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E Gay

Publications and source records attributed to E Gay.

At least 19 recordsLinked to original sources
PubMed2001

Disparities in hormone replacement therapy use by socioeconomic status in a primary care population.

The use of hormone replacement therapy (HRT) is a controversial decision for many women, yet few studies have evaluated the socio-demographic, psychological, and behavioral correlates of HRT use. This cross-sectional, mailed survey evaluated the associations of socioeconomic status, preventive health behaviors, knowledge and perceptions about HRT-related risks and benefits with HRT use among 428 women 50-70 years old in Vermont. The overall prevalence of HRT use was 40%. Women of moderate to high income were three times more likely than those of low income to use HRT. HRT use was significantly higher among women whose physician had encouraged use (58%) than among those who received ambivalent recommendations from their physicians (20%). Hysterectomy, higher income, younger age, regular adherence to cervical cancer screening, and recommendation by a provider were significantly associated with HRT use in multivariate analyses. There were no differences in HRT use according to level of concern about heart disease, osteoporosis, or breast cancer. A recommendation by a health care provider is a powerful predictor of HRT use, but disparities in use exist by socioeconomic status. Future research should examine why lower income women are less likely to use HRT and whether the discrepancy is due to inconsistent recommendations by health care providers.

Aged↗
PubMed2000

AUUUA sequences compromise human insulin-like growth factor binding protein-1 mRNA stability.

The instability of IGFBP-1 mRNA appears to play a role in regulating the expression of the IGFBP-1 gene, the 3' region of which contains five ATTTA sequences. We have studied the implication of these sequences for IGFBP-1 mRNA destabilization. Six plasmids were constructed, containing increasingly shorter lengths of IGFBP-1 cDNA, each with a successive ATTTA sequence deleted from the 3' end. These were stably transfected into two non-IGFBP-1-expressing (cervical carcinoma and neuroblastoma) cell lines. Kinetics studies following inhibition of transcription showed that (1) the half-life of the full-length messenger was 2.80 +/- 0.32 h; (2) deletion of each successive sequence (particularly the second and the fourth) yielded a transcript of increasing stability; and (3) the half-life of the AUUUA-free mRNA was 26.65 +/- 1.65 h. Although the primary source of IGFBP-1 is the liver, our results demonstrate that destabilization of its mRNA is not liver-specific. The ATTTA consensus sequences in the 3' untranslated region of the IGFBP-1 gene therefore provide a posttranscriptional regulation pathway that, combined with transcriptional regulation, may account for the variations in IGFBP-1 expression with developmental stage, nutritional status, and hormonal environment.

3' Untranslated Regions↗
PubMed2000

Probing magnetic properties of the reduced [2Fe-2S] cluster of the ferredoxin from Arthrospira platensis by 1H ENDOR spectroscopy.

The 1H electron nuclear double resonance (ENDOR) spectra in frozen solutions of the reduced [2Fe-2S] cluster in ferredoxin from Arthrospira (Spirulina) platensis have been measured at low temperatures (5-20 K) and simulated using orientational selection methods. The analysis confirmed the existence of a single paramagnetic species with iron valence states II and III connected uniquely to the cluster irons. The experimental ENDOR spectra were fitted to a model including the spin distribution on the centre, the orientation of the g-matrix, and the isotropic and anisotropic hyperfine couplings of the nearest protons in the crystallographically determined structure. In order to partially simulate ENDOR line shapes, a statistical distribution of the corresponding torsion angles between the Fe(III) centre and one of the beta-CH2 protons was introduced. From the analysis, four of the larger hyperfine couplings found were assigned to the cysteine beta-protons near the Fe(III) ion of the cluster, with isotropic hyperfine couplings ranging from 1.6 to 4.1 MHz. The spin distribution on the two iron ions was estimated to be +1.85 for the Fe(III) ion and -0.9 for the Fe(II) ion. The Fe(III) ion was identified as being coordinated to the cysteine ligands Cys49 and Cys79, confirming previous NMR results. The direction of the g-tensor with respect to the cluster was deduced. The g1-g2 plane is parallel to the planes through each iron and its adjacent cysteine sulfurs; the g2-g3 plane is nearly perpendicular to the latter planes and deviates by 25 degrees from the FeSSFe plane. The g1 direction is dominated by the bonding geometry of Fe(II) and does not align with the Fe(II)-Fe(III) vector.

Cyanobacteria↗
PubMed2000

Management of craniocervical junction dislocation.

The discovery of a craniocervical junction malformation requires management in three steps: (1) The patterns must be recognized using tomographic measurements (Chamberlain's line, Wackenheim's line). Dynamic flexion-extension studies are necessary to assess stability or instability. Stable patterns range from platybasia to basilar invagination, with gradual deformation, and are frequently associated with Chiari malformation. Unstable patterns characterized by odontoid instability are the equivalent of an odontoid fracture. The origin is malformative (hypoplasia, aplasia of the dens, os odontoidum), but the last may be difficult to distinguish from an old odontoid fracture. They are found in many syndromes (Down, Morquio, etc.). Unstable atlantoaxial patterns with atlas assimilation are hardly reducible; they evolve toward progressive instability. (2) The neurological consequences must be defined from the clinical features of the spinal cord and the cranial nerves. Both static and dynamic MRI scans must be performed; in this way identification of the neural abnormalities (hydromyelia, Chiari, etc.) and of the osseous compression is possible. (3) The most appropriate operative procedure must be selected: stable platybasia with a nervous compression by Chiari is cured only by posterior decompression; odontoid instability is cured by reduction and posterior fixation, using hooks and autologous bone grafts on the posterior arches of C-1 and C-2. Sometimes a transarticular screw fixation of C1-2 is necessary if there is a defect on the C-1 posterior arch. Craniocervical dislocations with assimilation of the atlas require posterior occipito-vertebral bony fixation with grafts and external halo immobilization or internal fixation with hooks or screws, with anterior transoral decompression in a second step.

Arnold-Chiari Malformation↗
PubMed2000

Analysis of the turin umbilical cord blood bank registry.

BACKGROUND: The polymorphic nature of the HLA system reduces a patient's probability of finding an HLA-compatible unrelated bone marrow (BM) donor, even though more than 6 million individuals are enrolled in international registries. Recently, umbilical cord blood (UCB) has been successfully employed as a source of HPCs. The use of such cells reduces the risk of GVHD and allows transplants with one or two HLA mismatches. UCB represents an expensive resource: therefore, it is necessary to carefully manage the UCB unit inventory. STUDY DESIGN AND METHODS: The current study analyzed the genetic heterogeneity of HLA-A, -B, and -DR gene frequencies between pools of UCB and unrelated-donor BM in the Piedmont (an administrative region of Italy). An Italian hematology patient's probability of finding complete or partial matches as a function of donor pool size was determined by considering subsamples randomly selected from the local unrelated BM donors. RESULTS: The HLA gene frequencies in UCB and unrelated-donor BM pools were not significantly different. The search simulation, based on actual HLA phenotypes, showed that the percentage of Italian patients matched with an HPC unit increases remarkably if 1 or 2 mismatches are accepted, reaching a proportion of 90 percent with an inventory of only about 500 units, while the increment is not so remarkable if the number of UCB units is greater. CONCLUSION: To optimize economic resources and to be internationally competitive, UCB banks should aim to increase the genetic heterogeneity of their units rather than increasing the UCB inventory, acquire efficient quality control systems, and acquire and preserve UCB units with a greater number of nucleated cells.

Blood Banks↗
PubMed1998

[Unusual approaches to hypophyseal adenomas].

For pituitary adenomas surgery, rhinoseptal transsphenoidal approach is used in 98 to 99% of the cases. Although this approach is fitting for microadenomas and the majority of macroadenomas, some of them develop extensions in the nasal fossas, the posterior cranial fossa, the suprasellar region, or into the cavernous sinus and will require other approaches. For the superior routes, the frontopterional approach gives good control of the suprasellar region, the anterior and middle base of the skull. The tumor dissection is performed inside the concavity of the chiasm and between the internal carotid artery and the optic nerve (optico-carotid approach). The frontopterional approach is used for superolateral extensions, especially in the lateral fissure. The bifrontal basal inter hemispheric approach, through a medial frontal bone flap tangential to the base, gives a good route to the suprasellar region and behind the dorsum, and also for tumors extended in the third ventricle in case of prefixed chiasm. For the inferior routes, the participation of ENT or craniofacial surgeons is a great help. The transfacial or transethmoidal approach performs a hollowing of the nasal fossas and gives a large interorbital tunnel adapted for tumors extended in the rhinopharynx and the ethmoid. The Le Fort I maxillary osteotomy offers also a large approach for adenomas extending in the rhinopharynx. The transcavernous approach from Dolenc, for adenomas progressing in the cavernous sinus requires a long and difficult procedure. The progression of some adenomas in many directions may require a combined approach in one or two procedures.

Adenoma↗
PubMed1997

Liver-specific expression of human insulin-like growth factor binding protein-1 in transgenic mice: repercussions on reproduction, ante- and perinatal mortality and postnatal growth.

Study of the in vivo functions of the insulin-like growth factor binding proteins (IGFBPs) is complicated by their variety (six molecular species) and the differences in their expression related to tissue of origin and stage of development. To investigate the physiological role of IGFBP-1 in the bloodstream, we induced hepatic overexpression of IGFBP-1 in transgenic mice, placing human IGFBP-1 (hIGFBP-1) cDNA under the control of the alpha1-antitrypsin promoter so as to obtain liver-specific expression. Five transgenic founder mice were raised, only two of which (lines 124 and 149) produced transgenic offspring. Northern blotting revealed transgene expression exclusively in the liver during fetal life and unchanged through to adulthood, whereas expression of the endogenous gene was undetectable beyond 10-15 days postnatally. hIGFBP-1 was detected by western immunoblotting in the plasma of transgenic mice and IRMAs yielded mean concentrations of 2.41 +/- 0.33 ng/ml and 13.69 +/- 1.42 ng/ml in homozygous animals of lines 124 and 149, respectively. In the latter, IGFBP-1 levels were distinctly higher than in heterozygotes (2.99 +/- 0.39 ng/ml), P < 0.0001. These levels remained stable in each given animal and did not change with age. Plasma concentrations of IGF-I measured in line 149 exhibited the well-known profile of an increase from birth up to puberty. Values for heterozygotes were similar to those for wild-type mice, with adult levels (544 +/- 98 ng/ml) slightly below those of controls (630 +/- 56 ng/ml), P < 0.05. In homozygotes they were distinctly lower, with adult levels of 370 +/- 75 ng/ml, P = 0.001. In heterozygous and homozygous adults, there was a negative correlation between IGF-I and IGFBP-1 concentrations (r = 0.8, P < 0.0001), suggesting a link between transgene expression and IGF-I levels. Study of body weight gain in line 149 revealed growth retardation within the first weeks after birth, which was marked in homozygous males and females (P < 0.001) but also present in heterozygous males (P = 0.002), indicating some relationship with transgene expression. In addition, body weight in adult mice was negatively correlated to plasma concentrations of IGFBP-1 (r = 0.7, P < 0.0001). Reproductive function also appeared to be severely affected, especially in homozygous females: mating that failed to result in pregnancy in half of the homozygous females crossed with nontransgenic males, suggestive of impaired fertilization or implantation; interrupted or prolonged pregnancies with fetal and neonatal death. Litter size was reduced in transgenic females (by about half in homozygotes) and in nontransgenic females mated with homozygous males, resulting from pre- or neonatal mortality. Moreover, deaths occurred within the first 5 days of life, with an incidence of approximately 50% in the litters of homozygous females, 12-18% among heterozygotes mated with nontransgenic or heterozygous males, respectively, and 30% among those mated with homozygous males. These results, suggesting that fetal transgene expression largely accounted for ante- and perinatal mortality, were confirmed by the predominance of homozygotes among those that could be analyzed genetically. Similarly impaired reproductive function was seen in line 124, but to a lesser degree. Although the mechanisms responsible for these disorders remain to be determined, our results indicate that permanent and uncontrolled hepatic expression of IGFBP-1, even at low levels, affects fertility in females and both ante- and postnatal development.

Animals↗
PubMed1996

Chronic electrical stimulation of the ventralis intermedius nucleus of the thalamus as a treatment of movement disorders.

Tremor was suppressed by test stimulation of the thalamic ventralis intermedius (VIM) nucleus at high frequency (130 Hz) during stereotaxy in nonanesthetized patients suffering from Parkinson's disease or essential tremor. Ventralis intermedius stimulation has since been used by the authors over the last 8 years as a treatment in 117 patients with movement disorders (80 cases of Parkinson's disease, 20 cases of essential tremor, and 17 cases of various dyskinesias and dystonias including four multiple sclerosis). Chronic electrodes were stereotactically implanted in the VIM and connected to a programmable stimulator. Results depend on the indication. In Parkinson's disease patients, tremor, but not bradykinesia and rigidity, was selectively suppressed for as long as 8 years. Administration of L-Dopa was decreased by more than 30% in 40 Parkinson's disease patients. In essential tremor patients, results were satisfactory but deteriorated with time in 18.5% of cases, mainly for patients who presented an action component of their but deteriorated with time in 18.5% of cases, mainly for patients who presented an action component of their tremor. In other types of dyskinesias (except multiple sclerosis), results were much less favorable. Fifty-nine patients underwent bilateral implantation and 14 other patients received implantation contralateral to a previous thalamotomy. Thirty-seven patients (31.6%) experienced minor side effects, which were always well tolerated and immediately reversible. Three secondary scalp infections led to temporary removal of the implanted material. There was no permanent morbidity. This tremor suppression effect could be due to the inhibition or jamming of a retroactive loop. Chronic VIM stimulation, which is reversible, adaptable, and well tolerated even by patients undergoing bilateral surgery (74 of 117 patients) and by elderly patients, should replace thalamotomy in the regular surgical treatment of parkinsonian and essential tremors.

Electric Stimulation Therapy↗
PubMed1995

Chordomas and chondrosarcomas of the cranial base: results and follow-up of 60 patients.

The management of chordomas and chondrosarcomas involving the cranial base remains controversial. The options for therapy include biopsy, partial resection, radical resection, and various forms of radiotherapy. In this article, we analyze the outcome of 60 patients with cranial base chordoma or chondrosarcoma treated with extensive surgical resection between 1984 and 1993. Forty-six patients had chordomas, and 14 had low-grade chondrosarcomas; 50% of these patients had been treated previously. Preoperative studies included computed tomography, magnetic resonance imaging, cerebral angiography, and balloon occlusion test of the internal carotid artery, as indicated. Magnetic resonance imaging was performed on all patients during follow-up. The surgical approaches used for tumor resection were predominantly the following: subtemporal, transzygomatic, transcavernous, and transpetrous apex; subtemporal and infratemporal; extended frontal; and extreme lateral transcondylar. Staged operations with a combination of approaches were used when necessary (52% of cases) to remove a tumor more completely. Statistical analysis was done by the chi 2 test and correlation matrix. Sixty-seven percent of the patients had total or near-total resection. Twenty percent of the patients received postoperative radiotherapy. Eleven patients died during the postoperative follow-up period, nine with chordomas and two with chondrosarcomas. Three patients died because of systemic complications within 3 months after surgery, five died because of tumor recurrence, one died from unrelated causes, and two died from late complications of radiotherapy. The recurrence-free survival rate for all tumors was 80% at 3 years and 76% at 5 years. Chondrosarcomas had a better prognosis than chordomas (recurrence-free survival rates, 90% at 5 years and 65% at 5 years, respectively; P = 0.09). Patients who had undergone previous surgery had a greater risk of recurrence (5-year recurrence-free survival rate, 64%) than did patients who had not undergone previous surgery (5-year recurrence-free survival rate, 93%; P < 0.05). Patients with total or near-total resection had a better 5-year recurrence-free survival rate (84%) than did patients with partial or subtotal resection (64%) (P < 0.05). Postoperative leakage of cerebrospinal fluid was the most frequent complication (30% of patients) and was found to increase the risk of permanent disability. Patients who had undergone previous radiotherapy had a greater risk of death in the postoperative period (within 3 months of their operations) and during follow-up. However, total or near-total resection did not increase the rate of postoperative disability.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1993

Chronic VIM thalamic stimulation in Parkinson's disease, essential tremor and extra-pyramidal dyskinesias.

Stereotactic thalamotomy of the VIM (ventral intermediate) nucleus is considered as the best neurosurgical treatment for Parkinsonian and essential tremors. However, this surgery, especially when bilateral, still presents a risk of recurrence and neurological complications. We observed that acute VIM stimulation at frequencies higher than 60 Hz during the mapping phase of the target suppressed the tremor of Parkinson's disease (PD) and essential tremor (ET). This effect was immediately reversible at the end of the stimulation. This was initially proposed as an additional treatment for patients already thalamotomized on the contralateral side, and then extended as a regular procedure for extra-pyramidal dyskinesias. Since January 1987, we implanted 126 thalami in 87 patients (61 PD, 13 ET, 13 dyskinesias of various origins). Deep brain stimulation electrodes were stereotactically implanted under local anaesthesia, using stimulation and micro-recording to delineate the best site of stimulation. Electrodes were subsequently connected to implantable programmable stimulators. The optimal frequency was around 130 to 185 Hz. The results (evaluated by a neurologist from 0 = no effect to 4 = perfect relief) are related to the type of tremor. Altogether, 71% of the 80 patients benefited from the procedure with grade 3 and 4 results. In 88% of the PD cases, the results were good (grade 3) or excellent (grade 4) and stable with time. Rigidity was moderately for a long improved but akinesia was not. The same level of improvement was observed in 68% of the ET patients and only in 18% of the other types of dyskinesias.(ABSTRACT TRUNCATED AT 250 WORDS)

Basal Ganglia Diseases↗
PubMed1992

Identification of an epidemic strain of Acinetobacter baumannii using electrophoretic typing methods.

Nosocomial infections due to Acinetobacter baumannii dramatically increased in a Lebanese medical center following an outbreak of hostilities in Lebanon in 1984. The incidence of infection caused by this organism has remained high in this institution, thus requiring the implementation of a strain typing system to aid in infection control. Three methods were investigated for their utility in differentiating among a representative group of 36 nosocomial Acinetobacter baumannii isolates obtained over a 10 month period from specimens of hospitalized patients. Isolates were typed by antibiogram analyses, plasmid fingerprinting, and total cell protein profiles. Only three distinct total cell protein profiles were detected, with one pattern accounting for 26 (72.2%) of the isolates. However, eight different plasmid profiles were observed, with 20 (55.5%) isolates having the same profile. Eleven distinct antibiograms were seen with the most prevalent pattern occurring in 21 isolates. Twenty of the 21 (95%) isolates with the common antibiogram also had the same plasmid profile and total protein profile (44.4% of total isolates). The combination of these three typing methods was useful in tracing the spread of these organisms in the medical center. The data obtained suggest the distribution of a common strain among at least six wards of this hospital.

Acinetobacter↗
PubMed1992

Outpatient management vs in-hospital management of children with new-onset diabetes.

The long-term results of outpatient management of subjects with newly diagnosed insulin-dependent diabetes mellitus (IDDM) are unknown. The longest follow-up described to date is for only one year, a time when most children with IDDM still make endogenous insulin. In this study, 41 young subjects with IDDM, treated and educated in the outpatient setting (1980 to 1984), were compared to a group of 80 similar subjects who received their initial education as hospital inpatients. Long-term glycemic control, as measured by longitudinal glycohemoglobin (HbA1) values was not different in the two groups (p greater than .05). We conclude that outpatient education and management of newly diagnosed subjects with IDDM is as safe and effective as inpatient treatment.

Adolescent↗
PubMed1991

What makes Susie cry? A symptom-context study of family therapy.

The aim of this investigation was to examine the context of recurrent crying episodes during family therapy sessions. We tested the relative contribution of social versus individual intrapsychic variables within a 10-session, videotaped, structural family therapy. Segments of therapy before crying episodes when compared with control (non-crying) segments were found to have higher levels of the following variables: involvement with others in the room, rejection, and concern about supplies. Two family variables were also higher before crying episodes: family discussion about patient, and patient receives hostility. A stepwise discriminant function analysis using these variables indicated that family discussion about the patient was most important in signaling onset of crying. The results are discussed in terms of individual and family theories of symptom formation as illuminated through this case study.

Adolescent↗
PubMed1990

Epidemic bacteremia due to Acinetobacter baumannii in five intensive care units.

From March 5, 1986 to September 4, 1987, Acinetobacter baumannii (AB) was isolated from blood or vascular catheter-tip cultures of 75 patients in five intensive care units at a hospital in New Jersey. To identify risk factors for AB bacteremia in the intensive care units, a case-control study was conducted. Characteristics of 72 case-patients were compared with those of 37 controls. Case-patients were more likely than controls to have had peripheral arterial catheters (odds ratio (OR) = 7.0, p less than 0.001), mechanical ventilation (OR = 5.8, p less than 0.001), hyperalimentation (OR = 5.7, p less than 0.001), or pulmonary arterial catheters (OR = 3.9, p less than 0.001). Arterial catheters were used with reusable pressure transducers for intravascular pressure monitoring. A logistic regression analysis identified four independent risk factors: transducers, ventilation, hyperalimentation, and days of transducer use at an insertion site. The strongest influence on the risk of AB bacteremia was exerted by number of days of transducer usage. Cultures of 70 transducer diaphragms or domes, 42 in-use and 28 in-storage, were positive for AB in 21% and 46%, respectively. Plasmid analysis showed that patient blood cultures and transducer isolates were identical. Transducers were wiped with alcohol in the units between patient uses. Since reusable transducers appeared to be the source of this outbreak, it is recommended that reusable transducers receive either high level disinfection or sterilization between patient uses.

Acinetobacter↗
PubMed1990

Patterns and mechanisms of beta-lactam resistance among isolates of Escherichia coli from hospitals in the United States.

To study the national distribution of beta-lactam resistance patterns and mechanisms among Escherichia coli organisms isolated in U.S. hospitals, 652 ampicillin-resistant (Am(r)) or ampicillin-intermediate (Ami) isolates were submitted to the Centers for Disease Control from March 1983 through July 1984 by nine hospitals participating in the National Nosocomial Infections Study. Among the isolates (most of which caused urinary tract infections), 78% were Am(r) and 22% were Ami by the interpretative criteria established by the National Committee for Clinical Laboratory Standards. Resistance to carboxypenicillins ranged from 73 to 74%, and that to acylureidopenicillins ranged from 43 to 66%. A total of 26% of the isolates were resistant to cephalothin, and 4% were resistant to cefazolin. Resistance to cefoxitin was 1%, while resistances to cefuroxime and cefamandole were 2 and 7%, respectively. With the exception of cefsulodin (98% resistant) and cefoperazone (1% resistant), there was no resistance to newer cephalosporins or aztreonam. In general, only minor differences in the incidence of resistance to beta-lactam antibiotics were noted in hospital-acquired versus non-hospital-acquired isolates as well as among isolates from various regions of the United States. TEM beta-lactamases were produced by 87% of the 237 Am(r) isolates examined. By our methods, OXA and chromosomal (type I) beta-lactamases were detected in 2 and 28 isolates, respectively, and plasmid-mediated extended-spectrum cephalosporinases were detected in none of the isolates. Disk substrate and clavulanic acid inhibition assays revealed that TEM beta-lactamase conferred Am(r) and resistance to carboxypenicillins, acylureidopenicillins, cephalothin, cefamandole, cefsulodin, and cefoperazone. A total of 391 isolates were screened for plasmids, and 259 isolates were examined by DNA hybridization with a TEM probe. Among 462 plasmids probed, 129 plasmids, ranging from 4 to 140 megadaltons, harbored TEM sequences. Although beta-lactam resistance in clinical isolates of E. coli is predominantly mediated by TEM beta-lactamase, the diverse spectrum of resistance appears to be related to additional strain=dependent factors.

Ampicillin↗