1p36 deletion syndrome: Review and mapping with further characterization of the phenotype,a new cohort of 86 patients

Chromosome 1p36 deletion syndrome (1p36DS) is one of the most common terminal deletion syndromes (incidence between 1/5000 and 1/10,000 live births in the American population), due to a heterozygous deletion of part of the short arm of chromosome 1. The 1p36DS is characterized by typical craniofacial features, developmental delay/intellectual disability, hypotonia, epilepsy, cardiomyopathy/congenital heart defect, brain abnormalities, hearing loss, eyes/vision problem, and short stature. The aim of our study was to (1) evaluate the incidence of the 1p36DS in the French population compared to 22q11.2 deletion syndrome and trisomy 21; (2) review the postnatal phenotype related to microarray data, compared to previously publish prenatal data. Thanks to a collaboration with the ACLF (Association des Cytogénéticiens de Langue Française), we have collected data of 86 patients constituting, to the best of our knowledge, the second-largest cohort of 1p36DS patients in the literature. We estimated an average of at least 10 cases per year in France. 1p36DS seems to be much less frequent than 22q11.2 deletion syndrome and trisomy 21. Patients presented mainly dysmorphism, microcephaly, developmental delay/intellectual disability, hypotonia, epilepsy, brain malformations, behavioral disorders, cardiomyopathy, or cardiovascular malformations and, pre and/or postnatal growth retardation. Cardiac abnormalities, brain malformations, and epilepsy were more frequent in distal deletions, whereas microcephaly was more common in proximal deletions. Mapping and genotype–phenotype correlation allowed us to identify four critical regions responsible for intellectual disability. This study highlights some phenotypic variability, according to the deletion position, and helps to refine the phenotype of 1p36DS, allowing improved management and follow-up of patients.     

Post graft development of short children treated with growth hormone before kidney graft

Sixteen prepubertal patients with chronic renal failure (CRF) were given daily recombinant human growth hormone (rhGH) treatment (1.2 IU/kg per week) for 2.6±1.6 years until kidney transplant. Therapy was then discontinued and the patients followed for a further 3.5±1.4 years. During treatment, mean height increased from –3.0±0.9 standard deviation score (SDS) to –1.9±1.4 SDS (P<0.001) at the time of transplantation, corresponding to a mean height gain of +1.2±0.9 SDS. After discontinuation of rhGH therapy, prepubertal children continued a partial catch-up growth with a height gain of +0.5±0.8 SDS for the follow-up period. Conversely, negative changes of height were observed in pubertal transplanted children: –0.5±0.4 SDS in patients grafted at early stages of puberty (P2–P3) and –0.15±0.9 SDS in patients grafted at late stages of puberty (P4–P5). These data confirmed the benefit of rhGH therapy in CRF patients. Nevertheless, only early initiation of rhGH treatment led some of these patients to their target height at transplantation, thus preserving their potential growth. Reinitiation of rhGH therapy after transplantation should be considered in order to complete catch-up growth to target height in prepubertal children. Received: 23 July 1998 / Revised: 8 December 1998 / Accepted: 13 December 1998     

Vinflunine (20′,20′-difluoro- 3′,4′-dihydrovinorelbine), a novel Vinca alkaloid, which participates in P-glycoprotein (Pgp)-mediated multidrug resistance in vivo and in vitro

Vinflunine (VFL) is a novel derivative of vinorelbine (NVB, Navelbine®), which has shown markedly superior antitumor activity to NVB, in various experimental animal models. To establish whether this new Vinca alkaloid participates in P-glycoprotein (Pgp)-mediated multidrug resistance (MDR), VFL-resistant murine P388 cells (P388/VFL) were established in vivo and used in conjunction with the well established MDR P388/ADR subline, to define the in vivo resistance profile for VFL. P388/VFL cells proved cross-resistant to drugs implicated in MDR (other Vinca alkaloids, doxorubicin, etoposide), but not to campothecin or cisplatin and showed an increased expression of Pgp, without any detectable alterations in topoisomerase II or in glutathione metabolism. The P388/ADR cells proved cross-resistant to VFL both in vivo and in vitro, and this VFL resistance was efficiently modulated by verapamil in vitro. Cellular transport experiments with tritiated-VFL revealed differential uptake by P388 sensitive and P388/ADR resistant cells, comparable with data obtained using tritiated-NVB. In various in vitro models of human MDR tumor cells, whilst full sensitivity was retained in cells expressing alternative non-Pgp-mediated MDR mechanisms, cross resistance was identified in Pgp-overexpressing cells. Differences were, however, noted in terms of the drug resistance profiles relative to the other Vincas, with tumor cell lines proving generally least cross-resistant to VFL. Overall, these results suggest that VFL, like other Vinca alkaloids, participates in Pgp-mediated MDR, with tumor cells selected for resistance to VFL overexpressing Pgp, yet MDR tumor cell lines proved generally less cross resistant to VFL relative to the other Vinca alkaloids.     

Prevalence and Clinical Significance of Her-2/neu, p53 and Rb Expression in Primary Superficial Bladder Cancer

Purpose

The usefulness of the expression of HER2/neu oncoprotein and of p53 and Rb suppressor gene product as predictors of tumor recurrence was evaluated by using a bank of prospectively collected primary papillary bladder tumors treated initially only by transurethral resection.

Materials and Methods

The expression of HER-2/neu oncoprotein and of p53 and Rb suppressor genes was evaluated by immunohistochemistry in 256, 265 and 74 specimens of primary Ta/T1 superficial bladder tumors obtained from patients enrolled in a prospective study from 1990 to 1992. Survival analysis was used to evaluate the association between time to first recurrence and expression of each marker, the follow-up period extending to March 1994. Immunostaining for p53 and HER-2/neu was performed on paraffin-embedded tissue and, for Rb, on frozen tissue only.

Results

Her-2/neu was expressed in 21 (8.2 percent) cases and p53 in 39 cases (14.7 percent); Rb expression was altered in 12 (16.2 percent). In this study, p53 expression was only related to earlier recurrence in a univariate analysis. Multivariate analysis, however, failed to recognize p53 expression as an independent predictor of recurrence.

Conclusions

Our study demonstrate the low prevalence of HER2/neu, p53 and altered Rb expression in superficial TCC at initial resection. Only p53 expression was significantly associated with an earlier first tumor recurrence, but this association was not independent of other prognostic factors.     

Sonographic evaluation of renal masses: Correlations with angiography

The value of sonography in the diagnosis of renal masses in a series of 119 consecutive histologically confirmed cases is presented. Sonography correctly identified 92% of the cystic and 90% of the solid renal masses. Causes of incorrect diagnoses included lesions smaller than 2 cm, masses in the left upper pole, diffusely infiltrating urothelial tumors, echogenic fatty lesions (early in our experience), and acute abscesses and hematomas. Angiography in the same series of cases correctly diagnosed 80% of the cystic and 88% of the solid renal masses. Avascular lesions were the main cause for equivocal or incorrect angiographic diagnoses. We conclude that sonography is more definitive than angiography in the diagnosis of avascular masses, while angiography excels when the lesion is vascular or small. Combining the sonographic and angiographic findings allowed accurate diagnosis in over 99% of the cases.     

Epidemiological aids to clinical decision making in primary open angle glaucoma

We have described the epidemiological analysis of one aspect of the King's College Hospital computerised data base; namely initial intraocular pressure as an indicator of visual field loss. The methods involved the use of the four-fold table to determine sensitivity and specificity at different pressure levels. From these results (1) the changes in the pre and post test probability of field loss are calculated and (2) a sensitivity/specificity trade off curve or decision curve is constructed. In this way the optimal cut-off level or operating point for a population of specific type and composition can be determined. The factors concerned in decision making are always complex but such an approach allows a rational and quantifiable alternative to reliance on clinical impression and intuition. The results have significance in relation to decisions on the management of patients and on population screening programmes for glaucoma.     

Development and characterization of naproxen-chitosan solid systems with improved drug dissolution properties.

The solubilizing and amorphizing properties toward naproxen (a poorly water-soluble antiinflammatory drug) of chitosan, an emerging pharmaceutical biopolymer, have been investigated. Solid binary systems at different drug/polymer ratios have been prepared according to different techniques (mixing, cogrinding, kneading, coevaporation) using chitosan at low (CS-L(w)) and medium (CS-M(w)) molecular weight, and tested for dissolution properties. Drug-carrier interactions were investigated in both the liquid and solid state, by phase solubility analysis, differential scanning calorimetry, X-ray powder diffractometry, FT-IR spectroscopy, and scanning electron microscopy. Drug dissolution parameters improved with increasing the polymer amount in the mixture, reaching the highest values at the 1:9 (w/w) drug/polymer ratio, and CS-L(w) was more efficacious than CS-M(w). Cogrinding was the most effective technique, showing the strongest amorphizing effect toward the drug and enabling an increase of more than ten times its relative dissolution rate. Coground mixtures at 3:7 (w/w) drug/polymer ratio were able to give directly compressed tablets which maintained unchanged the improved drug dissolution properties. Enhancer dissolution properties combined with its direct compression feasibility and antiulcerogenic action make CS-L(w) an optimal carrier for developing fast-release oral solid dosage forms of naproxen.