Circular dichroism detection in high-performance liquid chromatography: Evaluation of the anisotropy factor

The application of a circular dichroism (c.d.) detection system in HPLC using a chiral stationary phase is presented. The simultaneous measurement of the absorbance and c.d. signal allows the evaluation of the anisotropy factor (g = Δ/) and thus the determination of the enantiomeric excess (e.e.) of the eluates. When this detection system is used in preparative chiral chromatography the collection of the enantiomeric fractions can be readily optimized.     

Chromatic pattern-reversal electroretinograms (ChPERGs) are spared in multiple system atrophy compared with Parkinson’s disease

Abstract Idiopathic Parkinson’s disease (IPD) patients have abnormal visual evoked potentials (VEPs) and pattern electroretinograms (PERGs), attributed to dopaminergic transmission deficiency in visual pathway, probably the retina. VEP abnormalities are not reported in multiple system atrophy (MSA). The aim of this study was to investigate and compare chromatic (Ch) red-green (R-G) and blue-yellow (B-Y), and luminance yellow-black (Y-Bk) PERGs in patients with MSA and IPD. We investigated 6 MSA patients (mean age: 62±7.4 years) not undergoing any pharmacological treatment, as well as 12 early IPD patients (mean age: 60.1±8.3 years) and 12 age-matched normal observers. ChPERGs were recorded monocularly in response to full-field equiluminant R-G, B-Y and Y-Bk horizontal gratings. In MSA only responses to R-G stimuli showed minimal insignificant changes (slight but not significant amplitude reduction without any significant latency delay); no significant abnormality was detected for B-Y and luminance Y-Bk stimuli. By contrast, in IPD all responses were reduced in amplitude and delayed in latency, above all for B-Y stimuli. Present data indicate that both chromatic and achromatic PERGs are virtually unaffected in MSA, whereas in early IPD they are clearly impaired, suggesting different pathogenic retinal mechanisms and a useful simple tool for distinguishing MSA from IPD.     

Problems related to resuscitation in studies with contrast media]

This study has the purpose of describing indications and legal implications related to the intravascular use of contrast media (ICM) in order to provide useful guidelines to the intensivist, often involved in the treatment of adverse reactions. The structure of modern contrast media (CM), is a benzenic ring carrying steadily three iodine ions. Adverse reactions due to the use of ICM, are local or systemic ranging from skin rashes or flushes (urticaria et al.), to cardiovascular, respiratory and neurologic symptoms. The prevention of these reactions is mandatory in patients reporting a history of allergy or atopia disease. From a legal point of view, the contraindication to procedures involving i.v. use of CM are not clearly pointed out therefore several concerns have been expressed. The intensivist is not required to physically attend the procedure, in agreement with the circular #64 edited in 1979; on the other hand his prompt intervention should be granted if necessary. Furthermore every therapeutic supply suitable for any resuscitational intervention should be available in the area where the test is performed. In conclusion we would like to stress the financial and ethic implications related to the choice of ICM (ionic versus non-ionic). The use of non-ionic CM offers several advantages: among them the better tolerance for the patient and the lower incidence of adverse reactions. However non-ionic CM have a cost ten-fold higher and both groups of drugs have same incidence of fatal reactions, therefore the use of non-ionic ICM is recommended for high risk patients.     

A leg ulcer as manifestation of metastatic squamous cell vaginal carcinoma

Cutaneous metastasis of vaginal carcinoma is extremely rare. So far, the total number of reported skin metastasis of vaginal carcinoma is only one. We present another case with an unusual manifestation of vagina carcinoma metastasis: skin metastasis presenting as a leg ulcer on the lower leg.