Multiple developmental requirements of noisette, the Drosophila homolog of the U2 snRNP-associated polypeptide SP3a60

We report the cloning of the noisette gene (noi), which encodes the Drosophila melanogaster ortholog of a U2 snRNP-associated splicing factor, SF3a60 (SAP61) in humans and PRP9p in Saccharomyces cerevisiae. Antibodies raised against human SF3a60 recognized NOI in flies, showing a nuclear localization in all the stages examined, including the embryo, the dividing cells of imaginal discs, and the larval polyploid nuclei. NOI is expressed in somatic and germinal cells of both male and female gonads. By mobilization of P transposons, we have generated a large number of noi mutations. Complete loss of function resulted in lethality at the end of embryogenesis, without obvious morphological defects. Hypomorphic alleles revealed multiple roles of noi for the survival and differentiation of male germ cells, the differentiation of female germ cells, and the development of several adult structures.

New AUG initiation codons in a long 5' UTR create four dominant negative alleles of the Drosophila C2H2 zinc-finger gene ovo

Promoters active in the germline produce OVO-A and OVO-B mRNAs encoding isoforms of a putative transcription factor. The isoforms have a common C2H2 zinc-finger domain but different N-termini that include potential effector domains. Single point mutations in three dominant-negative ovoD mutations result in new in-frame initiation codons in OVO-B mRNAs and amino acid substitutions within charged regions of OVO-A proteins. Three lines of evidence suggest that the dominant activity is due to the new initiation codons in OVO-B mRNAs and not the amino acid substitutions in OVO-A. First, we made a fourth ovoD allele by inserting a new in-frame AUG. This ovoD4 allele encodes a nearly full-length OVO-A isoform from OVO-B mRNAs. Second, engineered stop codons in ovoD1 downstream of the new AUG abolished dominant negative activity. Third, a substantial deletion of an OVO-A region encoding a highly charged amino acid domain fully rescued loss-of-function ovo alleles. These data suggest that ovoD mutations result in inappropriate expression of OVO-A in the female germline.

Impaired estimation of word occurrence frequency in frontal lobe patients

Neuroanatomical correlates of the estimation of occurrence frequency have received little attention. This study investigates the possible role of the frontal lobe in estimating word occurrence frequency. A sample of 27 patients with frontal lesions were matched with normal controls by sex, age and years of education. Significant differences between patients and controls were found for frequency estimation, but not for item recognition. Studying accuracy of estimation as a function of actual frequency, the frontal group performed worse, especially at high frequencies of occurrence. As far as lesion lateralization is concerned, the right frontal subgroup performed worse than the control group in the estimation of frequency. Our results suggest that the prefrontal cortex plays a role in estimating word occurrence and that there is a dissociation between frequency memory and recognition memory, pointing to the involvement of two different cerebral systems.

A retrospective six-months clinical trial of adhesive precoated brackets and bonding system

This study investigated bond failures in two groups of 75 patients. Either adhesive precoated (APC) or control brackets were bonded from bicuspid to bicuspid in the mandibular and maxillary arch by a single experienced operator. Observations on failure were recorded at initial arch wire insertion and for the first six months of treatment. The APC bracket failed significantly more often than the control at initial arch wire insertion in both maxillary and mandibular teeth. Further examination disclosed that the APC bracket, when bonded to mandibular teeth, also failed significantly more often than the control during the subsequent six months of treatment. At the six-month point of the study, a total of 53 bond failures had occurred at 671 bond sites in the APC group (7.89 per cent failure rate), compared to 27 bond failures at 977 bond sites in the control group (2.76 per cent failure rate). Fourteen patients in the APC group and two patients in the control group experienced bond failure at initial arch wire insertion. Twenty-eight patients in the APC group and 13 in the control group experienced bond failures within the first six months following initial arch wire insertion.

Sharp increase in rat lung water channel expression in the perinatal period

Three members of the water channel (aquaporin) family are expressed in adult rat lung: CHIP28 (AQP-1), MIWC (AQP-4), and AQP-5. Because water channels may be important in the clearance of fluid from the newborn lung, the expression of water channels just before and after birth was investigated using the ribonuclease (RNAse) protection assay. RNA was isolated from lungs, brain, and heart of prenatal rats (fetal days F19, F20, and F21) and postnatal rats (days +1, +2, +5, +7, +21, and adult). Transcript expression was measured relative to a beta-actin control by quantitative densitometry. Whereas beta-actin mRNA expression was nearly constant over time, distinct expression patterns were observed for the three water channels. CHIP28 mRNA expression rose slowly from days F19 to +1, then strongly at day +2, and remained elevated over the first week. MIWC mRNA was weakly expressed prenatally, but strongly increased just after birth. AQP-5 mRNA increased slowly and monotonically between days F20 and +7. These patterns contrasted sharply with the developmental expression of CHIP28 in heart, which decreased over time, and MIWC in brain. Immunocytochemistry showed CHIP28 protein expression in capillary endothelia and MIWC in airway epithelia by day +1; quantitative immunoblot analysis showed increased CHIP28 protein expression over time. These findings are consistent with a role of lung water channels in perinatal fluid clearance; however, proof of physiologic significance will require functional measurements of air space-capillary water permeability.

Suboccipital dermatomyotomic stimulation and digital blood flow

The effect of gentle, soft tissue manipulation in the suboccipital region on digital blood flow, as a measure of sympathetic nervous system activity, was studied. Digital strain gauge plethysmography was used to measure the changes in pulse contour during (1) a normative test period with the subject in the supine position, (2) after a control interval (placebo) during which the investigator placed his hands under the suboccipital region, and (3) after an interval during which the investigator's fingers applied slow, steady, circular kneading in the suboccipital triangle region. Twenty-five studies were performed in a crossover design with the patient as his or her own control. Total pulse amplitude (Y) and the height from the dicrotic notch to the peak (X) were measured. Examination of the total data of all subjects revealed the occurrence of a significant change in X and Y with simply touching the suboccipital region with the hands. An even more favorable response ensued when suboccipital manipulation was applied. Those subjects reporting comfort or neutral responses had larger significant changes with manipulation when compared with the group reporting the experience as uncomfortable. The response within each group suggests that favorable autonomic changes (sympathetic dampening) occur with specific suboccipital manipulation as well as, indeed, the simple touching of the suboccipital triangle.

Flow cytometry analysis of pituitary adenomas

Using flow cytometry, DNA content and index, and/or proliferative capacity (measuring proliferating cell nuclear antigen PCNA) in operated pituitary tumors, control pituitaries obtained at necropsy, and experimental pituitary hyperplasia induced in rats were analyzed. Simultaneous measurement of cell ploidy and proliferation differentiated normal pituitary (diploid DNA index and negative PCNA) from pituitary hyperplasia (diploid DNA index with intensely positive PCNA, between 30 and 72% of cells). In the tumors 83% (19/ 23) were positive for PCNA (between 3 and 84%) and 73% (17/23) aneuploid; only 1 tumor was diploid and negative for PCNA.

CONCLUSIONS

Differentiation between normal and abnormal (neoplastic or hyperplastic) pituitary is possible by flow cytometry, but in the adenomas no correlation with postoperative clinical outcome was observed.

A phenomenological study of sensory defensiveness in adults

This article describes the experiences of five adults who are defensive toward sensations of touch, movement, vision, smell, sound, and taste that most people consider harmless. It also describes the strategies that they use when they perceive environmental stimuli to be aversive. These coping strategies are avoidance, predictability, mental preparation, talking through, counteraction, and confrontation. A conceptual framework is presented to enhance understanding and guide further study of sensory defensiveness in adults.

Identification of regions interacting with ovoD mutations: potential new genes involved in germline sex determination or differentiation in Drosophila melanogaster

Only a few Drosophila melanogaster germline sex determination genes are known, and there have been no systematic screens to identify new genes involved in this important biological process. The ovarian phenotypes produced by females mutant for dominant alleles of the ovo gene are modified in flies with altered doses of other loci involved in germline sex determination in Drosophila (Sex-lethal+, sans fille+ and ovarian tumor+). This observation constitutes the basis for a screen to identify additional genes required for proper establishment of germline sexual identity. We tested 300 deletions, which together cover approximately 58% of the euchromatic portion of the genome, for genetic interactions with ovoD. Hemizygosity for more than a dozen small regions show interactions that either partially suppress or enhance the ovarian phenotypes of females mutant for one or more of the three dominant ovo mutations. These regions probably contain genes whose products act in developmental hierarchies that include ovo+ protein.

Function of Drosophila ovo+ in germ-line sex determination depends on X-chromosome number

Germ-line sex determination in Drosophila melanogaster requires an assessment of the number of X chromosomes as measured against autosomal standards (XX = female, X = male) and signaling from the soma. Both of these sex determination cues are required for female-specific Sex-lethal+ function in germ cells. The ovo+ locus encodes zinc finger protein(s) required for female-specific splicing of Sex-lethal+ pre-mRNA, making ovo+ a candidate function acting between the two principal cues and Sex-lethal+. We have made ovo reporter genes and find that they show high activity in the germ line of females and low activity in the germ line of males. XY flies transformed into somatic females do not show high levels of reporter activity, while XX flies transformed into somatic males do. This shows that high level ovo+ expression depends on the number of X chromosomes, not the somatic sexual signals. The requirement for ovo+ function is restricted to XX flies. Mutations in ovo have no effect on XY males, X0 males or XY females, but have pronounced effects on germ cell viability in XX females, XX females with sex transformed germ lines, and XX males indicating that ovo+ gene products are required for events occurring only in flies with two X chromosomes.

Check records--a chairside mounting procedure

This article considers the logistical problems involved when the check (interocclusal) record procedure is used to remount complete dentures on an articulator. It reports the development of upper and lower "check record mounting blocks" that may be made to fit any articulator, thus enabling the procedure to be performed easily and quickly at chairside.

Parvalbumin and calbindin-D28k immunocytochemistry in human neocortical epileptic foci

Serial sections of cortical resection of 30 patients suffering from drug-resistant epilepsy were processed for parvalbumin and calbindin-D28k immunocytochemistry to determine local circuit neuron populations. Our findings indicate that there is not a simple mechanism to explain neocortical epileptic foci. On the basis of the present results it can be suggested that: (1) reduced percentage of local circuit neurons in the vicinity of neoplasms may account for a decreased intracortical inhibition. (2) Abnormal morphology and distribution of local circuit neurons may result in abnormal cortical inhibition in patients with focal cortical dysplasia, and, probably, in other focal migrational disorders, including neuronal nests in the white matter. (3) Increased percentages of immunoreactive local circuit neurons and fibers in focal neocortical necrosis (cavernous angiomas), diffuse hypoxic encephalopathy, and hippocampus in patients with temporal lobe epilepsy due to mesial sclerosis, may play a role in epilepsy. These neurons can be activated by reduced excitatory inputs, or they may establish abnormal synaptic contacts with other inhibitory neurons. (4) Lack of consistent morphologic abnormalities in the neocortex of patients with temporal lobe epilepsy, and in patients with cryptogenetic frontal lobe epilepsy, suggests that electrically abnormal neocortical foci in these cases are probably epiphenomena.

What is needed for resective epilepsy surgery from a neurosurgical point of view?

Invasive versus non-invasive epileptogenic zone definition was analyzed in a series of 89 patients operated on for drug-resistant epilepsy. In the group of 69 cortical resections, 26% needed invasive recordings, 13.5% when foreign-tissue lesions had been detected by MRI and 32% when were absent. In this last group temporal resections had invasive EEG recordings in 23.5% versus 54.5% when the epileptogenic zone was extratemporal. In a group of 43 temporal resections with more than one year follow-up MRI has detected some abnormality in 84%. Excluding focal lesions, MRI detected hippocampal/temporal lobe atrophy in 66% of the cases in agreement with other noninvasive tests and in 4% contralateral to the epileptogenic zone located by subdural strips. The outcome analysis showed that 85% of the patients with MRI-EEG agreement were seizure free in contrast to only 43% when MRI was non-lateralizing. Future studies has to be oriented to better understand the epileptic process of patients without MRI abnormalities.

[The tethered cord syndrome : a review of causes]

We present eighteen cases with Tethered cord syndrome (TCS). They were eleven adults and eight children. There were eight cases with surgical interventions performed in other centers during the newborn period for different types of spinal disraphisms. Clinical onset was insidious in 88% of the cases, and in 12% of the cases was acute, due to a precipitating factor. The main clinical findings were neurological skeletal , urological and cutaneous alterations in variable frequencies. Magnetic resonance imaging (MRI) was the best diagnostic test. Urodynamic studies in patients with urological alterations were abnormal and they helped to establish additional pharmacological treatment. After surgery 88% of the patients had an improvement or an arrest in the progression of the symptoms. Patients with shorter duration of the symptoms (less than 2 years) had a better prognosis.

Evidence for sex transformation of germline cells in ovarian tumor mutants of Drosophila

Mutations at a few genetic loci in Drosophila cause ovarian tumors with hundreds of poorly differentiated germ cells. We examined several of these mutants to test the hypothesis that such ovarian tumors contain sex-transformed cells. By testing for expression of male germline traits, we determined that partial germline sex transformation occurs in otu, snf, Sxlfs, and bam ovarian tumors. Thus these genes are likely to be required for proper establishment of germline sexual identity.

Sex-lethal, master and slave: a hierarchy of germ-line sex determination in Drosophila

Female sex determination in the germ line of Drosophila melanogaster is regulated by genes functioning in the soma as well as genes that function within the germ line. Genes known or suspected to be involved in germ-line sex determination in Drosophila melanogaster have been examined to determine if they are required upstream or downstream of Sex-lethal+, a known germ-line sex determination gene. Seven genes required for female-specific splicing of germ-line Sex-lethal+ pre-mRNA are identified. These results together with information about the tissues in which these genes function and whether they control sex determination and viability or just sex determination in the germ line have been used to deduce the genetic hierarchy regulating female germ-line sex determination. This hierarchy includes the somatic sex determination genes transformer+, transformer-2+ and doublesex+ (and by inference Sex-lethal+), which control a somatic signal required for female germ-line sex determination, and the germ-line ovarian tumor genes fused+, ovarian tumor+, ovo+, sans fille+, and Sex-lethal+, which are involved in either the reception or interpretation of this somatic sex determination signal. The fused+, ovarian tumor+, ovo+ and sans fille+ genes function upstream of Sex-lethal+ in the germ line.

The role of the ovarian tumor locus in Drosophila melanogaster germ line sex determination

The locus ovarian tumor (otu) is involved in several aspects of oogenesis in Drosophila melanogaster. The possible role of otu in the determination of the sexual identity of germ cells has not been extensively explored. Some otu alleles produce a phenotype known as ovarian tumors: ovarioles are filled with numerous poorly differentiated germ cells. We show that these mutant germ cells have a morphology similar to primary spermatocytes and that they express male germ line-specific reporter genes. This indicates that they are engaged along the male pathway of germ line differentiation. Consistent with this conclusion, we found that the splicing of Sex-lethal (Sxl) pre-mRNAs occurs in the male-specific mode in otu-transformed germ cells. The position of the otu locus in the regulatory cascade of germ line sex determination has been studied by using mutations that constitutively express the feminizing activity of the Sxl gene. The sexual transformation of the germ cells observed with several combinations of otu alleles can be reversed by constitutive expression of Sxl. This shows that otu acts upstream of Sxl in the process of germ line sex determination. Other phenotypes of otu mutations were not rescued by constitutive expression of Sxl, suggesting that several functions of otu are likely to be independent of sex determination. Finally, we show that the gene dosage of otu modifies the phenotype of ovaries heterozygous for the dominant alleles of ovo, another gene involved in germ line sex determination. One dose of otu+ enhances the ovoD ovarian phenotypes, while three doses partially suppress these phenotypes. Synergistic interaction between ovoD1 and otu alleles leads to the occasional transformation of chromosomally female germ cells into early spermatocytes. These interactions are similar to those observed between ovoD and one allele of the sans fille (snf) locus. Altogether, our results imply that the otu locus acts, along with ovo, snf, and Sxl, in a pathway (or parallel pathways) required for proper sex determination of the female germ line.

[Anesthesia in surgery for epilepsy]

OBJECTIVES

To evaluate the efficacy of general anesthesia during epileptic surgery.

MATERIAL AND METHODS

A retrospective study of 64 patients who received general anesthesia during epileptic surgery. In the preoperative period, anticonvulsive medication was adjusted in accordance with plasma levels and withdrawn entirely 8 hours before surgery. After premedication with droperidol and fentanyl, a balanced anesthetic technique was applied, based on pentothal, pancuronium (or vecuronium), fentanyl, N2O and isoflurane. Continuous monitoring of ECG, arterial blood pressure, pulse oximetry, ET CO2 and neuromuscular function. Isoflurane was stopped for 10 min after the opening of the duramadre so that ECoG could be recorded and methohexital or propofol was given in some cases in order to activate the epileptogenic focus. Muscular relaxation was restored intraoperatively following the study of somatosensory evoked potentials. Immediate and later complications related to anesthesia or surgery were recorded.

RESULTS

The surgical procedure performed in most cases was temporal or frontal resection, with a mean duration for anesthesia of 377 +/- 50 min and for surgery of 318 +/- 50 min. Only one patient received local anesthesia and no hemodynamic changes were observed. Perioperative complications were cerebral edema (4 cases), arrhythmia (2 cases) and bronchospasm (1 case). Postoperative complications were as follows: 3 of 9 patients undergoing callosotomy required mechanical ventilation for 24 hours, 4 patients experienced language alterations, 3 wounds were infected, 2 cases of hemiplegia were observed, 1 status epilepticus occurred after administration of propofol and there was 1 case of respiratory distress. Anticonvulsive medication was given parenterally after surgery.

CONCLUSIONS

General anesthesia is a safe and effective method for epileptic surgery, with local anesthesia providing additional sedation for isolated cases. Appropriate treatment requires an understanding of the pharmacokinetics and pharmacodynamics of the drugs used, as well as knowledge of the condition and the anticonvulsive medications used.

Role of tyrosine kinase and phosphotyrosine phosphatase in growth of the intestinal crypt cell (IEC-6) line

The roles of gastrin and sodium vanadate in proliferation were examined in cultured IEC-6 cells that are mitotically active and derived originally from jejunal crypts of the rat intestine. Incubation of the cells in the presence of gastrin at a concentration of 250 ng/ml or of sodium vanadate at a concentration of 0.2 mM leads to a 60% increase in cell growth in 24 hr. The stimulated growth in both cases was inhibited by genistein, a tyrosine kinase inhibitor. Incubation in the presence of gastrin and sodium vanadate together produced a small, albeit significant, potentiation of growth of the cells. Gastrin as well as sodium vanadate also promoted the phosphorylation on tyrosine of a similar group of proteins with molecular masses of 42, 45, 52, 60, 78, and 120 kDa. The phosphorylations were rapidly occurring as early as 5 min and lasted for only 15 min. Several proteins were detected in normal IEC-6 cells, including GTPase activating protein, raf1 kinase, phospholipase C gamma-1, and phosphoinositide 3-kinase. The results suggest that gastrin and sodium vanadate induce growth of IEC-6 cells by stimulation of tyrosine kinase and/or inhibition of tyrosine phosphatase. The gastrin and sodium vanadate effects also involve the phosphorylation of a number of proteins, the identities of which are not known at present but may include some of the kinases that are frequently associated with cell growth, such as mitogen-activated protein kinase, raf1 kinase, phosphoinositide 3-kinase, and others.