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W Eisner

Publications and source records attributed to W Eisner.

34 records · Page 2Linked to original sources
PubMed1995

Tracing the spread of methicillin-resistant Staphylococcus aureus by Southern blot hybridization using gene-specific probes of mec and Tn554.

In a community hospital in Brooklyn, New York, over a 3-year period, 79 methicillin-resistant Staphylococcus aureus (MRSA) isolates from five different case clusters were subtyped by Southern blot hybridization with two previously characterized gene probes, mec and Tn554. Together, the genotyping enabled the hospital infection control team to differentiate simultaneous MRSA clusters in the surgical intensive care unit (type I:A) and the open heart unit (type II:J), document the spread of one strain (type I:A) between roommates, identify an endemic strain (type II:J) from cardiac monitors and medical personnel, and identify an unrelated outbreak strain (type II:NH) in the labor and delivery unit. On the basis of this investigation it is clear that the routine DNA fingerprinting of MRSA in health care facilities, to monitor their spread and identify cases of nosocomial infections, is an important infection control measure.

Blotting, Southern↗
PubMed1995

The mapping and continuous monitoring of the intrinsic motor nuclei during brain stem surgery.

A comprehensive technique was developed for continuous electrophysiological monitoring of intrinsic brain stem motor function during surgery to remove space-occupying lesions in the fourth ventricle and brain stem. The technique is analogous to that used during surgery in the cerebellopontine angle; motor nuclei and peripheral pontine fiber tracts of Cranial Nerves III-XII are identified by the electrical stimulation of structures in the operative field and the evaluation of the compound muscle action potentials recorded from the corresponding muscles of the head. Nerve function is monitored continuously by recording the ongoing electromyographic activity in these same muscles. Broadcasting electromyographic responses through a loudspeaker gives the surgeon immediate feedback on the status of the motor nuclei being monitored. Advantages of this technique include 1) the positive, objective identification of the nuclei and fiber tracts; 2) the continuous feedback on the status of these structures; 3) a safe approach through the fourth ventricle to the lesions in the brain stem; 4) the positive identification of the boundaries between the neoplasm and the motor structures of the rhomboid fossa; and 5) a warning to the surgeon of potentially harmful nerve manipulations (contact, dissection, transection) during surgery. After this technique was used in 16 consecutive operations to remove cavernomas (n = 9), gliomas (n = 4), and other types of tumors (n = 3), surgical and neurological results showed the method to be reliable and simple to perform.

Adult↗
PubMed1995

Contrast-dependent responses in the human visual system: childhood through adulthood.

Visual evoked potentials (VEPs) to temporal modulation of spatial patterns, recorded from humans ranging in age from 4-42 years, demonstrated that contrast-dependent responses exist in early childhood and change dramatically throughout childhood. Bright or dark isolated-check stimuli were used to emphasize contributions from ON or OFF pathways to the VEP. (ON and OFF pathways constitute one major pair of parallel subsystems, which process brightness [positive-contrast] and darkness [negative-contrast] information, respectively.) The developmental effects observed for each pathway were similar in magnitude and time course, suggesting maturation of a common physiological mechanism dependent on spatial contrast. Children's responses were more variable and larger than those of adults, and exhibited a relative phase lag. In addition, we recorded transient VEPs to a conventional contrast-reversing checkerboard pattern. The latency of the major positive wave (P100) was found to decrease, while the latency of the initial positive wave (P60) was found to increase, with increasing age. We propose a vector-summation model, which posits a relative decrease in cortical excitation with increasing age, to explain our major findings.

Adolescent↗
PubMed1995

[Function-controlled neurosurgery. Neurophysiologic and neuropsychological monitoring during surgery of the nervous system].

Neuromonitoring of neural structures has become increasingly common during surgery near cortical areas representing sensorimotor and language function (epilepsia, tumors), in the brain stem and the spinal cord (tumors), near cranial nerves (cerebellopontine angle tumors, trigeminal neuralgia, hemifacial spasm), and in the cauda equina (tumors, tethered spinal cord). The technical spectrum to monitor these operations includes electrical cortical stimulation to evoke sensorimotor phenomena and language disturbances, electroneurography and -myography of the cauda equina, motor cranial nerves and nuclei, and somatosensory, motor and acoustic evoked potentials. The goals of intraoperative neuromonitoring are: (1) minimizing the risk of suffering neurological and neuropsychological injury as a result of surgery; (2) extending the surgical spectrum to lesions that have previously been considered inoperable or hazardous to operate upon; (3) intraoperative electrophysiological documentation that the goal of surgery has been achieved; (4) intraoperative basic research.

Brain↗
PubMed1995

[The motor hand area. Noninvasive detection with functional MRI and surgical validation with cortical stimulation].

In this study, activation of cortical sites by specific motor tasks (opening and closing of the hand) was examined by fMRI utilizing the blood-oxygen-level-dependent (BOLD) technique. fMRI was employed in five volunteers and in six patients with tumors in the vicinity of the central region. In the patients, the fMRI data and intraoperative cortical mapping were compared. Our results indicate good correlation of these two methods and that there are no significant differences in the localization of the motor hand area.

Adult↗
PubMed1994

Clinical and molecular epidemiology of acinetobacter infections sensitive only to polymyxin B and sulbactam.

A nosocomial outbreak of infections due to imipenem-resistant Acinetobacter baumannii occurred in a New York hospital after increased use of imipenem for cephalosporin-resistant klebsiella infections. We identified all A baumannii isolates over 12 months, reviewed corresponding patient records, and compared strains with different antibiotic susceptibility patterns by restriction endonuclease analysis. Environmental surveillance cultures were done before and after institution of control measures. 59 patients harboured imipenem-resistant A baumannii, and 18 were infected. Isolates from patients were resistant to all routinely tested antibiotics, including imipenem. Further studies showed susceptibility to polymyxin B and sulbactam. These isolates were identical by restriction endonuclease analysis to A baumannii isolates susceptible to imipenem alone, or to imipenem and amikacin, but differed from broadly susceptible isolates. Surveillance cultures showed hand and environmental colonisation by imipenem-resistant strains. Infection and colonisation were eliminated by intensive infection control measures, and irrigation of wounds with polymyxin B. Increased use of imipenem against cephalosporin-resistant klebsiella may lead to imipenem resistance among other species, particularly acinetobacter. Such resistance appears to derive from a prior multi-resistant clone, in contrast to one which retains susceptibility to several antibiotics.

Acinetobacter↗
PubMed1994

Creative coping: a cognitive-behavioral group for borderline personality disorder.

Patients with borderline personality disorder (BPD) pose major therapeutic challenges to mental health professionals. Effective and practical treatment of the patient with BPD is needed in short-term inpatient settings, and psychiatric nurses are in a unique position to implement innovative treatment strategies for the borderline patient. The Creative Coping Group is a practice model designed by psychiatric nurses for patients with BPD, using a cognitive-behavioral framework. It is a group therapy intervention based on Linehan's Dialectical Behavior Therapy (DBT) that addresses the ineffective coping of patients with BPD that results in chronic suicidal behavior. Linehan's framework focuses on deficits in emotional control, interpersonal effectiveness, and distress tolerance. The objective of the group sessions is to foster insight and awareness into symptoms, feelings, and behaviors through psychoeducation, group exercises, discussion, and homework assignments.

Adaptation, Psychological↗
PubMed1994

Intraoperative motor and sensory monitoring of the cauda equina.

A set of standard techniques to monitor the motor and sensory function of the cauda equina is proposed for surgery in the lumbosacral spinal canal for the release of a tethered cord or the removal of a neoplasm. Continuous loudspeaker-controlled recording of electromyographic activity in four leg muscles of both sides supplied the surgeon with immediate feedback on injury to any of the motor roots from the second lumbar to the fourth sacral segment. Continuous recording of tibial nerve somatosensory evoked potentials yielded information about the functional state of parts of the lumbosacral sensory pathways. Motor roots could be identified by electrical stimulation in the operating field with bipolar stimulation forceps and recording of compound muscle action potentials from the leg muscles. Sensory nerve roots could be identified by nerve root somatosensory evoked potentials recorded from the scalp after the electrical stimulation of the exposed nerve. This set-up is a combination of previously developed monitoring techniques and provides the surgeon with functional information: 1) continuous feedback on the state of the endangered motor and sensory function of the cauda equina; and 2) rapid anatomical identification of nerve roots and their distinction from fibrous or neoplastic structures.

Adolescent↗
PubMed1993

Emergence of vancomycin-resistant enterococci in New York City.

Enterococci, a common cause of nosocomial infection, are intrinsically resistant to most antimicrobials and readily acquire additional resistance. Vancomycin-resistant enterococci (VRE) have caused clusters of nosocomial infections since 1988. In April, 1991, the New York City Department of Health asked all city laboratories to submit suspected VRE isolates for confirmation. Clinical and epidemiological characteristics of the first 100 patients with VRE were identified, and antimicrobial susceptibility testing, restriction enzyme analysis, and DNA-DNA hybridisation with the vanA gene probe were done. From September, 1989, to October, 1991, 361 patients with VRE were identified at 38 hospitals. The number of hospitals reporting VRE increased from 1 in 1989 to 38 by October, 1991. 98% of 100 VRE infections were nosocomially acquired and 83% patients had received vancomycin and/or a cephalosporin in the 30 days before isolation of VRE. Of 23 isolates from 21 of the first 100 patients, 19 (83%) were resistant to all available antimicrobials. Four vanA probing patterns were noted, and restriction enzyme analysis of the 23 isolates revealed 14 strains. VRE have emerged rapidly in New York City. Molecular analyses suggest that a highly mobile genetic element--eg, a transposon--is responsible for the rapid spread of vancomycin resistance.

Aged↗
PubMed1993

Evidence for a clonal origin of methicillin resistance in Staphylococcus aureus.

Soon after methicillin was introduced into clinical practice in the early 1960s, resistant strains of Staphylococcus aureus (MRSA) appeared, bearing a newly acquired resistance gene, mecA, that encodes a penicillin binding protein, PBP2a. MRSA have spread throughout the world, and an investigation of the clonality of 472 isolates by DNA hybridization was performed. All 472 isolates could be divided into six temporally ordered mecA hybridization patterns, and three of these were subdivided by the chromomosomal transposon Tn554. Each Tn554 pattern occurred in association with one and only one mecA pattern, suggesting that mecA divergence preceded the acquisition of Tn554 in all cases and therefore that mecA may have been acquired just once by S. aureus.

Bacterial Proteins↗
PubMed1992

Nucleotide sequences and biologic properties of toxic shock syndrome toxin 1 from ovine- and bovine-associated Staphylococcus aureus.

Toxic shock syndrome toxin (TSST) 1 was purified from ovine (TSST-ovine) and bovine (TSST-bovine) mastitis-associated Staphylococcus aureus. These toxins were previously reported to have molecular weights identical to that of human TSST-1. However, TSST-ovine was reported as having an isoelectric point (pI) of 8.5, whereas TSST-bovine has the same pI (7.2) as TSST-1. Nucleotide sequence analysis revealed that TSST-bovine was identical to TSST-1 and that TSST-ovine had 14 nucleotide differences that changed 9 amino acid residues. Only 1 nucleotide difference, at position 514, was predicted to cause an amino acid charge difference, as glutamic acid at position 132 of TSST-1 was changed to lysine in TSST-ovine. Like TSST-1, TSST-ovine was mitogenic, but unlike TSST-1, it was not pyrogenic, was unable to enhance endotoxic shock, and was unable to induce TSS in a rabbit model. Also, TSST-ovine was less reactive to certain monoclonal antibodies raised against TSST-1.

Amino Acid Sequence↗
PubMed1992

Multiple methicillin-resistant Staphylococcus aureus strains as a cause for a single outbreak of severe disease in hospitalized neonates.

Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of nosocomial infection. Outbreaks of infection caused by these pathogens are generally considered to be traceable to introduction of single strains into a hospital population. A large outbreak of bacteremic disease that recently occurred in our neonatal intensive care unit (11 episodes in 10 patients) involved 9 low birth weight infants and was associated with serious infection (4 episodes of meningitis). To determine the role of a single point source in this outbreak, isolates were characterized based on phenotypic and genotypic analyses. Phenotypic analysis included assessing hemolytic activity, phage typing, antimicrobial susceptibility testing and methicillin resistance population analysis. Genotypic analysis included assessment of plasmid profiles, dot-blot hybridization, restriction enzyme fragment pattern analysis and hybridization analysis of chromosomal DNA using a panel of staphylococcal gene probes. This analysis established that at least two distinct strains of MRSA were responsible for disease during this outbreak. This experience demonstrates the potential for MRSA to cause severe disease in the neonatal intensive care unit and indicates that the epidemiology of MRSA outbreaks is more complex than the spread of a single strain of bacteria.

Cross Infection↗
PubMed1991

Role of external bacterial flora in the pathogenesis of acute postoperative endophthalmitis.

The source of infecting bacteria is often unknown in postoperative endophthalmitis. Using techniques of molecular epidemiology, the authors demonstrate that an organism isolated from the vitreous was genetically indistinguishable from an isolate recovered from the patient's eyelid, conjunctiva, or nose in 14 (82%) of 17 cases of endophthalmitis. In two cases of Staphylococcus epidermidis endophthalmitis, after cataract surgery was performed by the same surgeon on the same day, genetic analysis demonstrated that the infecting organisms from the two patients' vitreous were distinct, and, furthermore, that in each case the external isolates were indistinguishable from the vitreous isolate. The results implicate the patients' external tissues as the source of the infecting organism in those cases of acute postoperative endophthalmitis studied. Therefore, attention should be directed toward the external tissues and their microbial flora in the prophylaxis and prevention of postoperative bacterial endophthalmitis.

Aged↗
PubMed1987

The molybdenum-pterin binding protein is encoded by a multigene family in Clostridium pasteurianum.

There are three variants of the molybdenum-pterin binding protein (Mop) encoded by three distinct genes in Clostridium pasteurianum. Nucleotide sequence analysis shows that the three mop genes have greater than 90% homology at the nucleotide level. Upstream from the coding region of each mop gene are potential promoter consensus sequences. Analysis of Mop purified from cells grown under nitrogen-fixing conditions indicates all three genes are expressed. Sequence analysis of the three mop genes and the gene products predicts that there are 10 amino acid replacements among the family. The amino acid replacements are chemically conservative accounting for the co-purification of the three variants of Mop. Protein chemistry data suggest the possibility that glutamic acid residues in Mop may be modified in vivo.

Amino Acid Sequence↗