Charged particle radiography.

New applications of charged particle radiography have been developed over the past two decades that extend the range of radiographic techniques providing high-speed sequences of radiographs of thicker objects with higher effective dose than can be obtained with conventional radiographic techniques. In this paper, we review the motivation and the development of flash radiography and in particular, charged particle radiography.

Effects of chronic doxepin and amitriptyline administration in naïve mice and in neuropathic pain mice model.

Neuropathic pain is a severe clinical problem, often appearing as a co-symptom of many diseases or manifesting as a result of damage to the nervous system. Many drugs and agents are currently used for the treatment of neuropathic pain, such as tricyclic antidepressants (TCAs). The aims of this paper were to test the effects of two classic TCAs, doxepin and amitriptyline, in naïve animals and in a model of neuropathic pain and to determine the role of cytokine activation in the effects of these drugs. All experiments were carried out with Albino-Swiss mice using behavioral tests (von Frey test and the cold plate test) and biochemical analyses (qRT-PCR and Western blot). In the mice subjected to chronic constriction injury (CCI), doxepin and amitriptyline attenuated the symptoms of neuropathic pain and diminished the CCI-induced increase in the levels of spinal interleukin (IL)-6 and -1ß mRNA, but not the protein levels of these cytokines, measured on day 12. Unexpectedly, chronic administration of doxepin or amitriptyline for 12 days produced allodynia and hyperalgesia in naïve mice. The treatment with these drugs did not influence the spinal levels of IL-1ß and IL-6 mRNA, however, the protein levels of these pronociceptive factors were increased. The administration of ondansetron (5-HT3 receptor antagonist) significantly weakened the allodynia and hyperalgesia induced by both antidepressants in naïve mice; in contrast, yohimbine (α2-adrenergic receptors antagonist) did not influence these effects. Allodynia and hyperalgesia induced in naïve animals by amitriptyline and doxepin may be associated with an increase in the levels of pronociceptive cytokines resulting from 5-HT3-induced hypersensitivity. Our results provide new and important information about the possible side effects of antidepressants. Further investigation of these mechanisms may help to guide decisions about the use of classic TCAs for therapy.

Information technology for children's health and health care: report on the Information Technology in Children's Health Care Expert Meeting, September 21-22, 2000.

In September 2000, the Agency for Healthcare Quality and Research and the American Academy of Pediatrics Center for Child Health Research sponsored a meeting of experts and knowledgeable stakeholders to identify 1) the special information needs of pediatric care and 2) health service research questions related to the use of information technology in children's health care. Technologies that support the care of children must address issues related to growth and development, children's changing physiology, and the unique diseases of children and interventions of pediatric care. Connectivity and data integration are particular concerns for child health care workers. Consumer health information needs for this population extend beyond the needs of one individual to the needs of the family. Recommendations of the attendees include rapid implementation of features in electronic health information systems that support pediatric care and involvement of child health experts in policy making, standards setting, education, and advocacy. A proposed research agenda should address both effectiveness and costs of information technology, with special consideration for the needs of children, the development and evaluation of clinical decision support in pediatric settings, understanding of the epidemiology of iatrogenic injury in childhood, supplementation of vocabulary standards with pediatrics-specific terminology, and improvement in health care access for children, using telemedicine.

Induction of mixed apneas by inhalation of 100% oxygen in preterm infants.

Administration of 100% O2 to preterm infants induces an apnea that is usually central. We hypothesized that this apnea may be "mixed" at times with an obstructive component appearing late during the respiratory pause. In addition, we reasoned that obstruction would depend on the duration of the apnea. Thus, we gave 100% O2 to 61 healthy preterm infants. Group 1 was > or = 1,500 g [birth wt 1.8 +/- 0.1 (SE) kg, gestational age 32 +/- 1 wk, postnatal age 19 +/- 2 days, n = 26] and group 2 was < 1,500 g [birth wt 1.2 +/- 0.1 kg, gestational age 29 +/- 1 wk, postnatal age 30 +/- 4 days, n = 35]. Ventilation was measured using a flow-through system. Respiratory efforts in the absence of flow were detected using chest and abdominal displacements or diaphragmatic electromyography. In group 1, 19% of the central apneas became obstructive at 17 +/- 3 s, whereas in group 2, 34% did so at 12 +/- 2 s. Mixed apneas were longer than those without obstruction (28 +/- 3 vs. 12 +/- 1 s; P = 0.0001). The incidence of mixed apneas was 0, 14, and 66% in group 1 and 0, 27, and 69% in group 2 in apneas of 3-10, 11-20, and > 20 s, respectively. These findings suggest that 1) a percentage of the central apneas induced by inhaling 100% O2 became obstructive, 2) the incidence of the obstructive component increased with the duration of apnea, and 3) smaller infants became obstructed sooner and had a higher incidence of obstruction than larger infants.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of inhaled oxygen (up to 40%) on periodic breathing and apnea in preterm infants.

To discover whether increases in inhaled O2 fraction (FIO2; up to 40%) decrease apnea via an increase in minute ventilation (VE) or a change in respiratory pattern, 15 preterm infants (birth weight 1,300 +/- 354 g, gestational age 29 +/- 2 wk, postnatal age 20 +/- 9 days) breathed 21, 25, 30, 35, and 40% O2 for 10 min in quiet sleep. A nosepiece and a flow-through system were used to measure ventilation. Alveolar PCO2, transcutaneous PO2, and sleep states were also assessed. All infants had periodic breathing with apneas greater than or equal to 3 s. With an increase in FIO2 breathing became more regular and apneas decreased (P less than 0.001). This regularization in breathing was not associated with significant changes in VE. However, the variability of VE, tidal volume, and expiratory and inspiratory times decreased significantly. The results indicate that the more regular breathing observed with small increases in FIO2 was not associated with significant changes in ventilation. The findings suggest that the increased oxygenation decreases apnea and periodicity in preterm infants, not via an increase in ventilation, but through a decrease in breath-to-breath variability of VE.

Effect of baseline oxygenation on the ventilatory response to inhaled 100% oxygen in preterm infants.

We tested the hypothesis that the immediate (< 1 min) ventilatory response to 100% O2 in preterm infants, a test of peripheral chemoreceptor activity characterized by a decrease in ventilation due to apnea, is more pronounced at lower baseline O2 concentrations. We studied 12 healthy preterm infants [birth weight 1,425 +/- 103 (SE) g; study weight 1,670 +/- 93 g; gestational age 30 +/- 1 wk; postnatal age 27 +/- 7 days] during quiet sleep. The infants inhaled 15, 21, 25, 30, 35, 40, and 45% O2 for 5 min in a randomized manner (control period), followed by 100% O2 for 2 min, and then the same initial O2 concentration again for 2 min (recovery period). A nose piece and a flow-through system were used to measure ventilation. The immediate decrease in ventilation with 100% O2 was 46% on 15% O2, 24% on 21% O2, 11% on 25% O2, 8% on 30% O2, 12% on 35% O2, and 8% on 40% O2; there was no decrease on 45% O2 (P < 0.01). The corresponding mean duration of apnea was 29 s during 15% O2, 18 s during 21% O2, 8 s during 25% O2, 9 s during 30 and 35% O2, and 3 s during 40% O2; only one infant developed a 5-s apnea during 45% O2 (P < 0.001). The findings suggest that 1) the ventilatory decrease in response to 100% O2 is dependent on the baseline oxygenation, being more pronounced the lower the baseline O2 concentration; and 2) this ventilatory decrease is entirely related to more prolonged apneas observed with lower baseline O2 concentrations. We speculate that the peripheral chemoreceptors, being so active in the small preterm infant with relatively low arterial PO2, are highly susceptible to changes in PO2, and this makes them prone to irregular or periodic breathing, especially during sleep.

A respiratory sensory reflex in response to CO2 inhibits breathing in preterm infants.

Traditionally, the increase in ventilation occurring after approximately 4 s of CO2 inhalation in preterm infants has been attributed to an action at the peripheral chemoreceptors. However, on a few occasions, we have observed a short apnea (2-3 s) in response to 3-5% CO2 in these infants. To test the hypothesis that this apnea reflects a respiratory sensory reflex to CO2, we gave nine preterm infants [birth wt 1.5 +/- 0.1 (SE) kg, gestational age 31 +/- 1 wk] 7-8% CO2 while they breathed 21% O2. To study the dose-response relationship, we also gave 2, 4, 6, and 8% CO2 to another group of seven preterm infants (birth wt 1.5 +/- 0.1 kg, gestational age 31 +/- 1 wk). In the first group of infants, minute ventilation during 21% O2 breathing (0.232 +/- 0.022 l.min-1.kg-1) decreased after CO2 administration (0.140 +/- 0.022, P < 0.01) and increased with CO2 removal (0.380 +/- 0.054, P < 0.05). This decrease in ventilation was related to an apnea (12 +/- 2.6 s) occurring 7.7 +/- 0.8 s after the beginning of CO2 inhalation. There was no significant change in tidal volume. In the second group of infants, minute ventilation increased during administration of 2, 4, and 6% CO2 but decreased during 8% CO2 because of the presence of an apnea. These findings suggest that inhalation of a high concentration of CO2 (> 6%) inhibits breathing through a respiratory sensory reflex, as described in adult cats (H. A. Boushey and P. S. Richardson. J. Physiol. Lond. 228: 181-191, 1973).(ABSTRACT TRUNCATED AT 250 WORDS)

Inhalation of low (0.5%-1.5%) CO2 as a potential treatment for apnea of prematurity.

Apnea of prematurity is common and none of the treatments being used are fully effective and free of significant adverse side effects. We hypothesized that low concentrations of CO2 (< or = 1.5%) may reduce apnea without causing discomfort from an increase in ventilation. We studied 10 preterm infants at a gestational age of 32+/-1 wk (mean +/- SEM) and birthweight 1.8+/-0.2 kg. After a control period of 1 hour, concentrations of CO2 were given (0.5%, 1%, and 1.5%) for 1 hour each, followed by a recovery period of 1 hour. Apnea number significantly decreased from 2.0+/-0.3 apneas/min during control to 1.0+/-0.1 apneas/min (0.5% CO2; P < .05), 1.1+/-0.2 (1% CO2; P < .05), and to 0.7+/-0.2 (1.5% CO2; P < .01). The apnea time significantly decreased from 14.2+/-2.5 s/min during control to 5.2+/-0.8 (0.5% CO2; P < .01), 5.8+/-0.7 (1% CO2; P < .01), and to 3.7+/-0.9 (1.5% CO2; P < .01). Minute ventilation significantly increased with CO2 without evidence of respiratory discomfort. TcPCO2 did not change and TcPO2 increased slightly. These findings suggest that inhalation of low concentrations of CO2 in preterm infants with apnea 1) decreases the number and time of apneas, 2) improves oxygenation, 3) increases ventilation, and 4) is effective even in such low concentrations as 0.5%. We speculate that inhalation of CO2 (< 1%) is more effective and safer than methylxanthines for the treatment of apnea of prematurity.

The biphasic ventilatory response to hypoxia in preterm infants is not due to a decrease in metabolism.

The mechanism underlying the biphasic ventilatory response to hypoxia in neonates is poorly understood. Because alveolar PCO2 (PaCO2) decreases and remains low during hypoxia, it has been argued that a decrease in metabolism may occur. We hypothesized that if the late decrease in ventilation during hypoxia is due to a decrease in CO2 production, an increase in PACO2 should abolish it. We studied 27 preterm infants [birth weight, 1,700 +/- 41 g (mean +/- SEM); study weight, 1,760 +/- 36 g; gestational age 32 +/- 0.2 weeks; postnatal age, 17 +/- 1 days]. A flow-through system and Beckman analyzers were used to measure ventilation and alveolar gases. Metabolism was expressed as changes in oxygen consumption. Infants were studied randomly during hypoxia alone (15% O2 + N2, n = 55) and during hypoxia plus CO2 (0.5% CO2, n = 30; 2% CO2, n = 10). Each experiment consisted of 2 minutes of control measurements (21% O2), 5 minutes of measurements during hypoxia alone or hypoxia plus CO2, followed by 2 minutes of recovery (21% O2). We found a biphasic response to hypoxia with or without CO2 supplementation, the percent change in ventilation from initial peak hyperventilation to late hypoventilation at 5 minutes being -16 +/- 2 on 15% O2; -9 +/- 3 on 15% O2 + 0.5% CO2; and -15 +/- 9 on 15% O2 + 2% CO2 (P < 0.05). The decrease in ventilation was primarily due to a significant decrease in frequency; tidal volume increased. Oxygen consumption decreased similarly with the various inspired gas mixtures during hypoxia. These findings indicate that the decrease in ventilation during hypoxia is unlikely to be solely due to a decrease in metabolism since the late decrease in ventilation following initial hyperventilation still occurred despite the elimination of a fall in PACO2. We speculate that the mechanism underlying the late decrease in ventilation is likely of central origin, probably mediated through the release of inhibitory neurotransmitters.

The effect of nasal occlusion on the initiation of oral breathing in preterm infants.

The ability to switch from nasal to oral breathing in response to nasal obstruction is crucial for survival, and has been suggested to be an important mechanism in preventing sudden infant death syndrome (SIDS). To know whether the ability to switch from nasal to oral breathing is uniformly present during the early neonatal period, we examined the effects of slow and fast nasal occlusions on the establishment of oral breathing in preterm infants. Slow occlusions were used to mimic more closely occlusions occurring spontaneously. We studied 17 healthy preterm infants [birth weight, 1830 +/- 27 g (mean +/- SE); study weight, 1800 +/- 109 g; gestational age, 32 +/- 1 weeks; postnatal age, 12 +/- 2 days]. We used a nosepiece with a nasal occluder and a flow-through system to measure ventilation. A CO2 sampling catheter at the mouth was used to detect oral breathing. Of 58 occlusions, 29 were slow [resistance increasing slowly from 0 to infinite (occlusion)], and 29 were fast (infinite elastance applied in < 1 sec). Oral breathing was always established following slow and fast occlusions. In 44% of the slow occlusions, oral breathing started before complete occlusion. Arousal was observed in 12/58 (17%) of all occlusions, occurring primarily after initiation of oral breathing. Oxygen saturation and respiratory rate decreased significantly following occlusions, from 96 +/- 0.6 to 87 +/- 1.2% and 49 +/- 2.8 to 38 +/- 2 breaths/min, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

The incidence of obstructive apneas in preterm infants with and without bronchopulmonary dysplasia.

We tested the hypotheses that (1) preterm infants with bronchopulmonary dysplasia (BPD) have an increased incidence of obstructive apneas as compared to those without BPD (control) and (2) the respiratory pattern during obstructive apneas may be associated with more pronounced hypoventilation. Ventilation was measured with a flow-through system. We examined 2929 total apneas in 12 infants with BPD and 4366 apneas in 12 control infants matched for study weight (1.51 +/- 0.11 kg in the BPD group and 1.62 +/- 0.12 kg in the control group, P = 0.6) and for postconceptional age (33.3 +/- 0.8 weeks in the BPD group compared with 33.4 +/- 0.7 weeks in the control group, P = 0.6). The incidence of central apneas predominated in the BPD group (2551/2929, 87%) and in the control group (4188/4366, 96%). Obstructive apneas were more frequent in the BPD group (378/2929, 13%) than in the control group (178/4366, 4%, P = 0.004). The increased incidence of obstructive apneas in infants with BPD was observed in Quiet sleep (9.1 vs. 1.6%, P = 0.03) and in REM sleep (14.2 vs. 3.6%, P = 0.009). This increased incidence of obstructive apneas was applicable to short apneas (< 10 s, 10.9 vs. 2.7%, P = 0.003) and long apneas (> 10 s, 27.5 vs. 16.4%, P = 0.01). There were no significant changes in ventilatory pattern that could be uniquely attributed to one type of apnea. The findings suggest: (1) the great variability in the incidence of obstructive apneas reported in the literature relates, at least in part, to the clinical status of the infants and (2) ventilatory pattern is not a useful predictor of either type of apnea.

The usage of frozen allografts of the spongy bone in filling the loss of bone after loosening of the hip prosthesis.

The authors present the way of using allogenic, frozen, radio-sterilizated, spongy bone grafts in operational reconstructing the defects of bone stock caused by loosening of the hip prosthesis. The bone grafts were sterelizated by radiation, formed in cubes and it had the fat removed. The operational reconstruction of the spongy bone was performed according to the method described by E. Gee, R. Ling and T.J.J.H. Sioof. Thirty five operations of the revision hip arthroplasty with using the bone grafts were made since 1995. Just before transplantation the grafts were morselised to pieces of size 3 x 3 x 3 mm and then stuck in the place of the defect. Rebuilding of the morselised grafts of the spongy bone starts from activating osteoblasts, while the same process in the compact bone starts with osteolysis by activating osteoclasts. The mechanical durability of these grafts is also very high. We claim that the biological connection between the host bone and the graft forms in a couple of weeks, but the forming of a solid, fully functional bone takes about few months. Only radiological examination shows the stage of allografts incorporation into host's skeleton. Between these 35 operations 2 patients needed to be operated again, because of the grafts resorption. In conclusion, operative revision hip arthroplasty to require the special operating tools large quantities spongy bone allografts.

Frozen allogenic spongy bone grafts in filling the defects caused by fractures of proximal tibia.

The authors present the way of using the allogenic, frozen, radio-sterilized, spongy bone grafts in operational filling of defects after infra-articular fracture of proximal tibia. Fifteen patients (11 men and 4 women) classified between 30 and 66 years old were evaluated. These patients were operated from 1996 to 1998. The operational treatment with using frozen spongy bone grafts was performed on patients with comminuted split fracture of lateral condyle and depression of tibial plateau. In each case after elevating depressed fragment of tibial plateau bone grafts and screws were used to create a stable joint surface. In the same time other injured structures of the joint (ligaments, meniscus) were being reconstructed. To evaluate the stage of grafts incorporation, radiological examinations were made in; 4 weeks, 8 weeks, 6 months, 1 year from the date of the operation. We observed the process of calcification and forming trabeculac in bone grafts. The mechanical abilities of the reconstructed joint were evaluated according to the IKDS and Lysholm score. In all cases the spongy bone grafts in the joint were reconstructed and rebuild successfully. Thirteen patients had good and very good results in further clinical examinations. We claim that frozen, allogenic grafts of the spongy bone are very useful in filing detects of that bone caused by complicated injuries. This method of treatment with its good results is recommended.

Linking personal and public health information: a vision for community-centered health information systems.

As health care in the U.S. and worldwide has shifted from a centralized, institution-based model to a distributed process occurring largely in the communities, Integrated Advanced Information Management Systems (IAIMS) initiatives must also move toward addressing the challenges of integrating health information at the community level. The Wisconsin IAIMS initiative strives to create such a solution, anchoring its efforts in a regional health information technology architecture by partnering with Wisconsin-area communities as the foundation that will ensure the establishment of the appropriate collaborations to gain adequate investment and generate sustainable solutions for health information integration.

[Allogeneic transplantation in reconstruction of cruciate ligaments in the knee joint]. / Przeszczepy allogenne w rekonstrukcji wiezadel krzyzowych stawu kolanowego.

Allografts have been used successfully by orthopaedic surgeon for reconstructing ligaments, including intraarticular reconstructions of cruciate ligaments. This type of grafts are particularly attractive alternative for reconstruction surgery because donor site morbidity is eliminated, operative time is shorter, incision can be smaller and the availability of different transplant sizes is almost unlimited. This article offers some summaries of scientific background on ACL reconstruction with allografts in animals, clinical follow-up in the humans and discussions on the risk of disease transmission, secondary sterilization, incorporation and remodeling of the allografts after transplantation.

[Foreign body of the bronchus in adults]. / Ciala obce w oskrzelach osób doroslych.

Two cases of endobronchial foreign bodies are presented. In both an uneventful clinical course following removal of the foreign body and antibacterial therapy was observed. The authors diagnostical problems in cases with scant symptoms, especially presence of non-specific symptoms and uncharacteristic medical history.

[The value of anti-inflammatory effectiveness of Apranax 550 and Voltaren 50 after knee joint arthroscopic surgery]. / Cena skutecznosci przeciwzapalnej Apranaxu 550 i Voltarenu 50 po operacjach artroskopowych stawu kolanowego.

The results are presented of the study of the effectiveness of non-steroid anti-inflammatory drugs (Apranax, Voltaren) on the basis of observation of 60 patients in a double blind trial after knee joint arthroscopic operations. The administration of Apranax 550 or Voltaren 50 within the period of 10 days after the operation decreased significantly the incidence of inflammatory reactions. Apranax 550 was acting more rapidly and more effectively in elimination of clinical signs and symptoms of inflammation, and the patients were not reporting any adverse effects.

Rehabilitation following revision hip arthroplasty using morselized bone grafts.

For over 25 years, arthroplasty has been in general use as a means of treating degenerative changes in the coxofemoral joint. Loosening of the hip prosthesis is often observed, accompanied by bone defects in the area enveloping the prosthesis. This constitutes an indication for revision surgery.
The authors present their own technique for rehabilitation following revision hip arthroplasty using frozen morselized bone grafts. The procedures used in such cases should be highly individualized. It is necessary to apply a controlled early load on the operated limb at bedside. The authors emphasize the necessity to reduce flexion contracture of the joint. Full load on the limb is proposed between the 4th and 6th month after surgery, depending on the extent of the reconstructed bone defects.

Results of treatment of aseptic loosening of hip prostheses using frozen spongy bone allografts.

BACKGROUND: [corrected] The authors present the results of treatment of aseptic loosening of hip prostheses using frozen allogenic spongy bone grafts. MATERIAL AND METHODS: 34 patients (8 men and 26 women) between 34 and 79 years of age were evaluated. These patients all underwent revision hip arthroplasty during the period from 1995 to 1998. Surgical treatment using frozen spongy bone grafts was performed on patients with defects of the acetabulum and femur after loosening of hip prostheses. In each case bone grafts were used for acetabular and femoral reconstruction. To evaluate the progress of graft incorporation, radiological examinations were made at 6 weeks, 3 months, 6 months, 1 year and 2 years after the date of surgery. We observed the process of calcification abilities of the reconstructed structures were evaluated according to the Merle d'Aubigne-Postel scale. RESULTS: In all cases the spongy bone grafts were reconstructed and rebuilt successfully. 24 patients had good results in further clinical examinations. We argue that frozen allogenic grafts of spongy bone are very useful in filling acetabular and femoral defects in aseptic loosening of hip prostheses. CONCLUSIONS: This method of treatment provides good results and should recommended.

Qualitative comparison of bremsstrahlung X-rays and 800 MeV protons for tomography of urania fuel pellets.

We present an assessment of x-rays and proton tomography as tools for studying the time dependence of the development of damage in fuel rods. We also show data taken with existing facilities at Los Alamos National Laboratory that support this assessment. Data on surrogate fuel rods have been taken using the 800 MeV proton radiography (pRad) facility at the Los Alamos Neutron Science Center (LANSCE), and with a 450 keV bremsstrahlung X-ray tomography facility. The proton radiography pRad facility at LANSCE can provide good position resolution (<70 µm has been demonstrate, 20 µm seems feasible with minor changes) for tomography on activated fuel rods. Bremsstrahlung x-rays may be able to provide better than 100 µm resolution but further development of sources, collimation, and detectors is necessary for x-rays to deal with the background radiation for tomography of activated fuel rods.