Biomedical subjects
Publications and source records attributed to R S Miller.
Sturge-Weber syndrome (SWS) is a disorder involving central nervous system abnormalities that may increase the risk of hypothalamic-pituitary dysfunction. Records of 19 patients with suspected growth hormone deficiency (GHD), identified from a registry of 1653 patients with SWS, were reviewed; nine patients with GHD were found.
Gamma-ray emission from a narrow band at the galactic equator has previously been detected up to 30 GeV. We report evidence for a TeV gamma-ray signal from a region of the galactic plane by Milagro, a large-field-of-view water Cherenkov detector for extensive air showers. An excess with a significance of 4.5 standard deviations has been observed from the region of galactic longitude l E (40 degrees, 100 degrees) and latitude /b/ < 5 degrees. Under the assumption of a simple power law spectrum, with no cutoff in the EGRET-Milagro energy range, the measured integral flux is phi gamma(>3.5 TeV) = (6.4 +/- 1.4 +/- 2.1) x 10(-11) cm(-2) s(-1) sr(-1). This flux is consistent with an extrapolation of the EGRET spectrum between 1 and 30 GeV in this galactic region.
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BACKGROUND/OBJECTIVE: The efficacy of a direct factor (F)Xa inhibitor, ZK-807834, was compared with indirect inhibition by enoxaparin for inhibition and deaggregation of acute platelet-rich thrombi in a well-characterized porcine carotid injury model. METHODS: A crush injury was performed on a randomly chosen carotid artery and the thrombus allowed to propagate for 30 min. Pigs then received intravenous drug for 35 min: ZK-807834-Dose 1 (40 microg kg(-1) bolus + 1.5 microg kg(-1) min(-1) infusion, n=6); ZK-807834-Dose 2 (20 microg kg(-1) bolus + 0.75 microg kg(-1) min(-1) infusion; n=6); enoxaparin (1 mg kg(-1) bolus; n=6); or saline (n=6). Five minutes after drug initiation, the contralateral artery was injured. Thrombus size was monitored by scintillation detection of autologous 111In-platelets. RESULTS: The prothrombin time ratio was 2.2 +/- 0.1; 1.4 +/- 0.3; 1.2 +/- 0.9 and 1.1 +/- 0.2, respectively. ZK-807834-Dose 1 significantly inhibited carotid platelet deposition (525 +/- 226 x 10(6) cm(-2); P = 0.008), whereas ZK-807834-Dose 2 (2325 +/- 768) and enoxaparin (1236 +/- 383) were not different from saline (2776 +/- 642). Thrombus deaggregation was greatest for animals receiving ZK-807834-Dose 1 (473 +/- 185). Neither ZK-807834-Dose 2 (1588 +/- 480) nor enoxaparin (1618 +/- 686) was different from saline control (2222 +/- 598). CONCLUSIONS: Direct FXa inhibition with ZK-807834, at a prothrombin time ratio of 2.2, effectively inhibits thrombosis and promptly deaggregates thrombi induced by arterial injury. In contrast, indirect FXa inhibition with enoxaparin was ineffective.
BACKGROUND/OBJECTIVE: To test the hypothesis that circulating platelets display evidence of interactions with atherogenesis, platelet capacity to express P-selectin and propensity for spontaneous microaggregation in vitro were measured in samples from normal donors (N), patients with asymptomatic advanced coronary calcification (CC) or acute coronary syndromes (AC). To measure the effect of angioplasty on platelet function, samples obtained before, 30 min after and 24 h after angioplasty were compared. PATIENTS/METHODS: Platelet P-selectin was measured after maximal stimulation with thrombin. Microaggregation was measured as a platelet count deficit in citrate-anticoagulated platelet-rich plasma (PRP) relative to EDTA-anticoagulated blood. RESULTS: P-selectin expression was significantly lower for platelets from patients with either AC or CC compared to normals. In addition, platelets from AC and CC patients have a significantly greater propensity to form microaggregates in citrate anticoagulant. After angioplasty, the PRP-platelet count decreased transiently. CONCLUSION: Both acute unstable and chronic stable coronary disease are associated with an increased share of platelets unable to express P-selectin and an increased share of platelets that microaggregate in citrate anticoagulant. The genesis of these platelet characteristics is not fully explained by focal acute arterial injury and may reflect exposure to systemic atherosclerosis or the atherogenic process.
During a survey for possible rickettsial vectors in villages of the central part of the Thai-Myanmar border from September 2001 to February 2002, four species of fleas were collected from common peridomestic animals. All fleas were tested by PCR to detect DNA of bacteria of the genera Rickettsia (gltA and ompB genes) and Bartonella (ITS and ftsZ genes). Sequencing of PCR-amplified products was done using gltA fragments for Rickettsia and ftsZ fragments for BARTONELLA: Two genotypes related to Rickettsia felis were identified in three Ctenocephalides canis and one C. felis specimen. Further, the following Bartonella spp. were detected: Bartonella henselae in two C. felis specimens; Bartonella clarridgeiae in three C. felis specimens; and a new Bartonella genotype in one Nosopsylla fasciatus specimen. Rickettsia and Bartonella may be frequently detected in fleas infesting peridomestic animals from the western border of Thailand.
Forty-four Plasmodium falciparum isolates from Bangladesh and 22 from western Thailand were successfully tested for their drug susceptibility. High degrees of resistance were observed against chloroquine with geometric mean IC50s of 114.25 and 120.5 nM, respectively, for Bangladesh and western Thailand. Most isolates from both sites were sensitive to quinine, and all were sensitive to artesunate. Many isolates were considered in vitro resistant to mefloquine, but the geometric mean IC50 for the Thai isolates (98.79 nM) was 1.6 times (P = 0.002) higher than that of isolates from Bangladesh (60.3 nM). The high prevalence of in vitro mefloquine resistance in Bangladesh suggests that close surveillance is necessary to delay widespread multidrug resistant problems in the area.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
Microscopic detection of parasites has been the reference standard for malaria diagnosis for decades. However, difficulty in maintaining required technical skills and infrastructure has spurred the development of several nonmicroscopic malaria rapid diagnostic devices based on the detection of malaria parasite antigen in whole blood. The ParaSight F test is one such device. It detects the presence of Plasmodium falciparum-specific histidine-rich protein 2 by using an antigen-capture immunochromatographic strip format. The present study was conducted at outpatient malaria clinics in Iquitos, Peru, and Maesod, Thailand. Duplicate, blinded, expert microscopy was employed as the reference standard for evaluating device performance. Of 2,988 eligible patients, microscopy showed that 547 (18%) had P. falciparum, 658 (22%) had P. vivax, 2 (0.07%) had P. malariae, and 1,750 (59%) were negative for Plasmodium. Mixed infections (P. falciparum and P. vivax) were identified in 31 patients (1%). The overall sensitivity of ParaSight F for P. falciparum was 95%. When stratified by magnitude of parasitemia (no. of asexual parasites per microliter of whole blood), sensitivities were 83% (>0 to 500 parasites/microl), 87% (501 to 1,000/microl), 98% (1,001 to 5,000/microl), and 98% (>5,000/microl). Device specificity was 86%.
We describe the changing epidemiology of drug resistant malaria in Thailand over the past decade. Factors determining the characteristic patterns of the development and spread of resistance to anti-malarial drugs on the Thai-Cambodian border and the Thai-Myanmar border are explored, namely, population dynamics, drug usage and malaria control measures. The introduction of artesunate-mefloquine combination in selected areas along the two borders in 1995 is believed to be one of the multiple factors responsible for stabilizing the multidrug resistance problems in Thailand today. Other control measures and inter-governmental co-operation must continue to be strengthened in order to limit the spread of drug resistance malaria in the Southeast Asian region.
Air rifles, or BB guns, are generally thought of as childhood toys. Although most injuries are not serious, life-threatening events have been reported. Within a 1-year period, 3 boys presented after BB gun shots to the chest, all requiring surgical intervention for penetrating injuries to the heart. A 15-year-old underwent window pericardiotomy for hemopericardium with thrombus 24 hours after admission. Another, 5 years of age, underwent emergent exclusion of the cardiac apex for a traumatic ventricular septal defect. The third, 8 years old, had a right ventricular injury requiring an urgent subxiphoid pericardial window for tamponade. All recovered uneventfully. Increased public awareness, adult supervision, safety training, and appropriate legislation are needed to decrease the risks of these potentially lethal weapons.
BACKGROUND/PURPOSE: Abdominal compartment syndrome (ACS) is defined as cardiopulmonary or renal dysfunction caused by an acute increase in intraabdominal pressure. Although the condition is well described in adults, particularly trauma patients, little is known about ACS in children. METHODS: Three girls, ages 4, 5, and 5 years, were treated for ACS by silo decompression. Each child presented in profound shock, required massive fluid resuscitation, and had tremendous abdominal distension. The first child sustained a thoracoabdominal crush injury, underwent immediate celiotomy for splenic avulsion and a liver laceration, and required decompression 5 hours postoperatively. The second underwent ligation of her bluntly transected inferior vena cava; because of massive edema, her abdominal wall could not be closed, and prophylactic decompression had to be performed. The third presented with shock of unknown etiology, and ACS developed acutely with a bladder pressure of 26 mm Hg. RESULTS: Respiratory, renal, and hemodynamic function improved immediately in all 3 patients after decompression. Subsequently, each child underwent abdominal wall reconstruction and recovered uneventfully. CONCLUSIONS: ACS is a potentially lethal complication of severe trauma and shock in children. To prevent the development of renal or cardiopulmonary failure in these patients, decompression should be considered for acute, tense abdominal distension.
Cutaneous leishmaniasis is acquired from the bite of an infected sand fly and can result in chronic skin lesions that develop within weeks to months after a bite. Local trauma has been implicated as a precipitating event in the development of skin lesions in patients who have been infected with Leishmania species. Here we report a case series and review the literature on patients who developed cutaneous leishmaniasis after local trauma, which may familiarize clinicians with this presentation.
OBJECTIVE: To examine a subgroup of severely injured patients spending > or = 3 weeks in the intensive care unit (ICU) and to determine their disposition and eventual functional outcome. METHODS: A retrospective review of our trauma registry and medical records over a 7-year period (January of 1991 to December of 1997) identified 115 patients with ICU length of stay (LOS) > or = 3 weeks. Variables selected included age, length of stay, injury severity score, injuries, disposition, and charges. Functional independence measures (FIM) were obtained in patients requiring inpatient rehabilitation and a written questionnaire (Rand 36-item Health Survey) was mailed to all patients alive at discharge. RESULTS: Mean ICU length of stay of the 115 patients was 36 days (range, 21-106 days); mean age, 49 years (range, 4-89 years); 73 patients (63%) were males, 42 patients (37%) were females. Overall mortality was 22% (n = 25). The remaining 90 patients survived to discharge with the following disposition: rehabilitation facility 60% (n = 54), home with temporary disability 22% (n = 20), nursing home 8% (n = 7), home with permanent disability 4% (n = 4), transferred 6% (n = 5). Mean hospital charge was $193,000 (range, $77,000-$528,000). No variable or combination could predict outcome except age. Elderly patients (age > or = 75, n = 24) had an overall mortality of 42% (n = 10). Eight of 14 survivors fulfilled admission criteria and entered our rehabilitation facility. The remaining six elderly patients either went to nursing homes or were permanently disabled. Complete FIM scores were available on 47 of 54 patients who went to rehabilitation facility. The mean rehabilitation facility admission FIM score was 52, indicating either complete dependence or the need for moderate assistance. After they had remained at the rehabilitation facility for a mean of 48 days (range, 7-278 days), patients' FIM scores improved to a mean of 86, signifying minimal contact assistance or supervision only. Three-month follow-up FIM scores continued to improve to a mean of 101, a score denoting complete independence. Elderly patients within the rehabilitation facility fared as well as the younger group. For the Rand-36 survey, 47 of 90 patients or family members were contacted. Twelve patients died since discharge, leaving 35 patients to complete the survey. Despite excellent FIM scores, overall mean health was only fair to good, with limitations to activity and lack of energy cited as the main problems. CONCLUSION: Despite tremendous resource utilization, the majority of trauma patients with prolonged ICU stays can eventually return to varying degrees of functional daily living and independence, but not to preinjury levels. A subgroup of severely injured elderly patients had a significantly higher mortality rate. However, elderly survivors that entered our rehabilitation facility fared as well as the younger patients.
Pesticides used in agriculture may cause adverse health effects among the population living near agricultural areas. However, identifying the populations most likely to be exposed is difficult. We conducted a feasibility study to determine whether satellite imagery could be used to reconstruct historical crop patterns. We used historical Farm Service Agency records as a source of ground reference data to classify a late summer 1984 satellite image into crop species in a three-county area in south central Nebraska. Residences from a population-based epidemiologic study of non-Hodgkin lymphoma were located on the crop maps using a geographic information system (GIS). Corn, soybeans, sorghum, and alfalfa were the major crops grown in the study area. Eighty-five percent of residences could be located, and of these 22% had one of the four major crops within 500 m of the residence, an intermediate distance for the range of drift effects from pesticides applied in agriculture. We determined the proximity of residences to specific crop species and calculated crop-specific probabilities of pesticide use based on available data. This feasibility study demonstrated that remote sensing data and historical records on crop location can be used to create historical crop maps. The crop pesticides that were likely to have been applied can be estimated when information about crop-specific pesticide use is available. Using a GIS, zones of potential exposure to agricultural pesticides and proximity measures can be determined for residences in a study.