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Biomedical subjects

M Longo

Publications and source records attributed to M Longo.

At least 19 recordsLinked to original sources
PubMed1992

Cloning and characterization of genes for the PvuI restriction and modification system.

The genes encoding the endonuclease and the methylase of the PvuI restriction and modification system were cloned in E.coli and characterized. The genes were adjacent in tandem orientation spanning a distance of 2200 bases. The PvuI endonuclease was a single polypeptide with a calculated molecular weight of 27,950 daltons. The endonuclease was easily detectable when the gene was expressed from its endogenous promotor and present on a low copy plasmid, but expression was considerably enhanced when the endonuclease gene was placed under the control of a strong promoter on a high copy plasmid. The methylase did not completely protect plasmid DNA from R.PvuI digestion until the methylase gene was placed under lac promotor control in a multicopy plasmid. In the absence of the M.PvuI methylase, expression of the R.PvuI endonuclease from the lac promotor on a multicopy plasmid was not lethal to wild type E.coli, but was lethal in a temperature-sensitive ligase mutant at the non-permissive temperature. Moreover, induction of the R.PvuI endonuclease under lambda pL promotor control resulted in complete digestion of the E.coli chromosome by R.PvuI.

Base Sequence↗
PubMed1992

Renal needle biopsy of the transplant kidney: vascular and urologic complications.

The authors reviewed the complications of 114 needle biopsies performed in 103 transplant kidneys. The diagnostic and therapeutic approach has changed markedly as a result of the introduction of Doppler ultrasound and the possibility of selectively embolizing fistula tracts. Macroscopic haematuria was the most frequent complication (5%); in one case it appeared 1 week after biopsy and was complicated with obstructive anuria due to a pyeloureteric clot. The incidence of arteriovenous fistulae was fairly low (0.9%); a selective renal angiography was performed, confirming the vascular lesion and allowing its selective embolization. Perirenal blood collections were also rare and the amounts were small.

Adult↗
PubMed1992

[Thr role of histiocytes in the cytodiagnosis of endometrial adenocarcinoma].

The Authors point out the importance of histiocytes in Papanicolaou smears. Histiocytes are associated with endometrial carcinoma on tissue sections and may be seen on cervicovaginal smears as well. Smears obtained from 120 women, with clinical signs of endometrial diseases, were evaluated to determine the correlation between the presence of histiocytes in the cervicovaginal smears and endometrial adenocarcinoma. Histiocytes were quantified as minimal [less than 5 per high-power field (hpf)], moderate (5-10 hpf) or heavy (greater than 10/hpf). The histiocytes were found in smears from 80 women. Five adenocarcinomas, 9 hyperplasias were detected in 20 patients with moderate or heavy smears. The Authors conclude that the presence of histiocytes among postmenopausal women who have cervicovaginal smears should not be ignored. The data indicate that, in the absence of endometrial cells, histiocytes on cervicovaginal smears of postmenopausal women are associated with more elevated relative risk for endometrial carcinoma.

Adenocarcinoma↗
PubMed1992

[Association between inguinal endometriosis and polycystic ovary].

A case of inguinal endometriosis is described in a patient affected by PCOD. To the best of our knowledge, this is the first case of this type of association reported in the literature although cases in which endometriosis was related to high estrogen levels are well documented. We suggest that in the presence of high estrogen levels (absolute or relative hyperestrinism), the foci of endometriosis might not prove a rare condition if clinicians and pathologists lashed for it carefully.

Adult↗
PubMed1991

Arteriovenous fistula between descending aorta and hemiazygos vein.

The article describes a rare case of congenital A-V fistula between descending aorta and hemiazygos vein in a 9-year old girl. Differential diagnosis in these cases is difficult and only sonography and angiography can lead to a correct diagnosis. The recent literature of this subject is reviewed.

Angiography, Digital Subtraction↗
PubMed1991

Cluster-like headache and a median intracranial calcified lesion: case report.

A 69 year old man complaining of a cluster-like headache is reported. CT scan showed a median intracranial calcified lesion. Two main considerations are: 1) the importance of searching for an underlying structural lesion in patients with an "atypical" cluster headache; 2) the possible significance of a lesion localized close to the midline structures in the pathogenesis of cluster headache.

Aged↗
PubMed1990

Neonatal malignant solid tumors.

We reviewed the 8 malignant solid tumors in children less than 1 month of age observed at the Pediatric Surgical Department of Padua University from 1968 to 1985. These were 6 neuroblastomas, 1 Wilms' tumor and 1 angiosarcoma; 5/8 are alive without evidence of disease with a median follow-up of 8 years. The importance of combined therapeutic approach and conservative surgery are stressed. The sensitiveness of infants to both chemotherapy and radiotherapy are considered. Surgery remains the treatment of choice when a radical resection is possible.

Combined Modality Therapy↗
PubMed1990

Epidural spinal meningioma. Role of magnetic resonance in differential diagnosis.

A rare case of an extradurally growing spinal meningioma in an elderly woman is reported. Neuro-imaging, particularly magnetic resonance (MR), allowed to recognize the lesion, which, otherwise, could raise problems of differential diagnosis with a spinal metastasis. An emergency operation, required by a sudden neurological deterioration, was decisive in recovery of neurological deficits. In a review of the literature, extradurally growing spinal meningiomas appear to occur with a higher frequency than it is thought. Therefore, they are to be suspected when dealing with extradural spinal lesions.

Aged↗
PubMed1990

[Trans-sphenoidal spread of rhinopharyngeal neoplasms. Correlations between computerized tomography and magnetic resonance].

In 1957 Teoh observed, in an autopsic series of 31 patients with nasopharyngeal carcinoma, 3 cases of neoplastic spread through the marrow spaces of the base of the skull, without macroscopic bone alterations. In order to demonstrate in vivo this kind of neoplastic spread, CT and MR examinations of 35 patients with nasopharyngeal carcinoma were reviewed. In 3/26 cases the invasion of the marrow spaces of the clivus was demonstrated. In these cases CT showed only minimal alterations in spongiosa and cortices of the clivus, associated with intracranial soft-tissue tumoral components. MR imaging demonstrated, with great accuracy, the replacement of bone marrow in the clivus by neoplastic tissue of intermediate signal intensity on T1-weighted images. Tumor tissue was characterized by high signal intensity on T2-weighted images. The authors stress the greater utility of MR imaging in evaluating the permeative involvement of the base of the skull.

Adult↗
PubMed1989

Nocturnal complex partial seizures precipitated by REM sleep. A case report.

A 16-year-old patient presenting with complex partial seizures occurring in the transition from a REM period to wakefulness is described. His baseline EEG showed generalized and symmetrical slow spike and wave complexes, on a normal background activity, activated by NREM sleep. Polygraphic and videotape recordings, carried out for several nights, showed that after nearly each REM period, he would wake up briefly, presenting eye blinking followed by a burst of generalized hypersynchronous theta to start his seizures. These were characterized by moaning and autoaggressive behaviour, the ictal EEG showing generalized slow spike and wave complexes in the midst of several movement artifacts. At the end of each fit he fell back to REM sleep. Carbamazepine treatment completely resolved his symptoms, with full normalization of EEG activity.

Adolescent↗
PubMed1989

Bilateral cortical calcifications with benign clinical course: an unusual case of Sturge-Weber syndrome?

A case of a 13-year-old girl with bilateral cortical calcifications of the Sturge-Weber type at CT examination, without cutaneous lesions and ocular abnormalities is described. She had seizures appearing within the first year of life which never recurred since the age of two years. At the age of ten years she began to suffer from occasional migraine attacks. Her neurological examination and psychological testing did not show any significant abnormality. This case can be regarded as an unusual atypical form of Sturge-Weber syndrome, unless the existence of a new disorder is assumed.

Angiomatosis↗
PubMed1988

Perineural spread of nasopharyngeal carcinoma: radiological and CT demonstration.

Perineural spread is well known to be the most insidious form of tumour spread of a number of head and neck malignancies. However, perineural extension of nasopharyngeal carcinoma (NC) is a poorly recognized event. Four cases of perineural metastases from NC have been detected with pluridirectional tomography and CT. In 3 cases involvement of the Vidian nerve (nervus canalis pterygoidei) and pterygoid canal was observed. In a fourth patient, invasion of one pterygopalatine fossa and perineural spread along ipsilateral maxillary nerve with enlargement and erosion of the foramen rotundum was demonstrated. Radiological diagnosis of clinically unsuspected perineural tumour spread is important because it markedly influences treatment planning and prognosis of NC.

Carcinoma↗
PubMed1987

Age-related differences in lymphocyte adherence to myelinated tissue in multiple sclerosis.

Human peripheral blood lymphocytes were obtained from patients with MS and from healthy controls. Comparisons were made between the adherence of lymphocytes from donors of varying ages to myelin from donors of different age groups at the time of death. The adherence of control lymphocytes was maximum with lymphocytes from donors in their 30s. No obvious maximum for lymphocyte age was found for adherence of MS lymphocytes. However, MS adherence levels were significantly higher than control levels at most ages tested. Maximum adherence levels were observed for both MS and control cells with myelin from donors who were 20 to 45 years of age at the time of death. No significant difference between MS and control adherence to myelin from elderly donors was observed. Possible age-related changes in myelin and the relationship of maximum adherence to the peak age of onset of MS discussed.

Adolescent↗
PubMed1986

Serum 13-14-diOH-15-keto-prostaglandin F2 alpha and airway response to meclofenamate and metaproterenol in relation to the menstrual cycle.

In order to evaluate whether adverse reactions to a nonsteroidal antiinflammatory agent (NSAIA) were related to variations in prostaglandin levels during the menstrual cycle, we measured 13-14-diOH-15-keto-prostaglandin F2 alpha in serum and the effect on airways of a single dose of 100 mg oral meclofenamate and 1.5 mg inhaled metaproterenol during the early (follicular phase) and late (luteal phase) menstrual cycle. Among 24 women with premenstrual asthma (PMA), four women with regular asthma (REA), and four healthy women, the 13-14-diOH-15-keto-PGF2 alpha averaged 140.9 +/- 68.4 pg/0.1 ml during the follicular phase but only 14.4 +/- 2.2 pg/0.1 ml during the luteal phase (p less than 0.0001). Acute asthma reactions to the meclofenamate occurred during the follicular phase in six women with PMA but were never observed during the luteal phase (p = 0.016). These reactions occurred preferentially in patients on corticosteroids (p = 0.004). Conversely, one patient with PMA had 18% improvement in FEV1 with meclofenamate during the luteal phase. A placebo-controlled, double-blind evaluation of the healthy women and the women with REA revealed a trend toward improvement in FEV1 during the luteal phase (0.15 less than p less than 0.10) but no change during the follicular phase. The effect of metaproterenol did not vary with the menstrual cycle, and there was no interaction between the effects of meclofenamate and those of metaproterenol. It appears that meclofenamate causes adverse effects on pulmonary function in asthmatic women primarily during the follicular phase of the menstrual cycle. This effect is associated with corticosteroid treatment and may be related to monthly variation in serum 13-14-diOH-15-keto-PGF2 alpha.

Adult↗