Biomedical subjects

T Holmes

Publications and source records attributed to T Holmes.

23 records · Page 2Linked to original sources

PubMed1975

Effectiveness of achievable urinary concentrations of tetracyclines against "tetracycline-resistant" pathogenic bacteria.

Hospitalized patients with urinary tract infections caused by Pseudomonas aeruginosa or other bacterial pathogens are frequently treated with parenteral antibiotics such as gentamicin. Many of these organisms are shown by Kirby-Bauer disk sensitivity testing to be resistant to tetracycline. One hundred seventy-one such tetracycline-resistant bacterial isolates were studied; 84% were found to be sensitive to achievable urinary concentrations of tetracycline. Two patients with long-standing chronic urinary tract infection with Pseudomonas were treated with tetracycline for a year and a half with excellent results. In a pilot clinical trial, eight of 12 hospitalized patients with urinary tract infection were treated successfully with tetracycline without regard to disk sensitivity data. Institution of tetracycline as soon as the microscopic diagnosis of urinary tract infection is made might be an acceptable empiric approach to the treatment of urinary infection in hospitalized patients who do not show evidence of sepsis.

Bacteriuria↗

PubMedDate not supplied

Tomotherapy: a new concept for the delivery of dynamic conformal radiotherapy.

Tomotherapy, literally "slice therapy," is a proposal for the delivery of radiation therapy with intensity-modulated strips of radiation. The proposed method employs a linear accelerator, or another radiation-emitting device, which would be mounted on a ring gantry like a CT scanner. The patient would move through the bore of the gantry simultaneously with gantry rotation. The intensity modulation would be performed by temporally modulated multiple independent leaves that open and close across the slit opening. At any given time, any leaf would be (1) closed, covering a portion of the slit, (2) open, allowing radiation through, or (3) changing between these states. This method would result in the delivery of highly conformal radiation. Overall treatment times should be comparable with contemporary treatment delivery times. The ring gantry would make it convenient to mount a narrow multisegmented megavoltage detector system for beam verification and a CT scanner on the treatment unit. Such a treatment unit could become a powerful tool for treatment planning, conformal treatment, and verification using tomographic images. The physical properties of this treatment delivery are evaluated and the fundamental design specifications are justified.

Humans↗

PubMedDate not supplied

Cutaneous-evoked tinnitus. I. Phenomenology, psychophysics and functional imaging.

DC00166e and acute unilateral deafferentation of the auditory periphery (auditory and vestibular afferents) can induce changes in the central nervous system that may result in unique forms of tinnitus. These tinnitus perceptions can be controlled (turned on and off) or modulated (changed in pitch or loudness) by performing certain overt behaviors in other sensory/motor systems. Clinical reports from our laboratory and several other independent sources indicate that static change in eye gaze, from a neutral head-referenced position, is one such behavior that can evoke, modulate and/or suppress these phantom auditory events. This report deals with a new clinical entity and a form of tinnitus that can be evoked directly by cutaneous stimulation of the upper hand and fingertip regions. In 2 adults, cutaneous-evoked tinnitus was reported following neurosurgery for space-occupying lesions at the base of the skull and posterior craniofossa, where hearing and vestibular functions were lost completely and acutely in one ear (unilateral deafferentation) and facial nerve paralysis (unilateral deefferentation) was present either immediately following neurosurgery or had occurred as a delayed-onset event. Herein, we focus on the phenomenology of this discovery, provide perceptual correlates using contemporary psychophysical methods and document in one individual cutaneous-evoked tinnitus-related neural activity using functional magnetic resonance imaging. In a companion paper, neuroanatomical and physiological interactions between auditory and somatosensory systems, possible mechanistic accounts and relevant functional neuroimaging studies are reviewed.

Aged↗

PubMedDate not supplied

Cutaneous-evoked tinnitus. II. Review Of neuroanatomical, physiological and functional imaging studies.

Cutaneous-evoked tinnitus is a clinical entity that has not been reported previously in the neurootological literature. Herein, a neuroscience framework that encompasses several distinct areas of research is used to conceptualize and help understand this phenomenon. We review normal neuroanatomical and physiological interactions between auditory and somatosensory systems in mammals. Also considered are mechanistic accounts of lesion-induced changes in the CNS following deafferentation/deefferentation of peripheral sensory or motor structures that may have a relationship to this phenomenon, as well as the role of functional imaging modalities in studying various phantom perceptions.

Brain↗

PubMedDate not supplied

Nitrate contamination of domestic potable water supplies: a social problem?

Nitrate contamination of potable water supplies is a recognized health hazard. Potentially, the contamination of private drinking water supplies could be a problem in the rural Palouse area of Idaho and Washington. Studies have shown that 12 percent of the rural population of Whitman County, Washington, may be drinking water containing nitrates in excess of the national standard. Yet there is no organized concern about this potential health hazard among local citizens. After reviewing the literature on nitrate contamination of ground water and discussing nitrate contamination of private potable water supplies in the Palouse, we use a social movement theory of social problems to explain why this situation has not been defined as a public health problem.

Humans↗