Designing effective anticancer-radiopeptides. A Molecular Dynamics study of their interaction with model tumor and healthy cell membranes

One of the greatest merit of the use of radiopeptides in oncology is their selectivity which, however, brings about the drawback that each radiopeptide is specific for a given tumor type. To overcome this problem the direction currently taken in drug design is that of radiolabelling peptide hormones (or their analogues), relying on their intrinsic ability to bind to specific receptors in precise areas of the human body, at the cost, however, of a poor selectivity against healthy cells. We present here an extensive Molecular Dynamics study of a promising alternative inspired by the mechanism through which antimicrobial peptides interact with the negatively charged bacterial membranes. Appropriately modifying the human antimicrobial peptide, LL-37, we designed a functionalized radionuclide carrier capable of binding more strongly to the negatively charged (model) tumor membranes than to the neutral healthy ones. The mechanism behind this behaviour relies on the fact that at the slight acidic pH surrounding tumor tissues the histidines belonging to the peptide get protonated thus making it positively charged. We have investigated by an extended numerical study the way in which this artificial peptide interacts with models of tumor and healthy cell membranes, proving by Potential Mean Force calculations that the affinity of the peptide to model tumor membranes is significantly larger than to healthy ones. These features (high affinity and generic tumor selectivity) recommend antimicrobial derived customized carriers as promising theranostic constructs in cancer diagnostic and therapy.

Comparison of diagnostic methods to detect piroplasms in asymptomatic cattle

This study was carried out to compare different diagnostic techniques to reveal the presence of piroplasms in asymptomatic cattle kept at pasture. Nineteen blood samples were collected from animals of two different areas of Emilia Romagna Region of Italy and processed for microscopic observation, PCR, serological test (IFAT) for Babesia bovis and Babesia bigemina antibodies and in vitro cultivation. The cultures were performed on both bovine and ovine erythrocytes. Seventeen blood smears (89%) were positive for piroplasms, while PCR was positive on 18 samples (95%). DNA sequencing of 18S rRNA identified the piroplasms as Theileria spp. In vitro cultures were successful for 6 samples (32%) cultured on bovine blood and subsequent identified these as Babesia major by PCR. On IFAT analyses of 16 samples, 36.8% resulted positive for B. bovis and 31.6% positive for B. bigemina. These results show, in the same animals, the co-infection with Babesia spp. and Theileria spp.; the detection of B. major was possible only using the in vitro cultures.

The Chiari II malformation: a surgical series

Thirty patients between the ages of 7 months and 24 years were treated surgically for symptomatic Chiari II malformation at the Arkansas Children's Hospital. All patients underwent at least bony decompression of the malformation. Assessments of the patients' conditions were made at 6 weeks and 1 year after surgery, and complications of surgery were noted. For a majority of the patients, the presenting symptoms were resolved following treatment (74% at 6 weeks and 80% at 1 year). Partial resolution occurred in several of the patients (17% at 6 weeks and 14% at 1 year). A small number remained the same at 6 weeks (6%) and at 1 year (3%), while 1 patient was worse after surgery. Ten of the patients with complete resolution in the short term required repeat surgery an average of 49 months after their original operation, after which they again attained complete resolution of their symptoms. Scales for clinical, radiographic and operative grading of the patients' conditions as mild, moderate or severe were devised, and these were employed to characterize the condition of each patient. Patients in each grading category had good results, with rates of complete symptomatic resolution ranging from 67 to 100%. Severity in each category was found to be well correlated with eventual recurrence of symptoms and need for reoperation.

Antenatal sonographic diagnosis of clubfoot: a six-year experience

In the period 1988 through 1993, 6351 pregnant women were referred to the Department of Obstetrics and Gynaecology, University "La Sapienza", Roma, for suspected fetal anomalies or maternofetal problems. All underwent serial transabdominal and/or transvaginal ultrasound scanning, which revealed a total of 235 fetuses with hydrocephalus, cardiac, or musculoskeletal malformations. Forty-one clubfeet were detected in 27 pregnancies in the early part of the second trimester of pregnancy. Of these, 14 feet in eight patients were isolated, and were classified as idiopathic. A clubfoot was associated with neural tube defects in six patients, with anomalies of the urinary and/or digestive system in a further six, with a cystic hygroma in two, and with other musculoskeletal abnormalities in the other six patients. Amniocentesis revealed an abnormal karyotype in six fetuses (22.2%). In only two cases was oligohydramnios present. In both these patients, a fetal urinary tract malformation was present Polyhydramnios was found in 18 cases, and a normal amount of amniotic fluid was found in the remaining seven cases. Polyhydramnios was present in six of the eight idiopathic clubfoot fetuses. Clubfoot is associated with musculoskeletal and visceral anomalies in a high proportion of cases. The association of clubfoot with polyhydramnios in a high proportion of cases does not support the hypothesis of intrauterine moulding as an etiological factor in its development. Ultrasonographical prenatal detection of a clubfoot should prompt amniocentesis, as the condition is associated with an abnormal karyotype in a significant proportion of cases.