Using motion capture technology to measure the effects of magnification loupes on dental operator posture: A pilot study.

BACKGROUND: Motion analysis has great potential for quantitatively evaluating dental operator posture and the impact of interventions such as magnification loupes on posture and subsequent development of musculoskeletal disorders. OBJECTIVE: This study sought to determine the feasibility of motion capture technology for measurement of dental operator posture and examine the impact that different styles of magnification loupes had on dental operator posture. METHODS: Forward and lateral head flexion were measured for two different operators while completing a periodontal probing procedure. Each was measured while wearing magnification loupes (flip up-FL and through the lens-TTL) and basic safety lenses. RESULTS: Operators both exhibited reduced forward flexion range of motion (ROM) when using loupes (TTL or FL) compared to a baseline lens (BL). In contrast to forward flexion, no consistent trends were observed for lateral flexion between subjects. CONCLUSIONS: The researchers can report that it is possible to measure dental operator posture using motion capture technology. More study is needed to determine which type of magnification loupes (FL or TTL) are superior in improving dental operator posture. Some evidence was found supporting that the quality of operator posture may more likely be related to the use of magnification loupes, rather than the specific type of lenses worn.

Randomized phase II trial of gemcitabine plus irinotecan or docetaxel in stage IIIB or stage IV NSCLC.

BACKGROUND: To evaluate the activity and tolerability of gemcitabine plus irinotecan or docetaxel as first-line chemotherapy for advanced non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Eligible patients with chemotherapy-naïve stage IIIB or IV NSCLC were randomized to receive gemcitabine 1000 mg/m2 on days 1 and 8, plus either irinotecan 100 mg/m2 or docetaxel 40 mg/m2 on days 1 and 8. Treatment was administered every 3 weeks. RESULTS: Of the 80 enrolled patients with stage IIIB or IV NSCLC, 78 were evaluable for activity and safety. Overall response rates, consisting of partial responses, were 12.8% [95% confidence interval (CI) 4% to 35%] for gemcitabine-irinotecan and 23.1% (95% CI 10% to 42%) for gemcitabine-docetaxel. Median overall survival was 7.95 months (95% CI 5.2-10.2) and 12.8 months (95% CI 7.9-17.1) for gemcitabine-irinotecan and gemcitabine-docetaxel, respectively. The corresponding estimated 1-year survivals were 23% and 51%, respectively. The 2-year survival rate in arm A (gemcitabine-irinotecan) is not currently estimable. The 2-year survival rate for arm B (gemcitabine-docetaxel) is 22% (95% CI 6% to 37%). Both combinations were well tolerated; the most common hematological toxicity was neutropenia, which occurred in 26% of patients in each treatment arm. CONCLUSIONS: These results suggest that gemcitabine plus docetaxel or irinotecan is well tolerated in patients with chemotherapy-naïve advanced NSCLC. The survival data with the combination gemcitabine-docetaxel are promising. Gemcitabine-docetaxel combination therapy may be particularly useful for patients who have experienced toxicities with a platinum regimen or in patients who may be more susceptible to platinum-related toxicity.

A simple automated solution for removing and applying sealing microplate lids.

With the improved reliability and efficiency of automation, there has been an increased desire to integrate automated sample management with automated screening systems. In order to store samples "on line" for an extended period of time, an automation-compatible means for sealing and unsealing microplates is necessary. Numerous commercial solutions are available for removing loose-fitting microplate lids; however, the task of removing a tight-fitting matted lid such as the RoboLid is more challenging. This paper discusses the design of an automated workstation for the application and removal of such tight-fitting microplate lids.

Quantitative aspects of the clinical performance of transverse tripolar spinal cord stimulation.

A multicenter study was initiated to evaluate the performance of the transverse tripolar system for spinal cord stimulation. Computer modeling had predicted steering of paresthesia with a dual channel stimulator to be the main benefit of the system. The quantitative analysis presented here includes the results of 484 tests in 30 patients. For each test, paresthesia coverage as a function of voltage levels was stored in a computerized database, including a body map which enabled calculation of the degree of paresthesia coverage of separate body areas, as well as the overlap with the painful areas. The results show that with the transverse tripolar system steering of the paresthesia is possible, although optimal steering requires proper placement of the electrode with respect to the spinal cord. Therefore, with this steering ability as well as a larger therapeutic stimulation window as compared to conventional systems, we expect an increase of the long-term efficacy of spinal cord stimulation. Moreover, in view of the stimulation-induced paresthesia patterns, the system allows selective stimulation of the medial dorsal columns.

Estimation of fiber diameters in the spinal dorsal columns from clinical data.

Lack of human morphometric data regarding the largest nerve fibers in the dorsal columns (DC's) of the spinal cord has lead to the estimation of the diameters of these fibers from clinical data retrieved from patients with a new spinal cord stimulation (SCS) system. These patients indicated the perception threshold of stimulation induced paresthesia in various body segments, while the stimulation amplitude was increased. The fiber diameters were calculated with a computer model, developed to calculate the effects of SCS on spinal nerve fibers. This computer model consists of two parts: 1) a three-dimensional (3-D) volume conductor model of a spinal cord segment in which the potential distribution due to electrical stimulation is calculated and 2) an electrical equivalent cable model of myelinated nerve fiber, which uses the calculated potential field to determine the threshold stimulus needed for activation. It is shown that the largest fibers in the medial DC's are significantly smaller than the largest fibers in the lateral parts. This finding is in accordance with the fiber distribution in cat, derived from the corresponding propagation velocities. Moreover, it is shown that the mediolateral increase in fiber diameter is mainly confined to the lateral parts of the DC's. Implementation of this mediolateral fiber diameter distribution of the DC's in the computer model enables the prediction of the recruitment order of dermatomal paresthesias following increasing electrical stimulation amplitude.

Clinical evaluation of paresthesia steering with a new system for spinal cord stimulation.

OBJECTIVE: The goal was to evaluate, in a clinical study, the predicted performance of the transverse tripolar system for spinal cord stimulation, particularly the steering of paresthesia, paresthesia coverage, and the therapeutic range of stimulation. METHODS: Six transverse tripolar electrodes were implanted in the lower thoracic region in four patients experiencing chronic neuropathic pain. Electrode positions, relative to the spinal cord, were estimated from computed tomographic scans. A dual-channel stimulator was used for initial percutaneous tests, and an implanted single-channel stimulator was used for follow-up test sessions. Nine "balance" settings and several cathode-anode combinations were used with the dual-channel and single-channel stimulator, respectively. In each test, the increase of paresthesia coverage from the perception threshold to the discomfort threshold was registered on a body map and the corresponding voltages were recorded. RESULTS: Paresthesia steering occurred in all but one patient. The normalized steering score, enabling quantitative comparisons of paresthesia steering among tests and patients, showed that maximum paresthesia steering occurred when the electrode was at least 3 mm dorsal to the spinal cord and centered <2 mm from its midline. Paresthesia coverage included 70 to 100% of the body up to the electrode level, unless the electrode migrated or had broken wires. The therapeutic range, defined as the discomfort/perception of paresthesia threshold ratio, varied from 1.6 to 4.0. CONCLUSION: The clinical performance of transverse tripolar stimulation is in accordance with the characteristics predicted by computer modeling. It enables finer control of paresthesia than that achieved by polarity changes in conventional spinal cord stimulation systems.

Biocarbon ureterostomy device for urinary diversion. Multicenter clinical trial.

The bioCarbon ureterostomy device is a stomal prosthesis for upper tract urinary diversion that has had preliminary successes in animal and human trials in Europe and Peru. Implantation of a pure carbon stomal prosthesis offers the potential advantages of high biocompatibility, lack of encrustation, and elimination of stomal stenosis which is frequently associated with cutaneous ureterostomy. Nine bioCarbon ureterostomy devices were implanted from August, 1984 through July, 1985. Although successful implantation was achieved in 2 patients, the complication rate was high. The bioCarbon ureterostomy device has potential as an alternative form of urinary diversion. However, significant problems need to be remedied before it can be recommended for routine clinical application.

Types and locations of respiratory-related neurons in lateral tegmental field of cat medulla oblongata.

Extracellular microelectrode recordings were made from a total of 868 neurons in the medullas of cats in regions known to contain high densities of respiratory-related neurons (solitary tract complex, nucleus ambiguus/retroambigualis, lateral tegmental field). Both the discharge patterns and the locations of units were noted and correlated with a recently described substructure of the tegmental field of the cat medulla in which neuronal cell bodies are found associated with sheets of blood vessels supplying the brainstem. The majority of cells were phasically firing (59%) with activity confined to either the inspiratory or the expiratory phase, 21% were tonically firing cells with no discernible respiratory modulation and 20% were silent neurons, responsive to electrical stimulation of the vagus nerves or the dorsolateral pons in the vicinity of nucleus parabrachialis, but not to various respiratory stimuli. Within the solitary tract complex inspiratory discharge patterns were predominant (94%), while in nucleus ambiguus/retroambigualis 26% of the neurons had expiratory patterns with the rest being inspiratory (68%) or tonic (6%). Within the lateral tegmental field, the percentages of inspiratory, expiratory and tonic patterns were 51, 9 and 40%. Thus, inspiratory type patterns were found throughout the medulla, but expiratory patterns were most common in the ambiguus/retroambigualis nuclei. Found within all 3 major regions, but primarily within the lateral tegmental field of the rostral medulla were neurons that discharged with a brief burst at the inspiratory to expiratory phase transition. These cells had properties consistent with the off-switch mechanism: extreme late-inspiratory onset of discharge with the onset time being delayed by lung inflation, peak discharge at or slightly after the peak activity of the diaphragmatic EMG and a discharge rate which was insensitive to lung inflation. Within the lateral tegmental field, where longitudinal sheets of blood vessels running radially with respect to the IVth ventricle have been described, it was found that 85% of the tonically active units and 93% of the respiratory modulated cells were located less than 200 microns from the planes of these sheets. In addition, 87% of the neurons that could be antidromically or synaptically activated from the dorsolateral rostral pons were similarly located.

An electrophysiological study of medullary neurons projecting to nucleus parabrachialis of the cat.

Neuronal activity was recorded from a total of 868 cells in the medulla of cats in regions known to project to nucleus parabrachialis (NPB) of the pons and thought to be involved in respiration. Of 196 neurons antidromically (85) or synaptically (111) activated from NPB, 178 were silent in the decerebrate or barbiturate-anesthetized preparation, and could not be induced to activity by increasing CO2, activating Breuer-Hering reflexes, stimulation of the vagus or vagotomy. We conclude that the direct pathway from the lateral tegmental field of the medulla to NPB is not significantly involved in respiratory function in these preparations.

The effects of noxious heat on responses of spinocervical units to low intensity cutaneous stimuli.

The responses of spinocervical neurons to sinusoidal hair displacements were studied during and in the absence of radiant heating of parts of the hindpaw to noxious levels (45-65 degrees C). Noxious heat usually increased background discharge and lowered the signal-to-noise ratio at low frequencies of hair displacement. At higher frequencies over 20 Hz, this ratio was slightly depressed for half of the cells, and dramatically increased for the others. Similar effects were found when the heating was off the receptive field for hair displacement, which suggests a central cause for these effects.

Combination therapy protocol for stage III or IV carcinoma of the oral cavity, oropharynx and hypopharynx.

Combined therapy programs have improved recurrent and nodal metastatic rates but have not controlled distant metastases. A pilot study undertaken at Ohio State University evaluated the feasibility of adding chemotherapy to a combined modality regimen. The first phase determined that the toxicity of a four-drug combination chemotherapy yielded a favorable risk/benefit ratio and justified its inclusion in a protocol for untreated cancers. The second phase evaluated chemotherapy followed by surgery and postoperative irradiaation for untreated Stage III and IV epidermoid carcinoma of the oral cavity, oropharynx or hypopharynx. The overall chemotherapy response rate is 88% (22/25) with 6 complete and 16 partial responses. Evaluation of pathology specimens revealed 7 of 14 primary sites and 4 of 15 neck specimens had no histologic evidence of carcinoma. In the 10 patients who received all 3 modalities, 9 are free of disease (6 to 17 mo. follow-up).

Topology of ascending brainstem projections to nucleus parabrachialis in the cat.

The afferent projections to nucleus parabrachialis (NPB) and nearby pontine areas from the lower brainstem were studied in cats using retrograde horseradish peoxidase (HRP) and anterograde autoradiographic tracing techniques. Two groups of medullary neurons send major projections to NPB and the Kölliker-Fuse nucleus (KF): 1) the solitary complex, especially the medial nucleus of the solitary tract (SM), nearby smaller cells of the dorsal motor nucleus of the vagus (DMV) and the commissural nucleus; and 2) the lateral tegmental field (FTL), or parvocellular reticular formation. Autoradiographic tracing from these areas demonstrated terminal fields in NPB/KF and emphasized a ventrolateral route to NPB from both sources, with axons ascending between the facial nerve and superior olive and passing rostral to the trigeminal nuclei. Minor projections to NBPB/KF originate in the ventrolateral nucleus of the solitary tract, area subpostrema, the alaminar spinal trigeminal nucleus, the gigantocellular and magnocellular tegmental fields, and an area dorsal to the ipsilateral inferior olive. Topographical features of the major projections were studied by correlating the locus of overlap of injection sites with the locations of HRP-positive cells. Medial areas of SM/DMV project mostly to medial parts of NPB, while lateral areas near the solitary tract project to lateral parts of NPB and KF. Crossing projections from SM/DMV favor dorsolateral NPB and KF. FTL neurons in dorsomedial areas project more to medial NPB, and ventrolateral areas project to lateral NPB/KF. Using a new coordinate system to locate and normalize the positions of FTL neurons, data from many brains were collated. FTL cells projecting to NPB/KF were found to be on discrete longitudinal sheets, running radially with respect to the fourth ventricle. This substructure and related evidence suggest a preferred pattern for neuroanatomical connections and information processing in the lateral reticular areas of the brainstem, and help in understanding the topography of the projections to NPB/KF.

Clinical toxic effects of 2,3-dihydro-1H-imidazo[1,2-b]pyrazole (IMPY) with relevant pharmacokinetic parameters.

2,3-Dihydro-1H-imidazo[1,2-b]pyrazole (IMPY) is an inhibitor of ribonucleotide reductase and of DNA synthesis selected for clinical trials because of its activity against L1210 leukemia variants resistant to other inhibitors of this enzyme. A phase I trial designated to allow in-depth pharmacologic evaluation has recently been completed and the clinical results and preliminary pharmacokinetic data are reported here. Each patient received IMPY by three different schedules. A single iv bolus, intermittent 5-day bolus, and 5-day continuous infusion were given at 3-week intervals. The major dose-limiting toxic effects were vomiting, rbc hemolysis, confusion, and somnolence. All toxic effects seemed to be dose- and schedule-dependent and were readily reversible. IMPY enters the cerebrospinal fluid and is highly concentrated in gastric secretions. Clearance of IMPY is impaired in the presence of hepatic insufficiency. Eighteen of 26 patients entered are evaluable for response, including one patient with colon cancer with minimal response and three patients with stable disease.

Hodgkin's disease occurring in a patient with the Wiskott-Aldrich syndrome.

Hodgkin's disease, nodular sclerosing, developed in a 16-year-old man with the Wiskott-Aldrich syndrome. Two brothers and two nephews had documented Wiskott-Aldrich syndrome and had died of infectious complications in childhood. While the patient reported here had lifelong thrombocytopenia and recurrent upper respiratory infections, he had no severe infection prior to the development of Hodgkin's disease. Skin test sensitization with dinitrochlorobenzene was unsuccessful. No antibodies were found after immunization with pneumococcal polysaccharides. Platelet aggregation studies were abnormal in the patient, his mother, and one of his nephews. A complete response of short duration occurred after treatment with nitrogen mustard, vincristine, procarbazine, and prednisone. On recurrence, he proved unresponsive to further chemotherapy or radiation therapy. Infection with four different fungi was found at autopsy. This patient is the third recorded case of Hodgkin's disease associated with the Wiskott-Aldrich syndrome.

Cis-dichlorodiammineplatinum(II), methotrexate, bleomycin, and vincristine in head and neck cancer: a pilot study.

Thirty-nine patients with advanced epidermoid carcinoma of the head and neck were treated with a combination of cis-dichlorodiammineplatinum(II), methotrexate, bleomycin, and vincristine. Twenty-nine patients were evaluable for response and 39 were evaluable for toxicity. With this regimen toxicity was acceptable and the following rates were observed in a total of 139 treatment courses: 100% (nausea and vomiting), 3% (decreased creatinine clearance), 4% (thrombocytopenia), 5% (leukopenia), and 2% (pulmonary fibrosis). There was one death due to sepsis during a period of chemotherapy-induced leukopenia. Although the patients treated with this regimen had advanced disease and had been treated aggressively previously, an overall response rate of 24% was observed, with three patients (10%) having a complete response. Median duration of response was 7 + months. These results indicate that this intensive combination chemotherapy has a sufficiently favorable risk/benefit ratio to allow its evaluation in randomized clinical trials in patients with head and neck cancer.

5 FU infusion with mitomycin-C vs. 5 FU infusion with methyl-CCNU in the treatment of advanced upper gastrointestinal cancer: a Southwest Oncology Group Study.

A randomized trial was conducted by the Southwest Oncology Group (SWOG) in advanced carcinoma of the stomach and pancreas. Patients were assigned to receive monthly 5-fluorouracil 96-hour continuous infusions with either bolus mitomycin-C or oral methyl-CCNU. Mitomycin-C and methyl-CCNU were administered every eight weeks. The 5 FU-mitomycin combination produced a 14% and 22% response rate in disseminated stomach and pancreatic carcinoma, respectively. The combination of infusion 5 FU and methyl-CCNU achieved responses in 9% and 5% of stomach and pancreatic tumors, respectively. There was no significant difference in survival between limbs for either tumor. Median survival in gastric carcinoma on the 5 FU-mitomycin regimen was 25 weeks vs. 18 weeks on the 5 FU-METHYL-CCNU arm. In pancreatic carcinoma median survival on the mitomycin limb was 19 weeks as compared to 17 weeks on the methyl-CCNU program. Leukopenia was greater for the first course on the mitomycin limb. Regression analysis demonstrated that performance status was the most important pretreatment characteristic for predicting survival in both tumors. Neither 5 FU infusion combination appears to significantly alter the dismal prognosis of advanced upper gastrointestinal neoplasms.

Neoantigen response in patients successfully treated for lymphoma. A Southwest Oncology Group study.

To ascertain the cellular immune function of patients successfully treated for lymphoma, we measured skin-test reactivity to a battery of recall antigens, phytohemmagglutinin (PHA), and the neoantigens keyhole limpet hemocyanin (KLH) and dinitrochlorobenzene (DNCB). Seventy-four patients with Hodgkin's disease and 31 patients with non-Hodgkin's lymphoma were studied from 3 to 186 months after cessation of therapy for lymphoma. Although reactivity to recall antigens and PHA was normal, the number of patients responding to the neoantigens was significantly (P less than 0.01) lower than normal (KLH, 35%; and DNCB, 34%). This impairment in reactivity to neoantigens could not be correlated with specific diagnosis, stage of disease, or type of treatment. Reactivity to DNCB was significantly (P less than 0.01) improved in those patients studied more than 3 years after treatment, but the number who reacted was still markedly abnormal (17 of 33). Thus, successfully treated patients with lymphoma seem to have difficulty in responding to new foreign antigens.

Normal human monocytes inhibit tumor cell growth in vitro.

Normal human monocytes were evaluated in an in vitro assay of growth inhibition of tumor cells. Monocytes were isolated from the blood of 6 normal subjects by Ficoll-Hypaque separation and adherence to plastic microtest wells. Cervical carcinoma cells (HeLa) were added to the microwells to result in a ratio of 50 monocytes to one HeLa cell. Cultures were then incubated for 6 to 46 hr. Growth inhibition was evaluated by measuring the uptake of 3H-thymidine over a 4-hr pulse period after 2, 18, or 42 hr of monocyte-HeLa interaction. Inhibition of HeLa growth by monocytes was 23.8% +/- 8.6% over 6 hr, 22.0% +/- 8.9% over 22 hr. and 68.3% +/- 7.5% over 46 hr. Growth inhibition of HeLa cells was confirmed by direct enumeration of HeLa cells at the end of coincubation. Attachment of monocytes to the HeLa cells was confirmed by light and scanning electron micrographs. Granulocytes, lymphocytes, and other cell lines did not comparably inhibit HeLa growth and media replenishment did not ablate the effect. These data demonstrate that normal human monocytes can inhibit the growth of a malignant cell line in vitro in the absence of overt activation procedures.