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Li-Tung Huang

Publications and source records attributed to Li-Tung Huang.

34 records · Page 2Linked to original sources

Neonatal bacterial meningitis in southern Taiwan.

To determine the epidemiologic trends, prognostic factors, and therapeutic results of neonatal bacterial meningitis, 60 neonatal patients with culture-proven neonatal bacterial meningitis were enrolled in this study. To compare changes over time, the appearance of disease among the patients was divided into two equal periods (1986-1993 and 1994-2001). Group B streptococci were the most common causative pathogens, accounting for approximately 32% of the episodes. Escherichia coli, the next most common pathogen, was more frequently observed in the second period. Seventy-seven percent of gram-negative bacilli isolates were resistant to ampicillin. Moreover, oxacillin-resistant Staphylococcus and ampicillin-resistant group B streptococci strains occurred in the second periods as late-onset neonatal bacterial meningitis. The overall mortality rates for the first and second study period were 17% and 8%, respectively. However, if individuals with poor outcomes were taken into account, 38% of patients were considered treatment failures. Significant prognostic factors included the presence of seizures, thrombocytopenia, and high cerebrospinal fluid protein and low cerebrospinal fluid glucose concentration. Although the mortality rate was significantly reduced in the second period, there has been increasing incidence of the emergence of resistant strains presenting a therapeutic challenge. The presentation in neonatal bacterial meningitis might be nonspecific, and blood culture results were negative in 45% of the episodes. Early diagnosis, choice of appropriate antibiotics, and correction of metabolic derangement are essential to improving outcomes.

Chi-Square Distribution↗

Long-term effects of status epilepticus in the immature brain are specific for age and model.

PURPOSE: Status epilepticus (SE) is more common in children than adults and has a high mortality and morbidity rate. SE in adult rats results in long-term disturbances in learning and memory, as well as an enhanced seizure susceptibility to further seizures. In contrast, a number of studies suggest that the immature brain is less vulnerable to the morphologic and physiologic alterations after SE. The goal of this study was to determine whether the long-term consequences of SE during development on hippocampal plasticity and cognitive function are age and model specific. METHODS: We used lithium-pilocarpine (Li-PC) to induce SE at different age points during development (P12, P16, P20) and evaluated the effects of this abnormal neural activity on spatial memory performance and seizure susceptibility in the animals beginning at P55, corresponding to young adulthood. RESULTS: We demonstrated that SE at P12 did not result in any structural or functional changes detectable in adulthood, whereas SE at both P16 and P20 induced cell loss and mossy fiber sprouting within the hippocampus and cognitive impairment when the animals were tested as adults. CONCLUSIONS: Whereas the seizure threshold to generalized seizures was not altered, animals with SE at P20 showed an increased susceptibility to kindling in adulthood.

Age Factors↗

Expression of CD40 ligand on CD4+ T-cells and platelets correlated to the coronary artery lesion and disease progress in Kawasaki disease.

OBJECTIVE: Kawasaki disease (KD) is an acute febrile vasculitic syndrome in children. CD40 ligand (CD40L) has been implicated in certain types of vasculitis. We proposed that CD40L expression might be correlated with coronary artery lesions in KD. METHODS: Blood samples were collected from 43 patients with KD before intravenous immunoglobulin (IVIG) treatment and 3 days afterward. Forty-three age-matched febrile children with various diseases were studied in parallel as controls. CD40L expression on T-cells and platelets were detected by flow cytometry, and soluble CD40L (sCD40L) levels were measured by enzyme-linked immunosorbent assay. RESULTS: We found that CD40L expression on CD4(+) T-cells was significantly higher in patients with KD than in the febrile control (FC) group (28.69 +/- 1.17% vs 4.37 +/- 0.36%). CD40L expression decreased significantly 3 days after IVIG administration (28.69 +/- 1.17% vs 13.53 +/- 0.55%). CD40L expression on platelets from patients with KD was also significantly higher than in the FC group (8.20 +/- 0.41% vs 1.26 +/- 0.12%) and decreased after IVIG therapy. sCD40L levels were also significantly higher in KD patients with those of FC (9.69 +/- 0.45 ng/mL vs 2.25 +/- 0.19 ng/mL) but were not affected by IVIG treatment 3 days afterward (9.69 +/- 0.45 ng/mL vs 9.03 +/- 0.32 ng/mL). More interesting, we found that in KD patients, CD40L expression on CD4(+) T-cells and platelets but not on CD8(+) T-cells or sCD40L was correlated with the occurrence of coronary artery lesions. CONCLUSIONS: CD40L might play a role in the immunopathogenesis of KD. IVIG therapy might downregulate CD40L expression, resulting in decrease of CD40L-mediated vascular damage in KD. This implicates that modulation of CD40L expression may benefit to treat KD vasculitis.

Acute Disease↗

Enhancement of CREBSerine-133 phosphorylation through nitric oxide-mediated signaling induced by bacterial lipopolysaccharide in vascular smooth muscle cells from rats.

Nitric oxide (NO) induced by bacterial lipopolysaccharide (LPS) plays a critical role in various patho-physiological implications, such as atherosclerosis, vasculitis and septic shock. In addition, cAMP-responsive element binding protein (CREB), an important transcription factor for cell differentiation, has been shown to be involved in atherosclerogenesis in VSMCs. Here we investigated the possibility whether LPS-induced NO signaling led to phosphorylation of cAMP-responsive element binding protein on Serine-133 (CREBSer-133) in cultured vascular smooth muscle cells (VSMCs) from rats. Addition of LPS (1-10 microg/ml) for 48 hours increased not only the production NO, but also the phosphorylation of CREBSer-133. The use of NOS inhibitor (100-500 microM L-NAME) blocked the magnitudes of both LPS-induced NO production and CREBSer-133 phosphorylation. In addition, either a guanylyl cyclase (GC) inhibitor (30 microM ODQ) or a cGMP-dependent protein kinase (PKG) inhibitor (20 microM (Rp)-8-pCPT-cGMPs) significantly attenuated the magnitudes of LPS-induced CREBSer-133 phosphorylation, suggesting the involvement of NO-GC-PKG signaling. Thus, the present study suggests that NO-mediated signaling activated by bacterial LPS, at least in part, enhance CREBSer-133 phosphorylation in cultured VSMCs. The findings here may provide not only signaling pathway involved in VSMC differentiation during inflammatory response, but also new insight into possible therapeutic intervention.

Animals↗

Aminophylline aggravates long-term morphological and cognitive damages in status epilepticus in immature rats.

Here, we investigated whether aminophylline, an adenosine receptor antagonist used usually as a treatment for premature apnea, had synergistic effects on status epilepticus in the developing brain. On postnatal day 14 (P14), four groups of rats intraperitoneally received saline, aminophylline, lithium--pilocarpine (Li-PC), and Li-PC plus aminophylline, respectively. Subsequently, the Morris water maze task was performed at P80. The brains were then analyzed with cresyl violet stain for histological lesions and evaluated for mossy fiber sprouting with the Timm stain. No seizures were elicited in the saline-treated or aminophylline-treated rats. Both the Li-PC-treated and aminophylline plus Li-PC-treated rats exhibited seizures and there was no significant difference in mortality between the two groups. More interestingly, as in adulthood (P80), aminophylline aggravated the spatial deficits and histological damages seen in Li-PC-treated rats. In summary, this present study suggests that the use of adenosine receptor antagonists, such as aminophylline, exacerbates seizure-induced damage in the developing brain.

Aging↗

Tuberculous meningitis in infancy.

The lack of specific symptoms and signs in patients with tuberculous meningitis makes early diagnosis difficult. To our knowledge, there has been no report in the literature focusing on tuberculous meningitis patients younger than 1 year of age. In this report, we reviewed the clinical features and laboratory findings of seven infants with tuberculous meningitis encountered during a 15-year period. All patients had fever, cough, and alternation of consciousness at presentation. Five patients had bulging anterior fontanel, and five had generalized tonic-clonic seizures. The purified protein derivative skin test was positive in six patients. Six patients had hyponatremia. All seven patients had abnormal cerebrospinal fluid findings, and six of them demonstrated cell counts less than 500 cells/mm(3) with lymphocytic predominance. Brain sonography examination revealed hydrocephalus in all seven patients. Therefore we conclude that antituberculosis therapy should be promptly initiated in any young infant with a clinical impression of meningitis in the context of cerebrospinal fluid white cell count of less than 500 cells/mm(3) and lymphocytic predominance, hyponatremia, and hydrocephalus.

Antitubercular Agents↗

Aminophylline exacerbates status epilepticus-induced neuronal damages in immature rats: a morphological, motor and behavioral study.

Adenosine is an endogenous modulator that has an inhibitory effect on neuronal activity. The aim of this work was to investigate the role of aminophylline, an adenosine receptor antagonist, on the long-term effects of status epilepticus (SE) in the developing brain. Four groups of rats at the postnatal age of 12 days were intraperitoneally administered with saline, aminophylline (50 mg/kg), lithium-pilocarpine (Li-PC) (3 mEq/kg-60 mg/kg), and Li-PC plus aminophylline, respectively. The four groups were tested for spatial memory using the Morris water maze task at P80 and motor performance by the Rotarod test at P100. The brains were then analyzed with cresyl violet stain for histological lesions and evaluated for mossy fiber sprouting with the Timm stain. At the acute stage, all rats subjected to Li-PC developed SE and no seizures were elicited in the saline-treated or aminophylline-treated rats. The seizure duration was longer in the Li-PC plus aminophylline group (346.9+/-32.7 min) as compared with that in the Li-PC group (265.2+/-9.8 min). The difference of mortality was not significant. Rats without seizures exhibited no motor imbalance, spatial deficits, or morphological changes. The rats with Li-PC-induced SE demonstrated spatial memory deficits without motor incoordination or morphological changes. However, the rats subjected to Li-PC plus aminophylline exhibited motor impairment and morphological changes, including neuronal cell loss in CA1 area and increased mossy fiber sprouting in CA3 area. In addition, the rats of Li-PC plus aminophylline had greater spatial memory deficits than that seen in rats with Li-PC. We concluded that an adenosine receptor antagonist, such as aminophylline, had synergistic effects on the SE-induced long-term deficit of cognition and motor performance in the developing brain. The present study may provide experimental evidence and lead to novel therapeutic interventions.

Aging↗

Maternal deprivation stress exacerbates cognitive deficits in immature rats with recurrent seizures.

PURPOSE: Maternal deprivation is stressful for the neonate. The aim of this study was to investigate the short- and long-term effects of maternal separation on recurrent seizures in the developing brain. METHODS: Rats were divided into four groups according to whether the rat pups were treated with maternal deprivation from postnatal day 2 (P2) to P9 or neonatal seizures induced by intraperitoneal (i.p.) injection of pentylenetetrazol (PTZ) from P10 to P14. Rats in the control group received saline i.p. injection from P10 to P14; rats in the isolation group underwent daily separation from their dams from P2 to P9; rats in the PTZ-treated group were subjected to PTZ-induced recurrent seizures from P10 to P14; rats in the isolation plus PTZ-treated group were subjected to maternal deprivation from P2 to P7 followed by serial seizures from P10 to P14. In addition, subsets of rats at P15 were killed and the brains assessed for acute neuronal degeneration. Visual-spatial memory test using the Morris water maze task was performed at P80. After testing, the hippocampus was evaluated for histologic lesions and cyclic adenosine monophosphate (cAMP)-responsive element-binding protein phosphorylation at serine-133 (pCREBSer-133), an important transcription factor underlying learning and memory. RESULTS: All rats given PTZ developed recurrent seizures. After PTZ administration, rats with a history of maternal deprivation had more intense impairment than did rats with maternal deprivation and neonatal seizures than those without deprivation. Neuronal degeneration was most prominent in the rats exposed to maternal deprivation plus recurrent seizures. Rats receiving maternal deprivation or PTZ-induced recurrent seizures exhibited only spatial deficits, but no morphologic changes in the hippocampus. However, rats with maternal deprivation plus PTZ-induced recurrent seizures exhibited worse visual-spatial learning compared with rats with either isolation or PTZ-induced recurrent seizures alone. The levels of pCREBSer-133 may play a role in the decrease in the hippocampus from the rats subjected to maternal deprivation and/or PTZ-induced recurrent seizures, as compared with rats exposed to vehicle-control saline. These results indicate that repeated maternal deprivation can exacerbate long-term cognitive deficits resulting from neonatal seizures. In addition, impaired phosphorylation of CREBSer-133. CONCLUSIONS: Repeated maternal deprivation stress has synergistic effects with recurrent seizures in inducing neurologic damage in the developing brain.

Animals↗

Pentylenetetrazol-induced recurrent seizures in rat pups: time course on spatial learning and long-term effects.

PURPOSE: Recurrent seizures in infants are associated with a high incidence of neurocognitive deficits. Animal models have suggested that the immature brain is less vulnerable to seizure-induced injury than is that in adult animals. We studied the effects of recurrent neonatal seizures on cognitive tasks performed when the animals were in adolescence and adulthood. METHODS: Seizures were induced by intraperitoneal injection of pentylenetetrazol (PTZ) for 5 consecutive days, starting from postnatal day 10 (P10). At P35 and P60, rats were tested for spatial memory by using the Morris water maze task. In adulthood, motor performance was examined by the Rotarod test, and activity level was assessed by the open field test. Seizure threshold was examined by inhalant flurothyl. To assess presence or absence of spontaneous seizures, rats were video recorded for 4 h/day for 10 consecutive days for the detection of spontaneous seizures. Finally, brains were examined for histologic evidence of injury with cresyl violet stain and Timm staining in the supragranular zone and CA3 pyramidal cell layers of the hippocampus. RESULTS: PTZ-treated rats showed significant spatial deficits in the Morris water maze at both P35 and P60. There were no differences in seizure threshold, motor balance, or activity level during the open field test. Spontaneous seizures were not recorded in any rat. The cresyl violet stain showed no cell loss in either the control or experimental rats. PTZ-treated rats exhibited more Timm staining in the CA3 subfield. However, the control and experimental rats showed similar Timm staining within the supragranular zone. CONCLUSIONS: Our findings indicate that recurrent PTZ-induced seizures result in long-term cognitive deficits and morphologic changes in the developing brain. Furthermore, these cognitive deficits could be detected during pubescence.

Age Factors↗

Decreased nitric oxide production after intravenous immunoglobulin treatment in patients with Kawasaki disease.

OBJECTIVE: To assess nitric oxide (NO) production and different displays of NO synthase (NOS) isoforms in patients with Kawasaki disease (KD) before and after intravenous immunoglobulin (IVIG) treatment. STUDY DESIGN: Blood and urine samples were collected from patients with KD before IVIG treatment and 3 days afterward. Age-matched febrile patients with various diseases served as control patients. Plasma NOx (NO3- + NO2-) levels were measured as NO production. Real-time reverse transcriptase-polymerase chain reaction and immunohistochemical staining were used to detect differential NOS isoform expression in mononuclear leukocytes (MNCs). RESULTS: Patients with KD (n = 40) had higher levels of NOx than the non-KD febrile control patients. The elevated NOx levels in patients with KD were significantly associated with the occurrence of coronary artery dilation (>3 mm). These elevated NOx levels significantly decreased after IVIG treatment (157.8 +/- 15.9 micromol/L vs 57.0 +/- 4.27 micromol/L, P <.01). However, excretion of urinary NOx levels was not changed after IVIG treatment. Inducible but not constitutive NOS mRNA and protein in MNCs were prominently expressed but significantly decreased after IVIG treatment. CONCLUSIONS: IVIG may suppress iNOS expression of MNCs in patients with KD, thus decreasing NO-mediated inflammatory responses and coronary artery dilation.

Child↗

Renal artery stenosis presenting with status epilepticus: a report of one case.

In children, renal artery stenosis is an uncommon but important cause of secondary hypertension. In this report, the authors describe a 5-year-old boy with no history of seizures who experienced status epilepticus. Postictal blood pressure, relative hypotension, was misinterpreted as normal on the day of admission. Two days later, his blood pressure rose gradually and peripheral plasma renin activity showed more than 1,700 micro U/mL. Magnetic resonance angiography suggested renal artery stenosis. After successful percutaneous transluminal angioplasty, the patient was seizure-free and had well-controlled blood pressure. This case describes renal artery stenosis present with status epilepticus, and emphasizes the importance of serial measurements of blood pressure in children.

Child, Preschool↗

Oral wooden stick injury complicated by meningitis and brain abscess.

Meningitis is rarely seen following oral injury. We describe a 3-year-old boy developing meningitis and brain abscess following a penetrating oral wooden stick injury. There was no cerebrospinal fluid rhinorrhea noted. A cerebrospinal fluid culture yielded viridans streptococcus. Brain magnetic resonance imaging and computed tomography revealed a multiloculated ring-enhancing mass. This patient underwent surgical drainage and completed 8-week antibiotic therapy. The patient demonstrated a late and dismal complication of a penetrating oral injury. At 2-year follow-up the patient was in good condition. A penetrating oral wooden stick inury should be regarded as potentially serious.

Brain Abscess↗

Liver abscess in children: a single institutional experience in southern Taiwan.

Liver abscess is uncommon in children. The purpose of this study is to evaluate the predisposing factors, pathogens, duration of hospitalization, and the managements of liver abscess in children. From 1986 to 2001, fifteen children were admitted to our hospital under the diagnosis of liver abscess. Thirteen cases were older than 8 years old and two were younger than one year old. Fever (15/15, 100%) and abdominal pain (13/15, 87%) were the most common symptoms. Twelve patients (80%) had prolonged fever (fever for 7 days or longer before diagnosis). Eleven (73%) cases were cryptogenic in origin. Most of the microorganisms were obtained solely from cultures of pus. Klebsiella pneumoniae was the most common organism isolated (6/15, 40%). Beside administration of antibiotics, percutaneous catheter drainage (PCD) was performed in 11 patients (73%); only one underwent surgical intervention due to poor response to PCD management. All of our patients were surviving after at least one year follow-up. In conclusion, liver abscess should be suspected in the patients with prolonged fever of unknown origin and abdominal pain. PCD combined with adequate antibiotics were sufficient for therapy of liver abscess in most cases. K. pneumoniae was the most common isolated pathogen in southern Taiwan.

Adolescent↗

Transient hyperammonemia in a neonate.

Neonatal hyperammonemia is a medical emergency requiring a multidisciplinary teamwork for early recognition and early treatment. The causes of neonatal hyperammonemia vary. The transient hyperammonemia of the neonate (THAN) occurs mostly in premature babies, and the prognosis is usually better than for urea cycle disorders. Here we present a near-term premature male infant with THAN. He exhibited the symptoms during the first 36 hours of life and survived after continuous arteriovenous hemodiafiltration (CAVHD). Nutritional support and sodium benzoate were also given. The diagnosis was based on laboratory tests. Long-term follow-up of neurodevelopment was suggested.

Anti-Infective Agents↗

Neonatal bacterial meningitis complicated with multiple brain abscesses and intraventricular rupture: report of one case.

Brain abscess is rarely encountered in neonates and carries a high morbidity and mortality. Here we report a premature infant who developed systemic Escherichia coli (E. coli) infection resulting in multiple brain abscesses with intraventricular rupture at 3 months postnatal age. He was treated successfully with a combination of surgical and antimicrobial therapies. Related literature on brain abscess with special emphasis on intraventricular rupture is reviewed.

Brain Abscess↗