Expression and Down-Regulation by Retinoic Acid of IGF Binding Protein-2 and -4 in Medium from Human Neuroblastoma Cells

Insulin-like growth factors (IGFs) regulate the autocrine/paracrine growth of neuroblastomas. The IGFs bind to specific binding proteins (IGFBPs) which modulate their biological activity. We investigated, by Western ligand blotting (WLB), the presence of IGFBPs and their possible modulation by retinoic acid (RA), IGF-I, IGF-II and truncated Des(1-3)IGF-l in conditioned medium (CM) of the human neuroblastoma SK-N-BE(2) cell line. We demonstrated the presence of two IGFBPs, with MW 37 kDa and 25 kDa. Following immunoprecipitation, they turned out to be IGFBP-2 and -4, respectively. The RA-induced differentiation in SK-N-BE(2) cells was accompanied by a marked reduction of the intensity of both IGFBP bands after 48 h (32% and 24% of control, respectively) and 72 h (2% and 0% of control, respectively) incubation. The addition of exogenous IGFs, which did not induce cell differentiation, did not change the IGFBP pattern significantly, except for the truncated form of IGF-I, which induced a marked decrease in both the 37 kDa and 25kDa bands after 72 h incubation (45% and 18% of control, respectively). These findings suggest that IGFBPs have a role in RA-induced differentiation in human neuroblastoma cells.     

Keeping track of a conversation: Impairments in Alzheimer's disease

Earlier research suggests that AD patients tend to be particularly impaired in the central executive component of working memory, leading to problems in coordinating information from different sources. This suggests that they may be particularly handicapped in keeping track of conversations involving several people. This was studied in 19 AD and 19 matched control subjects. The patients were screened to minimize problems of face recognition and language comprehension and were then shown videotapes of conversations involving from two to five characters. After each tape, a statement made by one of the characters was presented and the subject required to point to the person who had made that statement. Performance was at ceiling for normals, except when the speakers had changed location, when some errors occured. AD patients showed a clear tendency for performance to deteriorate as number of speakers increased, and to show higher error rates when participants changed location. Implications are discussed for AD patients attempting to cope with everyday social situations.     

Intestinal metabolism of tyramine by both forms of monoamine oxidase in the rat

The two forms of monoamine oxidase (MAO) in rat intestine and brain homogenates were found to have different K_m and V_max values towards tyramine. The K_m values for the A-form of the enzyme towards this substrate were around 120 μM in both cases, whereas the values for the B-form were about 240 μM. As a consequence, the ratio of activities (MAO-A: MAO-B) towards tyramine are dependent upon the substrate concentration. The MAO-A-selective inhibitors, toloxatone and cimoxatone, were found to be competitive inhibitors of the oxidation of tyramine by the A-form of this enzyme in the rat intestine, with K_i values of 3.4 μM and 3.7 nM respectively. The significance of these results in relation to the “cheese effect”, a pressor response to tyramine after monoamine oxidase inhibition, are discussed.     

Influence of GABA on anaphylactic histamine releasein vitro

In this preliminary report an unreported inhibitory action of GABA on anaphylactic reaction has been described. In a functional model (Schultz-Dale reaction) GABA has been demonstrated to inhibit the antigen-evoked contraction. This effect depends on a modulation of anaphylactic histamine release. The phenomenon is dose-dependent and requires a period of time to develop. Since GABAergic neurons are present in the preparation, it is possible to speculate that GABA receptors are involved in this inhibitory action. However, pharmacological analysis of the phenomenon has to be carried out, especially in view of the latency of GABA to develop its effect.     

A comparison of familial and sporadic migraine in a headache clinic population

We compared the clinical, psychological and pharmacological characteristics of patients with familial migraine and patients with sporadic migraine. Five hundred and thirty consecutive new patients attending our Headache Center over a two-year period were involved in the study. The patients were divided into two groups: A. Familial migraine (famM)--at least one first-degree relative affected; B. Sporadic migraine (spoM)--no first-degree relative affected. Four hundred and twenty-four patients (80%) fulfilled the criteria for famM and 106 (20%) for spoM. The patients with famM showed a significantly (p<0.01) earlier age at onset of the disease. No significant difference in all the remaining features examined was found. Our data suggest that famM and spoM represent a single disease entity.     

Thin section MR study of the basal ganglia in the differential diagnosis between striatonigral degeneration and Parkinson disease

PURPOSE: Signal abnormalities within the putamen in MRI have been related to tissue degeneration in the striatonigral variant of multiple system atrophy (MSA-P). While previous work demonstrated the high specificity of these MR findings, sensitivity rates were unsatisfactory. We evaluated the specificity and sensitivity of an acquisition protocol using thin section MRI to differentiate MSA-P from Parkinson disease (PD). METHOD: Axial 3-mm-thick conventional T2 and proton density spin echo images at the level of basal ganglia were acquired at 1.5 T in 24 patients with MSA-P and 27 patients with PD. RESULTS: We found an abnormal putaminal T2 hypointensity in 21 of 24 MSA-P patients (87.5% sensitivity) and a proton density hyperintensity in 20 of 24 MSA-P patients (83.3% sensitivity). Three among 27 PD patients had an abnormal putaminal T2 hypointensity (88.8% specificity) and there were no proton density abnormalities (100% specificity). CONCLUSION: Our thin section conventional spin echo protocol showed a substantial increase in MR sensitivity compared with previous reports. We believe that a better depiction of even mild signs of degeneration in the putamen may allow a more widespread use of this technique in the differential diagnosis of parkinsonisms.     

Controlled disassembling of self-assembling systems: toward artificial molecular-level devices and machines

Investigations on self-assembling/induced-disassembling systems have led to the design of molecular-level devices capable of performing a variety of functions. Some of the work carried out in this field is illustrated.     

Minimally invasive adrenalectomy for pheochromocytoma during pregnancy

Pheochromocytoma during pregnancy is a very rare condition; fewer than 200 cases have been reported in the literature. We present the case of a 24-year-old pregnant woman found to have a pheochromocytoma during investigation of abdominal pain. This is the second reported case of laparoscopic adrenalectomy for pheochromocytoma detected during pregnancy. After appropriate radiologic investigation and medical management, a laparoscopic left adrenalectomy was performed at the beginning of the second trimester. There were no complications, and she was delivered of a healthy baby at term. We review the management of pheochromocytoma in pregnant patients and discuss the role of laparoscopy.     

The ultrasonographic image of the infant hip affected by developmental dysplasia with a positive Ortolani's sign

Instability of the hip may be assessed by the Ortolani and Barlow tests, which are the keystone of clinical screening for developmental dysplasia of the hip (DDH). However, Ortolani's sign implies that there is strong evidence of a severe form of DDH with a completely dislocated, but still reducible, femoral head. Barlow's test addresses several different forms of "instability" of the hip that are quite difficult to describe and in 80% of cases disappear during growth. For this reason, Ortolani's sign in a baby should be considered an indication for emergency treatment to reduce and stabilise the hip while it is still reducible. The increasingly widespread use of US of the hip in newborns and infants has enabled clinicians to observe the hip from the first day of life and to establish both the static and dynamic relationships of the femoral head and acetabulum. The purpose of this paper is to describe the US pattern and relative classification of the hip affected by Ortolani's sign and examined by Graf's method, and to confirm through US that Ortolani's sign should be considered a totally reliable specific test for the identification of dislocation of the infant hip.