Molecular cloning of Rab-related genes in the yeast Yarrowia lipolytica. Analysis of RYL1, an essential gene encoding a SEC4 homologue.

Small GTP-binding proteins of the Rab family are involved in the vesicular traffic inside eukaryotic cells. A gene library from the yeast Yarrowia lipolytica was screened with an oligonucleotide deduced from a highly conserved sequence in the Rab family. Four different genes were isolated. One of them, RYL1, was shown to be essential for cell viability. RYL1p displayed a high similarity with and tight phylogenetic relationships to SEC4p. When placed under the control of the GAL10 promoter, RYL1 was able to specifically relieve the thermosensitivity of a sec4-8 mutant of Saccharomyces cerevisiae. Therefore, it is proposed that RYL1 is a functional homologue of the S. cerevisiae SEC4 gene and is involved in the fusion of secretory vesicles with the plasma membrane in the general protein secretion pathway.

Possible relation between the U54 segment of the CTHV genome and the conserved gene block C rearranged in alpha and gamma herpesvirus genomes.

The genome of CTHV is an atypical member of the gamma-2 subgroup of herpesvirus genomes that contains two segments (instead of one) of DNA with low G+C content flanked by highly repetitious DNA with high G+C content. The segments freely undergo polarity inversion with respect to one another. We have found nucleotide sequences in one of these segments, the U54 segment, whose putative translational products show clear similarity to two ubiquitous herpesvirus gene products, a single-stranded DNA binding protein and a protein of the helicase superfamily. These sequences are located within 5 kilobase pairs of the ends of the segment, suggesting that U54 may be related to a genetically defined entity (gene block C; Davison and Taylor (1987) J. Gen Virol. 68, 36-48) issuing from a previous sequence comparison of the gamma-1 genome of Epstein-Barr virus and the alpha genome of varicella-zoster virus.

Clipping of the anterior communicating artery to eliminate the contralateral blood supply in supratentorial large AVM of the carotid system. A report of 22 cases.

Large supratentorial arteriovenous malformations (AVMs) of the carotid system are vascularized by the ipsilateral internal carotid artery (ICA) and often, in addition, by the contralateral ICA via the anterior communicating artery (ACoA). In these AVMs we have previously advocated (1981) multiple staged operations with the progressive reduction of the blood stream passing through the AVM. In twenty-two cases, starting in 1983, the reduction of the blood stream into the shunt has been performed as a first operation by placing a clip on the middle of the ACoA through a pterional approach on the opposite side of the AVM before radical open surgery. Results were excellent when considering the control angiogram and the measurement of the blood velocity in the ICA opposite to the AVM side. There were no neurological complications and no mortality.

[Unruptured intracranial saccular aneurysms less than 20 mm in diameter in adults. Radical surgery in 89 cases]. / Les anévrysmes artériels sacculaires intracrâniens non rompus de l'adulte d'un diamètre inférieur à 20 mm. Chirurgie radicale dans 89 cas.

Between 1972 and 1989, 131 unruptured intracranial saccular aneurysms were clipped in the Neurosurgical Department of La Pitié Hospital, Paris. Only 89 of these are considered here, the remaining 42 aneurysms having been discovered and clipped during surgery for a ruptured aneurysm. All isolated unruptured aneurysms were detected by angiography, computerized tomography or magnetic resonance imaging. Twenty out of the 89 aneurysms were asymptomatic ("incidental") while 69 were accompanied by clinical symptoms indicating radiological examination. It is generally accepted that in ruptured aneurysms the mortality rate during 3 days following the rupture is about 50 percent, and for this reason many neurosurgeons are in favour of unruptured aneurysms being treated either by open surgery with clipping of the aneurysmal neck or by inserting a balloon into the aneurysmal sac. The results obtained in 377 published cases, including ours, justify this approach: no recurrent bleeding was observed after open surgery and the mortality rate was nil when the contra-indications of surgery were respected. There was a permanent morbidity of less than 2 per cent directly related to the surgeon's experience.

Classification of supratentorial arteriovenous malformations. A score system for evaluation of operability and surgical strategy based on an analysis of 66 cases.

A classification of arteriovenous malformations (AVM) is proposed, which is based on a retrospective analysis of the records and results of radical operation in 57 patients between 1983 and 1990. It represents the new developments and more recent technical facilities which influence operability of supratentorial AVMs. Predictability of outcome has been settled upon three groups of factors: anatomical, haemodynamical, and clinical. Anatomical factors are localisation and sectorisation of AVM, determination, caliber and straightening of feeding arteries. Haemodynamical factors are volume of AVM and vascular autoregulation, circulatory velocity of red blood cells in the main arteries of the neck and brain tissue cellular steal. Clinical factors are age, previous rupture of AVM, associated diseases and malformations of vital organs. Each of these factor groups has been divided into parameters to which a code number from 0 to 5 according to the severity of the considered parameter has been attributed. When a contraindication for radical surgery was clearly obvious, as, for example, an AVM with extension to the upper brain stem, number 10 was given. This grading has been done by a team of four persons (3 neurosurgeons including the senior author, and one biophysicist). By adding up all code numbers an Operability Score for a given patient is defined by the number of points, with a minimum of 3 and a maximum of 69. In cases with a score higher than 30 surgery is not advisable. A score between 21 and 30 indicates that always several staged operations are required, whilst only some of the patients with a score between 11 and 20 may require two stage operative treatment. The AVM in patients with a score under 10 can always be radically excised in a single stage operation. We have been able to demonstrate that the Operability Score allows a reliable prediction of outcome, thus giving indications and contraindications for surgery, and also for the surgical strategy. Moreover, we have explained why surgery had been refused in 9 additional cases during the same period. The causes of 8 fatalities out of 57 surgical cases are analyzed. These 57 cases represent a systematically explored series of the senior author; his experience is based upon 295 personal AVM cases (1958-1990).

Rapid detection of pseudorabies virus genomic sequences in biological samples from infected pigs using polymerase chain reaction DNA amplification.

The presence of the pseudorabies virus (PRV) genome in infected hosts has previously been studied by standard hybridization techniques, which showed the viral genome to be present at very low levels in infected tissues. The recently introduced polymerase chain reaction (PCR) procedure provides an alternative and rapid means of amplifying small quantities of specific DNA sequences. We applied this technique to a study of pigs infected by PRV. The sequence selected for amplification consisted of 222 base pairs lying in the gene coding for the glycoprotein gp50. We used a pair of 20-mer oligonucleotides flanking this sequence as primer and a cloned Stu-Nde fragment containing the sequence as target DNA. To avoid the tedious DNA extraction procedure we performed PCR directly on disrupted cells and detected specific amplification after 25 cycles of PCR with the thermostable Taq DNA polymerase. Amplified products were detected by gel electrophoresis directly. Nasal samples from experimentally and naturally infected pigs were tested by this PCR technique. When compared with tissue culture and serological tests, detection by gel electrophoresis of PCR amplified fragments provided excellent specificity and sensitivity. We concluded that PCR amplification will be a valuable tool for rapid diagnosis of PRV infection in pigs, taking less than 1 h to complete.

Haemostatic clips and clamps used in surgical neurology with special reference to non ferro magnetic Phynox spring clips by Aesculap.

This paper concerns the historical developments and technical properties of haemostatic devices used in neurosurgery with the exception of coagulation. Therefore there are described haemostatic clips designed for the scalp, clips used on arteries and veins, a clamp for the reduction of the carotid diameter in the neck, and a clamp for closing the venous dural sinuses. Special reference will be made regarding non ferro magnetic Phynox clips by Aesculap.

A new haemodynamic factor in cerebral AVM. Aspiration from the venous system demonstrated in two cases of pedonculo-Galen AVM successfully cured by occlusion of the superior longitudinal sinus.

Using a Doppler Mark 500 of ATL we measured the systolic and diastolic velocity of the red cells into the main arteries of the neck (diastolic rate cm/sec) thus approaching the flow in two cases of upper brain stem AVM with a unique drainage into the superior longitudinal sinus through an enlarged vein of Galen and a falcine sinus. Because of the desperate clinical condition of the children it was decided to stop the high blood flow by closing the aspiration coming from the low pressure of the venous system above and below the site of union between the malformation and the superior longitudinal sinus. An intra-operative and post-operative measurement of the diastolic rate showed a radical effect of the closure of the superior longitudinal sinus. The demonstration of this aspirative factor has allowed us to classify an AVM as a haemodynamic push-pull malformation.

Physical mapping and nucleotide sequence of a herpes simplex virus type 1 gene required for capsid assembly.

In this report, we describe some phenotypic properties of a temperature-sensitive mutant of herpes simplex type 1 (HSV-1) and present data concerning the physical location and nucleotide sequence of the genomic region harboring the mutation. The effect of shifts from the permissive to the nonpermissive temperature on infectious virus production by the mutant A44ts2 indicated that the mutated function is necessary throughout, or late in, the growth cycle. At the nonpermissive temperature, no major differences were detected in viral DNA or protein synthesis with respect to the parent A44ts+. On the other hand, electron microscopy of mutant-infected cells revealed that neither viral capsids nor capsid-related structures were assembled at the nonpermissive temperature. Additional analyses employing the Hirt extraction procedure showed that A44ts2 is also unable to mature replicated viral DNA into unit-length molecules under nonpermissive conditions. The results of marker rescue experiments with intact A44ts2 DNA and cloned restriction fragments of A44ts+ placed the lesion in the coordinate interval 0.553 to 0.565 (1,837 base pairs in region UL) of the HSV-1 physical map. No function has previously been assigned to this region, although it is known to be transcribed into two 5' coterminal mRNAs which code in vitro for a 54,000-molecular-weight polypeptide (K. P. Anderson, R. J. Frink, G. B. Devi, B. H. Gaylord, R. H. Costa, and E. K. Wagner, J. Virol. 37:1011-1027, 1981). We sequenced the interval 0.551 to 0.565 and found an open reading frame (ORF) for a 50,175-molecular-weight polypeptide. The predicted product of this ORF exhibits strong homology with the product of varicella-zoster virus ORF20 and lower, but significant, homology with the product of Epstein-Barr virus BORF1. For the three viruses, the corresponding ORFs lie just upstream of the gene coding for the large subunit of viral ribonucleotide reductase. The ORF described here corresponds to the ORF designated UL38 in the recently published nucleotide sequence of the HSV-1 UL region (D. J. McGeoch, M. A. Dalrymple, A. J. Davison, A. Dolan, M. C. Frame, D. McNab, L. J. Perry, J. E. Scott, and P. Taylor, J. Gen. Virol. 69:1531-1574, 1988).

[Successful separation in 1974 of craniopagus twins united at the vertex. Indications, technics, follow-up after 14 years]. / Séparation réussie en 1974 de jumelles craniopages unies par le vertrex. Indications, techniques, évolution sur 14 ans.

On July 22, 1974, 55 days after delivery, the separation of female craniopagus twins united at the vertex was performed. This case was very similar to the case published by Voris in 1957 after separation in 1955. Surgery was decided because the neurological examination was normal in both twins, because there was no body malformation, because the angiogram as well as isotopic scintigraphy showed two normal brains, two superior sagittal sinuses and two torcular areas with a short venous union in the middle of the bone defect. In addition, Sophie and Sonia were suffering from respiratory disturbances due to their position. Surgery was easy (90 min) using the operative microscope; intubation and placing intravascular tubes for hemodynamic monitoring were difficult and lasted 4 hours. After all it took 14 years and 23 operations to complete the reconstructive surgery of the bone and skin. Cranioplasty was finally performed using vitallium plates. On their 14th birthday a neuropsychological investigation was performed with an IQ of 94 in Sophie and 76 in Sonia. Both girls are nubile and enjoy a normal school attendance.

Detection of a ruptured aneurysmal sac by MRI in a case of negative angiogram. Successful clipping of an anterior communicating artery aneurysm. Case report.

A case of a ruptured aneurysm is presented in which the angiograms did not disclose the sac. Rupture of an aneurysm of the anterior communicating artery was suspected from the distribution of subarachnoid blood on computerized tomography (CT), and the presence of a sac was highly suggestive on magnetic resonance imaging (MRI), which led us to open surgery. A non-thrombosed aneurysm was discovered at the suspected site, and successfully clipped. The necessity is discussed of MRI investigation in patients with subarachnoid haemorrhage (SAH) of unknown aetiology.

Steroid receptor status difference in recurrent intracranial meningioma and breast cancer in the same patient.

The authors report a case of multiple recurrent intracranial meningioma associated with breast cancer in a menopausal woman. High affinity estrogen (ER) and progestin receptors (PR) were assayed independently in the meningioma and the tumor. ER were found to be very low in the meningioma and high in the breast tumor. On the contrary PR were found to be high in the meningioma and could be not detected in the breast tumor. This unique case suggests that meningioma and breast cancer are not under the same type of hormonal influence.