purified single-chain ribosome-inactivating protein with selective effects against a variety of cells, including macrophages infected with human immunodeficiency virus. We evaluated the safety, pharmacokinetics, and immunologic effects of multiple doses of GLQ223 in 22 patients with AIDS or AIDS-related complex; CD4+ T-cell counts were between 100 and 350/mm3. GLQ223 was administered intravenously at doses of 8, 16, 24, 36, and 50 micrograms/kg of body weight; the drug was administered by constant infusion over 3 h to achieve a concentration in serum of 50 ng/ml; this concentration is known to be associated with anti-HIV effects in vitro. All patients reported a flu-like syndrome characterized by muscle and joint aches and an increase in creatinine kinase levels; symptoms were controlled easily. For patients who received 36 and 50 micrograms/kg, target concentrations in serum were achieved and an increase in CD4+ and CD8+ T cells was sustained; this sustained increase persisted for at least 28 days after the last infusion. beta 2-Microglobulin levels increased during the infusions and then declined when the infusions ended. Repeat infusions of GLQ223 were safe and relatively well tolerated. The target concentration of GLQ223 in serum was achieved and sustained. Our results suggest that GLQ223 may have activity in treating patients with human immunodeficiency virus infection.
PMCID: PMC284438  PMID: 7910722
10.  Comparative study of bioavailabilities and pharmacokinetics of clindamycin in healthy volunteers and patients with AIDS. 
The absolute oral bioavailability and pharmacokinetics of clindamycin administered to 16 healthy volunteers and 16 patients with AIDS were compared. Clindamycin was given intravenously (i.v.) (Cleocin phosphate) at a dose of 600 mg as a 25-min infusion and orally (Cleocin hydrochloride) by use of a crossover design in both study groups. Plasma samples were analyzed by gas-liquid chromatography. Plasma drug clearance and volume of distribution at the steady state following the i.v. dose differed between study groups. The clearances were 0.27 +/- 0.06 liter/h/kg in healthy volunteers and 0.21 +/- 0.06 liter/h/kg in AIDS patients (P = 0.014; Mann-Whitney U test); the volumes of distribution at the steady state were 0.79 +/- 0.13 and 0.66 +/- 0.12 liter/kg in healthy volunteers and AIDS patients, respectively (P = 0.005). The elimination half-life did not differ between the two groups. The bioavailability of clindamycin capsules in AIDS patients was approximately 1.5 times that in healthy volunteers (0.53 +/- 0.14 versus 0.75 +/- 0.20; P = 0.002). Peak concentrations following the oral dose were higher in AIDS patients as well (7.7 +/- 2.5 versus 5.3 +/- 1.0 mg/liter; P = 0.0008). Three AIDS patients experienced severe diarrhea following the oral dose; four patients had mild diarrhea following the i.v. dose. No adverse effects were reported by the healthy volunteers. The pharmacokinetic parameters observed in this study for AIDS patients may be useful for the consideration of clindamycin dosage regimens in patients treated for toxoplasmic encephalitis. These findings suggest that the effect of AIDS on drug disposition deserves further investigation, particularly for orally administered drugs.
PMCID: PMC187917  PMID: 8517703
11.  Pharmacokinetics of GLQ223 in rats, monkeys, and patients with AIDS or AIDS-related complex. 
Antimicrobial Agents and Chemotherapy  1991;35(12):2531-2537.
The pharmacokinetics of GLQ223 administered as a single short intravenous infusion to rats, monkeys, and patients with AIDS or AIDS-related complex (ARC) are presented. GLQ223 was given at a dose of 3,500 micrograms/kg of body weight to five Sprague-Dawley rats; a dose of 300 micrograms/kg was given to three cynomolgus monkeys; and doses of 1, 8, 16, 24, and 36 micrograms/kg were given to 10 patients with AIDS and 8 patients with ARC in an escalating dose design. Plasma clearance was 0.85 +/- 0.24 liter/h/kg in rats, 0.16 +/- 0.08 liter/h/kg in monkeys, and 0.13 +/- 0.07 liter/h/kg in patients with AIDS or ARC. The volume of distribution at steady state was 0.42 +/- 0.12, 0.21 +/- 0.20, and 0.18 +/- 0.50 liter/kg in rats, monkeys, and patients, respectively. The elimination half-life was 1.3 +/- 0.4, 3.7 +/- 1.5, and 3.2 +/- 1.0 h in rats, monkeys, and patients, respectively. The disposition of GLQ223 was not dose dependent within the dose range tested in patients with AIDS or ARC. Interspecies pharmacokinetic scaling resulted in a good linear correlation for plasma clearance and the volume of distribution at steady state plotted versus species body weight on a log-log scale, indicating the predictability of elimination and distribution of GLQ223 among species. Allometric equations derived may be useful for the prediction of doses and dosage regimens to be used in animal models.
PMCID: PMC245426  PMID: 1810186
12.  Overexpression of calsequestrin in L6 myoblasts: formation of endoplasmic reticulum subdomains and their evolution into discrete vacuoles where aggregates of the protein are specifically accumulated. 
Molecular Biology of the Cell  1997;8(9):1789-1803.
Calsequestrin (CSQ), the major low-affinity Ca(2+)-binding glycoprotein of striated muscle fibers, is concentrated to yield aggregates that occupy the lumen of the terminal cisternae of the sarcoplasmic reticulum (SR). When infected or transfected into L6 myoblast, the protein is also concentrated, however, in dense vacuoles apparently separate from the endoplasmic reticulum (ER). CSQ-rich cells appear otherwise normal; in particular, neither other proteins involved in Ca2+ homeostasis nor ER chaperones are increased. The CSQ dense vacuoles are shown herein to be specialized ER subdomains as demonstrated by 1) the endoglycosidase H sensitivity of their CSQ and 2) two markers, calreticulin and calnexin (but not others, protein disulfide isomerase and BiP), intermixed with the vacuole content. Their formation is shown to start with the aggregation of CSQ at discrete sites of the ER lumen. When cells were transfected with both CSQ and calreticulin, only the first gave rise to vacuoles; the second remained diffusely distributed within the ER lumen. The possibility that CSQ aggregation is an artifact of overexpression appears unlikely because 1) within dense vacuoles CSQ molecules are not disulfide cross-linked, 2) their turnover is relatively slow (t = 12 h), and 3) segregated CSQ is bound to large amounts of Ca2+. Transfection of a tagged CSQ into cells already overexpressing the protein revealed the continuous import of the newly synthesized protein into preassembled vacuoles. The tendency to aggregation appears, therefore, as a property contributing to the segregation of CSQ within the ER lumen and to its accumulation within specialized subdomains. The study of L6 cells expressing CSQ-rich vacuoles might thus ultimately help to unravel mechanisms by which the complexity of the sarcoplasmic reticulum is established in muscle fibers.
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PMCID: PMC305737  PMID: 9307974

Results 1-12 (12)