Nonradioactive Quantification of Low Concentrations of Hemoglobin a by HPLC for Midtrimester Prenatal Diagnosis of β-Thalassemia

The usual methods for prenatal diagnosis of beta-thalassemia and other hemoglobinopathies by assay of fetal blood erythrocytes are either complex (analysis of globin chains synthesis by carboxymethylcellulose chromatography) or only semiquantitative [isoelectric focusing of hemoglobin (Hb)]. To further simplify the diagnostic procedure and to obtain quantitative data, we measured the small concentrations of Hb A in fetal erythrocytes by using a high-pressure liquid chromatography (HPLC) instrument (DIAMAT-TM; Bio-Rad) equipped with the new column proposed for measuring Hb A2. We analyzed 212 uncontaminated fetal blood samples obtained by cordocentesis between the 18th and 22nd weeks of pregnancy, using the HPLC procedure, and compared the results with those obtained by the above-named methods. The Hb A values obtained ranged between 0% and 8.5%; they were less than or equal to 1.8% in 44 fetuses affected by homozygous beta-thalassemia and greater than 2.5% in 168 unaffected fetuses. The method was simple, rapid, and reproducible (CV 3.2%) and there was good correlation between Hb A concentrations determined by HPLC and the beta/gamma ratio determined by carboxymethylcellulose chromatography (r = 0.7687; P less than 0.0001). No false-negative or false-positive results were observed, and there was no overlap of values between affected and unaffected fetuses.

Hyperprolactinaemia and prolactin binding in benign intracranial tumours

BACKGROUND

Meningiomas have been found to have receptors for several hormones, such as oestrogen, progesterone, somatostatin, dopamine and recently also for prolactin.

METHODS

To investigate any possible role of prolactin in the growth of those tumours we detected the presence of prolactin-receptors (PRL-R) in 22 meningiomas and we correlated these data with PRL serum levels in patients before surgery. We also studied 13 patients with schwannomas and 7 with other cerebral tumours (4 glioblastomas, 2 ependymomas and 1 astrocytoma).

RESULTS

Increased prolactin binding was present in 10 (45.4 percent;) meningiomas, 9 (69.2 percent;) schwannomas and in the patient with astrocytoma. The presence of high PRL levels was present in 6 (27.2 percent;) patients with meningiomas, 8 (61.5 percent;) with schwannomas and in 3 (42.8 percent;) with other tumours. No direct correlation was present between serum PRL levels and PRL binding in all groups.

CONCLUSIONS

In conclusion we confirmed the presence of PRL receptors in patients with meningiomas and we have also shown the presence of PRL receptors also in schwannomas. Moreover increased serum PRL were shown in some patients with different tumours of nervous tissue before surgery. Our data could suggest that PRL might have a role in the growth of meningiomas and schwannomas.

Comparison of pediatric and adult cerebral arteriovenous malformations

The authors report 19 consecutive children with cerebral arteriovenous malformations over the period 1978-1992. These patients are compared with a series of 120 consecutive adult patients with the same pathology, managed during the same period. The main clinical and angiographic features, as well as the treatment modalities and outcome are reviewed and compared. Children seem to harbour smaller and simpler lesions than adults. Furthermore, despite a more severe clinical presentation, children appears to fare better than adults. The possibility of evolution of brain arteriovenous malformations is discussed.

Aneurysms of the vertebro-basilar junction area: preliminary experience in endovascular and surgical management

Aneurysms of the vertebro-basilar junction area have been considered the most difficult to be surgically treated because of their deep location, the proximity of the brain stem and the cranial nerves. However, at present, new endovascular techniques and new transbasal surgical approaches offer valuable management strategies. This paper concerns six consecutive patients whom we managed either endovascularly or surgically during a period of eighteen months. Direct surgical treatment was offered to two young patients with relatively small aneurysms in good neurological condition, whereas the other four patients initially underwent an endovascular attempt at aneurysm obliteration using the Guglielmi detachable coil system. Unfortunately, interventional neuroradiology failed in three cases, and surgery had to be re-considered. Accordingly, a total of five patients underwent surgical clipping through the combination of a transmastoid retrolabyrinthine approach with the suboccipital lateral approach. This combination of approaches provided a good control of both vertebral arteries and basilar artery, and allowed the aneurysm to be correctly clipped in all cases. Good long-term results were achieved in all cases but one. Based on this preliminary experience, we would stress the importance of multidisciplinary approach with a treatment calibrated for each single case. Furthermore, if surgery is to be performed, the combination of transmastoid-retrolabyrinthine and suboccipital lateral approaches provides a wide exposure of the whole vertebro-basilar junction area and allows good access to the lesion.

Intraoperative monitoring of cerebral blood flow during ventricular shunting in hydrocephalic pediatric patients

Several studies have demonstrated lowered cerebral blood flow (CBF) in patients with hydrocephalus and symptoms of raised intracranial pressure. Ventricular shunting in such cases permits a sudden increase in CBF. The pathophysiology of functional brain deficit secondary to hydrocephalus is little understood. Improvement of the patient's clinical status after drainage of CSF suggests that cerebral dysfunction is not necessarily due to permanent brain damage. In fact, it improves rapidly after ventricular taps. In view of this it would be helpful to monitor cerebral perfusion. The transcranial Doppler (TCD) ultrasonography technique allows real-time monitoring of the intracranial circulation and makes it possible to evaluate the physiopathological correlation between ventricular dilatation and CBF. Continuous monitoring of the middle cerebral artery (MCA) by TCD was performed in three hydrocephalic children (2 months, 14 months, and 8 years old) during a ventricular-peritoneal shunt operative procedure. A TC-2000S device provided by an IMP-F fixed probe was utilized. In all patients, when the lateral ventricle was shunted and the CSF could flow away, a clear and sudden increase of flow velocity above 30% was detected. The pulsatility index (PI) was also pathologically increased in all patients. A gradual normalization of this index was revealed after the shunting procedure. Our experience has to be considered preliminary, but nonetheless, it suggests a clear correlation between hydrocephalic disease and concomitant CBF alterations.(ABSTRACT TRUNCATED AT 250 WORDS)

Peritumoral edema in meningiomas: microsurgical observations of different brain tumor interfaces related to computed tomography

Although generally benign tumors, meningiomas may be associated with extensive peritumoral brain edema as seen on computed tomographic scans. Fifty-two patients with intracranial meningiomas were studied, and the hypodense areas on computed tomographic scans were related to the intraoperative microsurgical findings and to the sizes of the tumors. We have identified three kinds of tumor-brain interfaces characterized by different difficulties in microsurgical dissection: smooth type, transitional type, and invasive type. These different microsurgical interfaces seem to correlate very precisely with computed tomographic images of halo-like and finger-like hypodense areas, allowing prediction of the microsurgical effort to be made in the surgery of meningiomas. The size of the tumor seems to be important in our subjects in determining the amount of edema produced. Indeed, a positive correlation (P < 0.001) was found between the sizes of the tumors and the extent of peritumoral hypodensity. A positive correlation (P < 0.002) also has been found between grade of edema and cortical penetration. Cerebral cortex disruption was systematically observed by us in invasive-type meningiomas and in 3 of 21 cases (14.3%) in transitional-type meningiomas. No penetration was observed in smooth-type meningiomas.

[The Mallampati's scale: a study of reliability in clinical practice]

The need to predict the rank of difficulty of tracheal intubation is of paramount importance in anaesthesia as has been well documented in numerous studies. We assessed the use of the Mallampati scale as possible predictive indicator of difficult tracheal intubation in a study conducted on 700 patients. The rank of difficulty determined during the pre-anaesthesiological examination by the Mallampati scale, was compared to the Cormack scale as assessed by the laryngeal direct examination at the beginning of anaesthesia. The correlation between the two first ranks of both scales was highly significant. The evaluation by the scale of Mallampati showed a good sensibility and a low specificity with incorrect overestimation only for the difficult intubation. In our study orotracheal intubation was rated difficult in 10.4% of the patients by the Mallampati scale and in 11% of the patients score by the Cormack scale. The chin to jugulum distance, also studied as a possible predictive parameter, did not correlate with the Cormack scale.

Nonradioactive quantification of low concentrations of hemoglobin A by HPLC for midtrimester prenatal diagnosis of beta-thalassemia

The usual methods for prenatal diagnosis of beta-thalassemia and other hemoglobinopathies by assay of fetal blood erythrocytes are either complex (analysis of globin chains synthesis by carboxymethylcellulose chromatography) or only semiquantitative [isoelectric focusing of hemoglobin (Hb)]. To further simplify the diagnostic procedure and to obtain quantitative data, we measured the small concentrations of Hb A in fetal erythrocytes by using a high-pressure liquid chromatography (HPLC) instrument (DIAMAT-TM; Bio-Rad) equipped with the new column proposed for measuring Hb A2. We analyzed 212 uncontaminated fetal blood samples obtained by cordocentesis between the 18th and 22nd weeks of pregnancy, using the HPLC procedure, and compared the results with those obtained by the above-named methods. The Hb A values obtained ranged between 0% and 8.5%; they were less than or equal to 1.8% in 44 fetuses affected by homozygous beta-thalassemia and greater than 2.5% in 168 unaffected fetuses. The method was simple, rapid, and reproducible (CV 3.2%) and there was good correlation between Hb A concentrations determined by HPLC and the beta/gamma ratio determined by carboxymethylcellulose chromatography (r = 0.7687; P less than 0.0001). No false-negative or false-positive results were observed, and there was no overlap of values between affected and unaffected fetuses.

[Frequency of microalbuminuria in children]

Urinary samples overnight collected from 550 pediatric patients with normal urine analysis and normal serum levels of creatinine, urea and glucose were tested for the presence of microalbuminuria by a latex test. Only 3 cases (0.6%) were positive even with RIA method; the difference with the percentage observed in adults (4.5%) is highly significant.

[Frequency of microalbuminuria in an adult population]

Urinary samples overnight collected from the thousand normotensive adults with normal urinalysis and normal serum levels of creatinine, urea and glucose were tested for the presence of microalbuminuria by latex test Sclavo. Fourty-five cases were positive: the values of microalbuminuria in 21 of these cases tested with RIA method exceeded 26 mg/l; one hundred twenty-six latex-negative cases evidenced lower RIA values. The high sensitivity of the test and its clinical significance suggest the need of an automatic procedure for detecting microalbuminuria in Albustix-negative urine samples.

Generation of new mouse sarcoma viruses in cell culture

Endogenous nontumor-producing type C viruses from C3H mice were used to generate rapid, solid tumor-inducing variants in cell culture. The new mouse sarcoma viruses induce undifferentiated sarcomas with a short latency period upon inoculation into newborn NIH Swiss mice. Transforming viruses appear only transiently, at a time when the virus-infected cells show morphologic alterations; both before and after this time, transforming viruses cannot be detected. These results show that variants of endogenous type C virus which contain transforming genes (oncogenes) can arise during spread of the endogenous virus in fibroblast lines in vitro as well as in susceptible tissues in vivo.