Biomedical subjects
Publications and source records attributed to C Y Kuo.
Spontaneous perforation of pyometra is an extremely rare emergent gynecologic disease. We report a 73-year-old woman with a spontaneously perforated pyometra presenting with acute abdomen in the emergency department. A dedicated computed tomography examination of the abdominal and pelvic regions revealed the diagnosis. The patient recovered well after surgical intervention and antibiotic treatment.
Aerosol samples for PM(2.5) and PM(2.5-10) were collected at four locations in central Taiwan from 26 to 31 March 2000, a period that experienced exceedingly high PM levels from 29 to 30 March due to the passage of an Asian dust storm. The samples were analyzed for mass, metallic elements, ions, and carbon. The purpose of this paper is to investigate the influence of the dust storm on the characteristics of local ambient particulate matter. The results indicate that the concentrations of the crustal elements Ca, Mg, Al, Fe and the sea salt species Na+ and Cl- in PM(2.5-10) during the dust episode exceed the mean concentrations in the non-dust period by factors of 3.1, 2.9, 2.6, 2.2, 2.3 and 2.1 respectively. Enrichment factors of Ca, Fe, and Mg in PM(2.5-10) during the dust event are close to unity, indicating that these elements are from soil. Reconstruction of aerosol compositions revealed that soil of coarse particulates elevated approximately 50% in the dust event. It is noted that during the dust event, the ratio of Mg/Al in PM(2.5-10) ranged from 0.21 to 0.25 while that of Ca/Al ranged from 0.6 to 0.9, levels more constant than those obtained in non-dust period.
Tuberculosis remains an important cause of infection in chronic haemodialysis patients. Frequent extrapulmonary involvement, non-specific presentation and limited diagnostic tools usually make early diagnosis difficult. Herein, we report on an 83-year-old female patient who had been on regular heamodialysis therapy for 15 years, who presented with asymptomatic hypercalcaemia and pancytopenia. Haemophagocytic syndrome was documented during the admission period. Mycobacterium tuberculosis was cultured from bone marrow 1 month after her demise. This case report highlights the non-specific manifestations of extrapulmonary tuberculosis in dialysis patients and the limited value of conventional diagnostic methods. We would like to recommend aggressive intervention and early tissue aspiration from possible infectious sites when tuberculosis cannot be completely ruled out. Disseminated tuberculosis should be considered as an indication of hypercalcaemia where haemophagocytic syndrome occurs simultaneously.
Three common sources of environmental exposure to particulate polycyclic aromatic hydrocarbons (PAHs) in Taiwan were chosen for this study. They are smoke of incense burning, exhausts of motor vehicles, and fumes of charcoal burning. The campus environment without any specific PAH sources (nonpoint sources) was chosen as the control. The particulate PAH concentrations in the air samples containing smoke of incense burning were only slightly higher than those in the control. However, the total concentration of particulate PAHs in the air samples with exhausts of motor vehicles and fumes of charcoal burning was about 7.5 times and 22 times higher than those observed in the control, respectively. The mean inhalation amounts of particulate PAHs per unit time are very high both in samples with exhausts of motor vehicles (13.9 ng/min) and fumes of charcoal burning (38.1 ng/min). The exposure dose of 22 PAHs per day ranged from 3.18 to 18.0 microg/day under four exposure conditions. Moreover, the personal inhalation BaP(eq) levels are in the range of 0.4 to 1.55 microg/day.
Functional neuromuscular stimulation (FNS)/functional electrical stimulation (FES) is a potential way to restore some functionality to the limbs of patients with spinal cord injury through direct/indirect stimulation of the motoneuron. One of the constraints for wider use of FNS on paraplegic patients is the lack of efficient control algorithm. Most of the published works on FNS/FES control are based on oversimplified models of human body dynamics. An innovative control strategy for stabilizing the standing posture of paraplegic patients is proposed here which is a combination of a proportional-plus-derivative controller for motions of the skeletal system and a control action prediction mechanism to produce musculotendon activation. The goal is to produce musculotendon torque which can approximate those demanded by the controller for the skeletal system. In computer simulations, using a detailed skeletal-musculotendon-muscle activation dynamics model of human body, this FNS/FES control approach can stabilize a paraplegic patient's standing posture with the minimum number of musculotendon groups. Also, it is found that this control strategy can maintain stability even in the presence of reasonable variations in the controller's musculotendon parameters.
BACKGROUND: Endothelin-1 (ET-1) is a novel and potent endothelium-derived vasoconstriction peptide present in human plasma. In this study, plasma ET-1 concentrations were determined and their physiological significance was evaluated in Taiwanese neonates with respiratory distress. METHODS: Sixty newborn infants consisting of 22 with respiratory distress syndrome (RDS), 13 with transient tachypnea of newborn (TTNB), 4 with meconium aspiration syndrome, 10 healthy preterm and 11 healthy full-term infants were included for plasma ET-1 determination. Plasma ET-1 levels were measured by enzyme immunoassay at the of age of 1 day. For those who were diagnosed with RDS, plasma ET-1 concentrations were scheduled for evaluation at the ages of 1, 2, 3, 7, 14, 28, and 35 days as long as oxygen was being used. RESULTS: On the first day of life, there was no significant difference in plasma ET-1 concentrations between healthy preterm and term infants (3.92 +/- 0.88 vs. 3.56 +/- 1.98 pg/mL, p = 0.606). However, plasma ET-1 concentrations of infants with RDS were significantly higher than those with TTNB (6.46 +/- 0.58 vs. 3.77 +/- 1.29 pg/mL, p < 0.001). In RDS infants, plasma ET-1 concentrations showed no significant difference between those who developed bronchopulmonary dysplasia (BPD, N = 4) and those who recovered (non-BPD, n = 18) (7.84 +/- 1.85 vs. 5.81 +/- 2.76 pg/mL, p = 0.242). CONCLUSION: Plasma ET-1 concentrations were similar in preterm and term infants. ET-1 concentrations were higher in infants with RDS than in infants with TTNB, which suggests that plasma ET-1 levels can be useful in the differential diagnosis. However, the plasma ET-1 concentrations can not be a predictor for BPD.
In order to test the hypothesis that endothelin-1 (ET-1) directly contributes to the pathophysiology of pulmonary hypertension induced by meconium aspiration, we randomized 12 anesthetized and paralyzed piglets to receive BQ-123, a selective endothelin-A receptor antagonist (BQ group), or normal saline (NS group) after meconium aspiration. The animals were instilled with meconium mixture (3 mL/kg) via an endotracheal tube, and then given intravenous BQ-123 (2 mg/hr) or normal saline. Plasma ET-1 concentrations, arterial blood gases, and hemodynamics were measured at baseline and at 60, 120, 180, and 240 minutes after instillation. The results showed that plasma ET-1 concentrations were similar in both groups. However, in the BQ group, pulmonary artery pressure was significantly lower after 120 minutes (p < 0.05 at 120 min, p < 0.01 at 180 and 240 min) and pulmonary vascular resistance was significantly lower after 180 minutes (p < 0.01) than in the NS group. No significant difference was found in systemic hemodynamics. These data suggest that ET-1 directly contributes to the pathophysiology of pulmonary hypertension induced by meconium aspiration.
OBJECTIVES: Candidaemia caused by Candida parapsilosis (CP) is being increasingly reported among infants in neonatal intensive care units (NICU). To assess relative severity, clinical manifestations of candidaemia caused by C. albicans (CA) and CP in a NICU were compared. METHODS: Between January 1994 and July 1997, episodes of candidaemia occurring among infants hospitalized in the NICU were identified in a children's hospital. The demographic characteristics, associated risk factors, clinical manifestations and outcome of the infants with CP fungaemia were collected and compared with those of the infants with CA fungaemia. RESULTS: Twenty-four episodes caused by CA and 22 episodes caused by CP were included in this study. No significant differences were found between the two groups for gestational age, birth weight, male gender, post-natal age at onset of candidaemia, frequency of antecedent neonatal events, prior duration of antibiotic therapy and hyperalimentation, as well as presence of central venous catheter (CVC). Infants with CA fungaemia were significantly more likely than those with CP fungaemia to present with hypoxaemia, bradycardia and respiratory distress requiring intubation, and have a longer prior duration of indwelling CVC and a higher dissemination rate. The eradication rate of candidaemia and overall case fatality rate were comparable in both groups. but CP fungaemia did not appear to cause acute lethal events. CONCLUSION: The presenting signs of CP fungaemia are relatively not so severe, but CP fungaemia, which is relatively difficult to eradicate, increases the morbidity and mortality of the infants.
We reviewed 62 episodes (from 59 infants) of neonatal candidemia that occurred between January 1994 and June 1999. Except 5 term babies, all infants were premature (median gestational age [GA], 30 weeks) and birth weight was less than 2,500 g (median, 1,300 g). Most infants had reported risk factors and other neonatal problems. The age at onset of candidemia ranged from 15 to 173 days with a median of 34 days. In addition to catheter removal, all but one infants received antifungal agents and candidemia was eradicated subsequently in 46 episodes (75%). Eighteen infants with 19 episodes ever received fluconazole therapy. Fluconazole was administered as the first line agent in 6 episodes and successfully cleared candidemia in 5 episodes. Fluconazole was used as an alternative agent in an additional 13 episodes after amphotericin B (am B) +/- flucytosine were given for a period without a satisfactory result and eradication of candidemia was achieved in 8 episodes subsequently. All 18 infants tolerated fluconazole well and no withdrawal was required on account of its adverse effect. In contrast, am B alone was administered as the first line agent in 55 episodes and successfully cleared candidemia in 32 episodes (58%). This retrospective analysis suggests that fluconazole appears to be safe in neonates and can be used as an alternative agent in treating neonatal candidemia. A large-scaled prospective study may be needed.
OBJECTIVES: This study evaluated the effect of the motorcycle helmet law implemented in Taiwan on June 1, 1997. METHODS: Collecting data on 8795 cases of motorcycle-related head injuries from 56 major Taiwanese hospitals, we compared the situation 1 year before and after implementation of the helmet law. RESULTS: After implementation of the law, the number of motorcycle-related head injuries decreased by 33%, from 5260 to 3535. Decreases in length of hospital stay and in severity of injury and better outcome were also seen. The likelihood ratio chi 2 test showed that severity decreased after the law's implementation (P < .001). Full helmets were found to be safer than half-shell helmets. CONCLUSION: The helmet law effectively decreased the mortality and morbidity from motorcycle-related head injuries.
BACKGROUND AND PURPOSE: Congenital diaphragmatic hernia (CDH) is a challenging condition and is associated with a high mortality rate; optimal therapy remains unclear. This retrospective study describes the clinical characteristics of treatment and outcome in 48 infants with CDH. METHODS: Twenty-eight male (58%) and 20 female (42%) infants with CDH were treated from 1987 through 1998. The goals of the ventilator strategy were permissive hypercapnea (PaCO2 < or = 55 mm Hg) and avoidance of hyperventilation. Infants were initially ventilated with an intermittent mandatory rate of 40 to 60 per minute, peak inspiratory pressure of 20 to 25 cm H2O, and positive end-expiratory pressure of 5 cm H2O. High-frequency positive pressure ventilation was used if hypoxemia or severe hypercapnea (PaCO2 > 60 mm Hg) occurred. Most infants underwent repair after 3 days of age and only four infants underwent early repair within 24 hours of birth. A prophylactic chest tube was placed in the ipsilateral hemithorax postoperatively in all patients treated before 1996. The severity of respiratory distress was estimated by alveolar-arterial oxygen difference, oxygenation index, and alveolar-arterial ratio. RESULTS: Forty-six patients presented with Bochdalek CDH, and two with Morgangni CDH. Antenatal diagnosis was made in 10 cases. Respiratory distress was the major manifestation and usually occurred immediately after birth. Six cases were diagnosed several months after birth and presented mainly with gastrointestinal symptoms. Eleven patients died before surgery and 37 patients underwent surgical repair. Two infants died postoperatively because of congestive heart failure and tension pneumothorax, respectively. The overall mortality rate was 27%. The major causes of mortality were severe respiratory failure, persistent pulmonary hypertension, pneumothorax, and associated anomalies. CONCLUSION: Nearly 75% of patients in this series survived. This suggests that noninvasive respiratory care combined with delayed surgery may be an acceptable strategy for the treatment of CDH, and can be used in most medical institutions without equipment for extracorporeal membrane oxygenation therapy.
BACKGROUND: This study focuses on the effect of carbon dioxide tension in the first 3 days of life on the development of retinopathy of prematurity (ROP) in mechanically ventilated premature infants. METHODS: From January 1997 to June 1998, 91 premature infants (gestational age 28.8 +/- 2.5 weeks, birth weight 1169 +/- 385 g) born in Chung Gung Children's Hospital requiring mechanical ventilation in the first 72 hours were enrolled in our study. Ophthalmic examination was performed initially at 4-6 weeks of age and then every week if ROP was found and every other week if the result was normal until discharge. These infants were divided into 2 groups: those with and without ROP. Medical records of the highest and lowest blood gas measurements were recorded during the first 3 days of life. To screen for possible risk factors related to the development of ROP within these 2 groups, variables comprising perinatal data were compared. RESULTS: The perinatal factors were compared, whish showed that infants with ROP had a lower mean gestational age (p < 0.001), mean birth body weight (p < 0.001), and a longer duration under mechanical ventilation (p < 0.001). The severity and incidence of ROP were not affected by either hypercapnia or hypocapnia; even with the superimposed effect of hyperoxia, the effect was minimal. CONCLUSION: Hypercarbia or hypocarbia in the first 3 days of mechanically ventilated preterm neonates does not affect the subsequent development of retinopathy of prematurity. However, a lower gestational age and birth weight as well as longer-duration mechanical ventilation might be independent predictors for the occurrence of ROP. The role of PaCO2 in the pathophysiology of retinopathy of prematurity remains undetermined, and further investigation in the future is warranted.
Idiopathic myelofibrosis is characterized by bone marrow fibrosis, anemia, leukoerythroblastosis, and extramedullary hematopoiesis in many organs. Renal abnormalities in idiopathic myelofibrosis have been rarely described in the literature and include extramedullary hematopoiesis in the pararenal or retroperitoneal areas resulting in obstructive uropathy and hemtopoietic cell infiltration in tubulointerstitial area and urolithiasis. These lead to azotemia or acute renal failure, which may respond well to radiotherapy and adjuvant chemotherapy. To our knowledge, there has been only one case report of nephrotic syndrome associated with glomerulonephritis in a myelofibrosis patient; however, no effective treatment was described. Herein, we report the case of a patient with idiopathic myelofibrosis who initially presented with hepatomegaly, anemia, and leukoerythroblastosis. A nephrotic syndrome developed 7 years after initial diagnosis. Renal biopsy disclosed the unique pathological finding of simultaneous mesangial proliferative glomerulonephritis, renal extramedullary hematopoiesis, and gouty nephropathy. Despite treatment with busulfan, proteinuria persisted that implied irreversible glomerular injury and a terminal prognosis. We focus on the unusual pathological finding and the association between nephrotic syndrome and idiopathic myelofibrosis.
Two young men with severe hypercalcemia in association with renal failure (one acute and one chronic) are reported in whom usual diagnostic tests failed to reveal an etiology, and the final diagnoses were given by bone marrow examinations. Early bone marrow examinations in specific patients with hypercalcemia of undetermined origin sometimes are vital as shown by our two patients.
We describe a patient with multiple myeloma which presented as a thoracic paraspinal tumor and myelomatous pleural effusion. He had manifested a gradual onset of upper back pain with radiation to the left chest wall for 3 months. A radiographic examination showed left pleural effusion and a paraspinal tumor with rib destruction at the--left T5-6 level. Laboratory data showed anemia and a reversed serum albumin to globulin ratio. Protein electrophoresis and immunoelectrophoresis showed a monoclonal IgG-lambda chain component in the serum, urine, and pleural effusion fluid. Ultrasound-guided transthoracic mass biopsy and thoracentesis were performed for diagnosis. Biopsy of the thoracic tumor showed a solid mass composed of immature plasma cells. The pleural effusion fluid contained numerous immature plasma cells. An immunophenotype study of the pleural effusion fluid revealed monoclonal plasma cells, compatible with malignant pleural effusion. A specimen of bone marrow was interpreted as typical for plasma cell myeloma. Local radiotherapy and chemotherapy with melphalan and prednisolone resulted in good partial remission with a stable condition. Later, however, the disease flared up and hyperviscosity syndrome developed with epistaxis and retinal hemorrhage. He died of sepsis about 15 months after the initial diagnosis.
A direct ion chromatographic method of measuring carboxylic acids was modified and expanded to include measurement of eight components at parts-per-billion levels. These components, listed by eluting order, were acetate, propionate, formate, pyruvate, glyoxalate, dichloroacetate, oxalate and ketomalonate. The calculated method detection limits were 2-6 micrograms/l. Preliminary data were obtained by using California state project water from the filter influent of the Oxidation Demonstration Plant of the Metropolitan Water District of Southern California. Oxalate was measured at levels above 200 micrograms/l, formate above 100 micrograms/l, acetate above 50 micrograms/l, pyruvate and glyoxalate at approximately 30 micrograms/l and propionate and ketomalonate at trace levels near the detection limits. This method utilizes a new preservative, benzalkonium chloride, as a substitute for the environmentally unsafe mercuric chloride that had previously been used. Preservation studies indicate that all eight compounds are stable for a testing period of 30 days when benzalkonium chloride is maintained at or above 30 mg/l in the water sample.
Taichung is the largest city in the central part of Taiwan, and its air pollution problems are similar to those in other large cities around the world. To evaluate the potential of the air pollution and identify major pollutant sources in this city, 181 airborne particulate samples were collected biweekly from seven locations around Taichung over an entire year. The mutagenicity of acetone extracts of the air samples was evaluated using the Salmonella/microsomal test with Salmonella typhimurium TA98 in the presence and absence of S9 mixtures. The air samples from September 1994 showed the highest direct and indirect mutagenicity among the 12 months, whereas those from October and June had the lowest direct and indirect mutagenicity, respectively. To elucidate the correlation between mutagenicity and polycyclic aromatic hydrocarbons (PAHs), high-performance liquid chromatography was used to determine the amount of each of 10 PAHs in the air samples. Among the 10 PAHs, the monthly average amount of B[g,h,i]P in the samples was the highest, followed by B[a]FA, B[a]P, and B[k]FA. Linear regression analysis showed a positive correlation between monthly average total amounts of PAHs and indirect mutagenicity. The monthly average amount of B[g,h,i]P was correlated more with indirect mutagenicity than with other PAHs. B[g,h,i]P is an indicator PAH emitted from both diesel and gasoline engine exhaust. Thus, we suggest that mobile air pollutant sources in Taichung City may be more significant than stationary ones. Moreover, B[g,h,i]P seems to act as a mutagenicity indicator compound in air samples from Taichung City.
We tested the hypothesis that liquid ventilation (LV) with perfluorocarbon (PFC) can remove aspirated meconium and improve lung function in experimental meconium aspiration syndrome (MAS). PFC (FC-77) was used as the medium in LV. Sixteen piglets were divided into control and LV groups (8 animals/group). All animals received slurry meconium (20% in normal saline) via endotracheal instillation at baseline. Thirty minutes later, the LV group received 15 cycles of LV. Pulmonary mechanics, arterial blood gases, and hemodynamic values were recorded at baseline, and 30, 60, 120, 180, and 240 minutes after meconium instillation. Chest radiographs and lung sections were taken and scored at the end of the study. The percentage of meconium cleared by LV was calculated as the ratio of the dry weight of washings to that of meconium instilled, multiplied by 100. The procedure was tolerated well by the animals. LV cleared 25% +/- 7% of the instilled meconium. Tidal volume (9.5 +/- 2.0 vs 7.1 +/- 0.8 mL/kg, p = 0.012), respiratory system compliance (2.32 +/- 0.60 vs 1.60 +/- 0.24 mL/cmH2O, p = 0.01), PaO2 (65 +/- 7 torr vs 55 +/- 6 torr, p = 0.0067), and arterial to alveolar oxygen ratio (0.14 +/- 0.01 vs 0.12 +/- 0.01, p = 0.0077) were improved in the LV group at 60 minutes after meconium instillation compared with those of the control group. The scores of exudative debris (1.7 +/- 0.3 vs 2.1 +/- 0.2) and visible meconium (1.4 +/- 0.5 vs 2.1 +/- 0.5) were significantly lower in the LV group. In conclusion, short-term L.V with FC-77 can partially remove aspirated meconium from the lungs and improve pulmonary function transiently.