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1.
Am J Perinatol ; 2021 Dec 07.
Article in English | MEDLINE | ID: mdl-34695864

ABSTRACT

OBJECTIVE: This study aimed to improve the utilization of amplitude-integrated electroencephalography (aEEG) in a neonatal unit by improving aEEG documentation, aEEG knowledge, and pattern recognition ability of neonatal staff. METHODS: A quality improvement (QI) program comprising the two Plan-Do-Study-Act (PDSA) cycles was conducted in a level-3 neonatal intensive care unit. The first cycle was focused on improving aEEG documentation with the primary outcome indicator being compliance with aEEG documentation. The second cycle was focused on aEEG interpretation in a health care professional education program with the outcome indicators being accuracy of seizure identification on aEEG and change in conventional EEGs (cEEG) performed. Other outcome indicators included accuracy in identification of background pattern, sleep-wake cycles and artifacts. Process indicators included improvement in aEEG-related knowledge. RESULTS: First PDSA cycle includes lectures on aEEG interpretation, a bedside key, and documentation form. Second PDSA cycle includes online aEEG education pack and detailed aEEG guideline. There was a significant improvement in aEEG documentation after the implementation of both PDSA cycles. Seven of the 46 patients (15.2%) had isolated electrographic seizures which would not have been identified in the pre-aEEG monitoring era. There was an increase in the number of patients with cEEGs done but a steady decrease in number of cEEGs per patient. CONCLUSION: With the successful application of standardized QI methods, improvements in outcome indicators, such as correct aEEG pattern recognition and improved coverage of at risk infants with cEEGs, were observed. Our QI measures were associated with improvement in aEEG pattern recognition. KEY POINTS: · Consistent and accurate use of aEEG is challenging.. · Standardized forms and guidelines improve aEEG interpretation consistency and documentation.. · Interactive self-paced online education packs can improve aEEG knowledge and pattern recognition..

2.
Arch Dis Child Fetal Neonatal Ed ; 101(1): F37-42, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26271752

ABSTRACT

SETTING: Neonatal end-of-life decisions could be influenced by cultural and ethnic backgrounds. These practices have been well described in the West but have not been systematically studied in an Asian population. OBJECTIVES: To determine: (1) different modes of neonatal death and changes over the past 12 years and (2) factors influencing end-of-life decision-making in Hong Kong. DESIGN: A retrospective study was conducted to review all death cases from 2002 to 2013 in the busiest neonatal unit in Hong Kong. Modes of death, demographical data, diagnoses, counselling and circumstances around the time of death, were collected and compared between groups. RESULTS: Of the 166 deaths, 46% occurred despite active resuscitation (group 1); 35% resulted from treatment withdrawal (group 2) and 19% occurred from withholding treatment (group 3). A rising trend towards treatment withdrawal was observed, from 20% to 47% over the 12-year period. Similar number of parents chose extubation (n=44, 27%) compared with other modalities of treatment limitation (n=45, 27%). Significantly more parents chose to withdraw rather than to withhold treatment if clinical conditions were 'stable' (p=0.03), whereas more parents chose withholding therapy if treatment was considered futile (p=0.03). CONCLUSION: In Hong Kong, a larger proportion of neonatal deaths occurred despite active resuscitation compared with Western data. Treatment withdrawal is, however, becoming increasingly more common. Unlike Western practice, similar percentages of parents chose other modalities of treatment limitation compared with direct extubation. Cultural variance could be a reason for the different end-of-life practice adopted in Hong Kong.


Subject(s)
Decision Making , Infant Mortality/trends , Terminal Care/trends , Withholding Treatment/trends , Cause of Death , Female , Hong Kong , Humans , Infant , Infant, Newborn , Male , Retrospective Studies
3.
Neonatology ; 105(4): 290-6, 2014.
Article in English | MEDLINE | ID: mdl-24576844

ABSTRACT

BACKGROUND: Infants receiving prolonged parenteral nutrition (PN) are at risk of PN-associated cholestasis (PNAC). This can progress to hepatic failure and death if PN cannot be discontinued. Fish oil-based parenteral lipid preparation (FOLP) has been shown to be beneficial in case studies. OBJECTIVES: (1) To evaluate whether FOLP could halt or reverse the progression of PNAC compared with soy-based parenteral lipid preparation (SLP) and (2) to assess the effects of FOLP on liver function and physical growth. DESIGN: double-blind randomised controlled trial. SETTING: level III neonatal intensive care unit. PARTICIPANTS: infants with PNAC (plasma-conjugated bilirubin concentration ≥ 34 µmol/l or 2 mg/dl) expected to be PN-dependent for >2 weeks. INTERVENTION: to receive either FOLP or SLP at 1.5 g/kg/day. PRIMARY OUTCOME MEASURE: reversal of PNAC within 4 months after commencement of lipid treatment; secondary outcomes: rate of change of weekly liver function tests, infant growth parameters, blood lipid profile and episodes of late-onset sepsis. RESULTS: A total of 9 infants were randomised to the FOLP group and 7 to the SLP group. There was no significant difference in reversal of PNAC at 4 months between groups. Rates of increase of plasma-conjugated bilirubin and alanine aminotransferase in the SLP group were significantly greater than the FOLP group (13.5 vs. 0.6 µmol/l per week and 9.1 vs. 1.1 IU/l per week, respectively, p = 0.03). Increased enteral nutrition was associated with significant improvement of PNAC in infants receiving FOLP compared with SLP (-8.5 vs. -1.6 µmol/l per 10% increase in enteral nutrition, respectively). The study was terminated prematurely. CONCLUSIONS: progression of PNAC in PN-dependent infants can be halted by replacing SLP with FOLP and reversed by increasing the proportion of enteral nutrition in infants receiving FOLP. Replacement of SLP with FOLP in PN-dependent infants who develop PNAC may be considered.


Subject(s)
Cholestasis/therapy , Fat Emulsions, Intravenous/administration & dosage , Fish Oils/administration & dosage , Parenteral Nutrition/adverse effects , Phospholipids/administration & dosage , Soybean Oil/administration & dosage , Alanine Transaminase/blood , Bilirubin/blood , Biomarkers/blood , Birth Weight , Child Development , Cholestasis/blood , Cholestasis/diagnosis , Cholestasis/etiology , Double-Blind Method , Early Termination of Clinical Trials , Emulsions/administration & dosage , Enteral Nutrition , Female , Gestational Age , Head/growth & development , Hong Kong , Humans , Infant , Infant Nutritional Physiological Phenomena , Infant, Low Birth Weight , Infant, Newborn , Infant, Premature , Intensive Care Units, Neonatal , Liver/metabolism , Male , Nutritional Status , Prospective Studies , Time Factors , Treatment Outcome , Triglycerides , Weight Gain
4.
Ann Surg ; 258(6): 1111-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23470582

ABSTRACT

OBJECTIVES: To evaluate the use of gut barrier proteins, liver-fatty acid binding protein (L-FABP), intestinal-fatty acid binding protein (I-FABP), and trefoil factor 3 (TFF3), as biomarkers for differentiating necrotizing enterocolitis (NEC) from septicemic/control infants and to identify the most severely affected surgical NEC from nonsurgical NEC infants. BACKGROUND: Clinical features and routine radiologic investigations have low diagnostic utilities in identifying surgical NEC patients. METHODS: The diagnostic utilities of individual biomarkers and the combination of biomarkers, the LIT score, were assessed among the NEC (n = 20), septicemia (n = 40), and control groups (n = 40) in a case-control study for the identification of proven NEC and surgical NEC infants. RESULTS: Plasma concentrations of all gut barrier biomarkers and the LIT score were significantly higher in the NEC than in the septicemia or control group (P < 0.01). Using median values of biomarkers and the LIT score in the NEC group as cutoff values for identifying NEC from septicemic/control cases, all had specificities of 95% or more and sensitivities of 50%. Significantly higher levels of biomarkers and the LIT score were found in infants with surgical NEC than in nonsurgical NEC cases (P ≤ 0.02). The median LIT score of 4.5 identified surgical NEC cases with sensitivity and specificity of 83% and 100%%, respectively. A high LIT score of 6 identified nonsurvivors of NEC with sensitivity and specificity of 78% and 91%, respectively. CONCLUSIONS: The LIT score can effectively differentiate surgical NEC from nonsurgical NEC infants and nonsurvivors of NEC from survivors at the onset of clinical presentation. Frontline neonatologists and surgeons may, therefore, target NEC infants who are most in need of close monitoring and those who may benefit from early surgical intervention.


Subject(s)
Enterocolitis, Necrotizing/blood , Enterocolitis, Necrotizing/diagnosis , Fatty Acid-Binding Proteins/blood , Infant, Premature, Diseases/blood , Infant, Premature, Diseases/diagnosis , Peptides/blood , Biomarkers/blood , Case-Control Studies , Diagnosis, Differential , Enterocolitis, Necrotizing/surgery , Female , Gastrointestinal Tract , Humans , Infant, Newborn , Infant, Premature , Infant, Premature, Diseases/surgery , Male , Sepsis/blood , Sepsis/diagnosis , Trefoil Factor-3
5.
BJOG ; 117(6): 765-7, 2010 May.
Article in English | MEDLINE | ID: mdl-20236106

ABSTRACT

Preterm delivery is the primary cause of neonatal mortality and morbidity worldwide. Labour at term occurs as a culmination of maturational events in both the fetus and maternal uterus. This process exhibits diurnal variation, with the onset of labour being more common at night. We have confirmed that this diurnal variation is present in gestations between 28 and 36 weeks, but is absent below 28 weeks. We hypothesise that this is because before 28 weeks of gestation, the onset of labour may result from a pathological rather than a physiological process. This may have important implications regarding any pharmacological approach to the prevention and/or treatment of very early preterm labour.


Subject(s)
Circadian Rhythm , Labor Onset/physiology , Obstetric Labor, Premature/etiology , Female , Humans , Obstetric Labor, Premature/physiopathology , Pregnancy , Pregnancy Trimester, Second/physiology , Pregnancy Trimester, Third/physiology
6.
Crit Care Med ; 37(8): 2441-7, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19531943

ABSTRACT

OBJECTIVE: To evaluate the usefulness of the Gram-specific probe-based quantitative polymerase chain reaction test for rapid detection and differentiation of Gram-negative and Gram-positive bacterial bloodstream infection in preterm infants. DESIGN: Cross-sectional study. SETTING: University-affiliated Level III neonatal intensive care unit. PATIENTS: Preterm infants with clinical features suggestive of late-onset infection. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: In addition to the full sepsis screen, 0.5 mL of EDTA blood was collected aseptically for Gram-specific quantitative polymerase chain reaction evaluation. The results were analyzed with respect to outcomes of bacterial culture in blood and other body fluids, including peritoneal and cerebrospinal fluids. The diagnostic utilities of the quantitative polymerase chain reaction were determined. A total of 218 suspected infection episodes were investigated, of which 42 episodes were culture positive and 176 were culture negative. For Gram-negative infection, the quantitative polymerase chain reaction test correctly identified 19 of 22 episodes, and the sensitivity and specificity were 86.4% and 99.0%, respectively. For Gram-positive infection, the test correctly identified 14/19 episodes, and the sensitivity and specificity were 73.7% and 98.5%. The remaining one episode was Candida albicans septicemia. None of the episodes with positive quantitative polymerase chain reaction test were classified into the wrong Gram stain category. More importantly, despite negative blood culture in five infants suffering from intra-abdominal sepsis (peritonitis [n = 4] and hepatosplenic abscess [n = 1]), the quantitative polymerase chain reaction test could detect the Gram-specific category of causative organisms in blood. CONCLUSIONS: The Gram-specific quantitative polymerase chain reaction test is reliable and highly specific for rapid identification and differentiation of Gram-negative and Gram-positive bloodstream and intra-abdominal infections. The result could be made available within 5 hrs after the specimen reaches the laboratory. A positive test is able to "rule in" bacterial bloodstream infection before blood culture results become available, and serves as a guide to predict the virulence of the causative organism according to its Gram-specific category so that critical patients can be targeted for intensive treatment.


Subject(s)
Bacteremia/diagnosis , Gram-Negative Bacterial Infections/diagnosis , Gram-Positive Bacterial Infections/diagnosis , Infant, Premature , Polymerase Chain Reaction/methods , Bacteremia/microbiology , Cross-Sectional Studies , Diagnosis, Differential , Female , Gram-Negative Bacterial Infections/microbiology , Gram-Positive Bacterial Infections/microbiology , Humans , Infant, Newborn , Male , Reproducibility of Results , Sensitivity and Specificity , Time Factors
7.
Clin Nutr ; 28(2): 209-12, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19261360

ABSTRACT

Four preterm infants with intestinal failure and severe parenteral nutrition-associated cholestasis (PNAC) received fish-oil-based parenteral lipid as rescue treatment in substitution for the standard soybean-based lipid preparation. The progression of liver disease was halted in 3 infants and they recovered with complete resolution of PNAC. The condition in two of these infants would almost certainly have progressed to end-stage hepatic failure if they had continued to receive long-term parenteral nutrition and <30% of total nutrition enterally. The remaining infant with residual inflamed bowel, protracted feeding intolerance and repeated episodes of sepsis did not respond. Our findings suggest that fish-oil-based parenteral lipid emulsion may contribute to effective treatment of PNAC in selected patients, which should be further evaluated in randomized controlled trials.


Subject(s)
Cholestasis/therapy , Fat Emulsions, Intravenous/therapeutic use , Fish Oils/therapeutic use , Infant, Premature, Diseases/therapy , Intestinal Diseases/therapy , Lipids/therapeutic use , Parenteral Nutrition/methods , Cholestasis/etiology , Fatal Outcome , Humans , Infant , Infant, Newborn , Infant, Premature , Liver Failure/etiology , Liver Failure/prevention & control , Male , Parenteral Nutrition/adverse effects , Treatment Outcome
8.
J Phys Chem B ; 109(19): 9575-80, 2005 May 19.
Article in English | MEDLINE | ID: mdl-16852152

ABSTRACT

During template-assisted electrodeposition, single-crystalline metallic nanowires could be obtained only when the overpotential is low. However, an unusual electrodeposition behavior on the PAA/Si substrate without a conductive interlayer between the template and Si is described in the present study. Through the electrical breakdown of the template, Ni nanodots, nanowires and nanotubes could be obtained by only changing the electrodeposition voltage on the same substrate. The mechanisms leading to the formation of various nanostructures are described in detail and compared with those for the conventional template-assisted electrodeposition process. The electrodeposition first occurred on the pore wall instead of from the underlying substrate, leading to the formation of some Ni nanotubes at a more negative voltage. Besides, single-crystalline Ni nanowires could also be formed even when the electrodeposition voltage was as negative as -40 V, indicating that the formation of single-crystalline metallic nanowires under a large overpotential is possible.

9.
Pediatrics ; 112(4): e254, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14523207

ABSTRACT

Severe acute respiratory syndrome (SARS) is a newly discovered infectious disease caused by a novel coronavirus. During the community outbreak in Hong Kong, 5 liveborn infants were born to pregnant women with SARS. A systematic search for perinatal transmission of the SARS-associated coronavirus, including serial reverse transcriptase-polymerase chain reaction assays, viral cultures, and paired serologic titers, failed to detect the virus in any of the infants. In addition, none of the infants developed clinical, radiologic, hematologic, or biochemical evidence suggestive of SARS. One preterm infant developed jejunal perforation and another developed necrotizing enterocolitis with ileal perforation shortly after birth. This case series is the first report to describe the clinical course of the first cohort of liveborn infants born to pregnant women with SARS.


Subject(s)
Infectious Disease Transmission, Vertical , Pregnancy Complications, Infectious/virology , Severe Acute Respiratory Syndrome/transmission , Adult , Anti-Inflammatory Agents/adverse effects , Anti-Inflammatory Agents/therapeutic use , Antiviral Agents/adverse effects , Antiviral Agents/therapeutic use , Cesarean Section , Cohort Studies , Disease Outbreaks , Enterocolitis, Necrotizing/etiology , Female , Fetal Growth Retardation/etiology , Hong Kong/epidemiology , Humans , Ileal Diseases/etiology , Infant, Newborn , Infant, Premature , Intestinal Perforation/etiology , Jejunal Diseases/etiology , Male , Methylprednisolone/adverse effects , Methylprednisolone/therapeutic use , Pregnancy , Pregnancy Complications, Infectious/drug therapy , Pregnancy Complications, Infectious/epidemiology , Respiratory Distress Syndrome, Newborn/complications , Ribavirin/adverse effects , Ribavirin/therapeutic use , Severe acute respiratory syndrome-related coronavirus/isolation & purification , Severe Acute Respiratory Syndrome/drug therapy , Severe Acute Respiratory Syndrome/epidemiology
10.
Acta Orthop Scand ; 73(6): 658-62, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12553513

ABSTRACT

We studied the expression of procollagen type I, matrix metalloproteinase 1 (MMP1) and tissue inhibitor of metalloproteinase 1 (TIMP-1) by immunohistochemistry in human patellar tendinosis tissues and healthy patellar tendons. In situ gelatin zymography was used to detect collagenolytic activities. The productions of MMP1, TIMP1 and gelatinolytic activities were compared in cell cultures from tendinosis samples and controls. Tendinosis tissues and cultures showed an increase in the expression level of MMP1 and a decrease in that of TIMP1, a condition favoring collagen degradation. Gelatinolytic activities in tendinosis tissues and cultures were elevated. Collagenolysis is a striking feature in patellar tendinosis.


Subject(s)
Matrix Metalloproteinase 1/analysis , Patella/pathology , Tendinopathy/pathology , Tendons/pathology , Adolescent , Adult , Collagen Type I/analysis , Female , Humans , Male , Patella/physiopathology , Protease Inhibitors/analysis , Tendinopathy/physiopathology , Tendons/physiopathology , Tissue Inhibitor of Metalloproteinase-1/analysis
12.
Genes Dev ; 15(9): 1140-51, 2001 May 01.
Article in English | MEDLINE | ID: mdl-11331609

ABSTRACT

A yeast two-hybrid screen using the conserved carboxyl terminus of the nuclear receptor corepressor SMRT as a bait led to the isolation of a novel human gene termed SHARP (SMRT/HDAC1 Associated Repressor Protein). SHARP is a potent transcriptional repressor whose repression domain (RD) interacts directly with SMRT and at least five members of the NuRD complex including HDAC1 and HDAC2. In addition, SHARP binds to the steroid receptor RNA coactivator SRA via an intrinsic RNA binding domain and suppresses SRA-potentiated steroid receptor transcription activity. Accordingly, SHARP has the capacity to modulate both liganded and nonliganded nuclear receptors. Surprisingly, the expression of SHARP is itself steroid inducible, suggesting a simple feedback mechanism for attenuation of the hormonal response.


Subject(s)
DNA-Binding Proteins/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Repressor Proteins/genetics , Repressor Proteins/metabolism , Amino Acid Motifs , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , Conserved Sequence , DNA-Binding Proteins/genetics , Estrogens/metabolism , Histone Deacetylase 1 , Histone Deacetylase 2 , Histone Deacetylases/genetics , Histone Deacetylases/metabolism , Humans , Mice , Molecular Sequence Data , Nuclear Receptor Co-Repressor 2 , RNA, Long Noncoding , RNA, Untranslated , Receptors, Estrogen/metabolism
13.
Clin Imaging ; 24(2): 64-7, 2000.
Article in English | MEDLINE | ID: mdl-11124472

ABSTRACT

Xanthogranulomatosis is an idiopathic, rare process in which lipid-laden histiocytes may deposit in various locations in the body, which if systemic is called Erdheim-Chester disease. A rare case of isolated retroperitoneal, bilateral perinephric xanthogranulomatosis is reported. The diagnosis was suspected on cross-sectional imaging and was confirmed by CT-guided percutaneous core biopsy.


Subject(s)
Biopsy/methods , Histiocytosis, Non-Langerhans-Cell/diagnostic imaging , Retroperitoneal Space/diagnostic imaging , Tomography, X-Ray Computed , Aged , Diagnosis, Differential , Histiocytosis, Non-Langerhans-Cell/pathology , Humans , Male , Retroperitoneal Space/pathology
14.
Clin Nucl Med ; 24(10): 781-3, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10512105

ABSTRACT

PURPOSE: To assess the use of a Tc-99m erythrocyte-labeled SPECT scan to characterize a giant splenic hemangioma. METHODS: A patient clinically mistaken to have a myelodysplastic disorder underwent a contrast-enhanced CT followed by a Tc-99m erythrocyte-labeled SPECT scan. RESULTS: CT showed a heterogeneous vascular lesion arising in the spleen. Percutaneous biopsy was nondiagnostic. A Tc-99m erythrocyte-labeled SPECT study revealed findings consistent with a giant splenic hemangioma, which was subsequently confirmed at surgery. CONCLUSION: A Tc-99m erythrocyte-labeled SPECT scan may be very useful in confirming the diagnosis of a large or giant splenic hemangioma.

15.
J Vasc Surg ; 29(4): 719-21, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10194502

ABSTRACT

Splenic vein aneurysms are rare and are usually caused by portal hypertension. Symptoms are unusual, but may include rupture or abdominal pain. Diagnosis can usually be made either by means of duplex ultrasonography or computed tomography scanning. Treatment varies from noninvasive follow-up to aneurysm excision. We report an expanding splenic vein aneurysm in a young woman with abdominal and back pain and no history of portal hypertension. She was treated with aneurysm excision and splenectomy.


Subject(s)
Aneurysm/surgery , Splenic Vein , Abdominal Pain/etiology , Aneurysm/complications , Aneurysm/diagnosis , Female , Humans , Middle Aged , Splenic Vein/diagnostic imaging , Splenic Vein/surgery , Tomography, X-Ray Computed
16.
J Virol ; 73(2): 1239-44, 1999 Feb.
Article in English | MEDLINE | ID: mdl-9882327

ABSTRACT

A double mutation which converts nucleotide 1765 from A to T and nucleotide 1767 from G to A is frequently found in the hepatitis B virus (HBV) genome isolated from HBV patients with chronic hepatitis symptoms. This double mutation is located in the core promoter that controls the transcription of the precore RNA and the core RNA. In addition, this double mutation also resides in the X protein coding sequence, converting codon 130 from Lys to Met and codon 131 from Val to Ile. Previous studies indicate that this double mutation removes a nuclear receptor binding site in the core promoter, suppresses specifically precore RNA transcription, and enhances viral replication. In this study, we further investigated how this double mutation suppresses precore RNA transcription. We found that this double mutation not only removed the nuclear receptor binding site but also created an HNF1 transcription factor binding site. Further transfection studies using Huh7 hepatoma cells indicate that the removal of the nuclear receptor binding site has no effect on the transcription of HBV RNAs, the two-codon change in the X protein sequence suppresses the transcription of both precore and core RNAs, and the creation of the HNF1 binding site restores the core RNA level. Hence, the specific suppression of precore RNA transcription by this frequent double-nucleotide mutation is the combined result of multiple factors.


Subject(s)
DNA-Binding Proteins , Gene Expression Regulation, Viral , Hepatitis B Core Antigens/genetics , Hepatitis B virus/genetics , Mutation , Protein Precursors/genetics , RNA, Viral , Binding Sites , Cell Nucleus/metabolism , Hepatitis B, Chronic/virology , Hepatocyte Nuclear Factor 1 , Hepatocyte Nuclear Factor 1-alpha , Hepatocyte Nuclear Factor 1-beta , Humans , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Promoter Regions, Genetic , Receptors, Virus/metabolism , Trans-Activators/genetics , Trans-Activators/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Transcription, Genetic , Tumor Cells, Cultured , Viral Regulatory and Accessory Proteins
17.
J Mater Sci Mater Med ; 9(5): 297-300, 1998 May.
Article in English | MEDLINE | ID: mdl-15348888

ABSTRACT

Modification of ethyl alcohol added aqueous electrolyte for depositing calcium phosphate on titanium substrates by a electrocrystallization method is described. Film coated in the electrolyte with ethyl alcohol addition is more homogeneous and the growth rate is higher. The optimum quantity of ethyl alcohol added is 50% of the electrolyte. Although the pH value of electrolyte varies as ethyl alcohol is added, the phases of the deposited film remain the same, and are hydroxyapatite and brushite. The development of the microstructure of the coated film during deposition is discussed.

18.
Biomaterials ; 17(21): 2059-64, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8902238

ABSTRACT

Four different temperatures (700-1000 degrees C) were chosen for calcination treatment of as-received hydroxyapatite powder before press forming and sintering to study the effect of calcination on the sintering behaviours. The results show that calcination treatment increases the average particle size and distribution, which changes from trimodal to monomodal. The sintering behaviours were investigated by dilatometry and density measurement. Fluidity of powder and driving force for sintering were found to dominate the properties. Calcining at 900 degrees C and sintering 1250 degrees C results in a higher bending strength (about 55 MPa) with finer grain size.


Subject(s)
Hydroxyapatites , Hot Temperature , Particle Size , Physical Phenomena , Physics , Powders
19.
Diagn Cytopathol ; 14(3): 268-72, 1996 May.
Article in English | MEDLINE | ID: mdl-8732660

ABSTRACT

Cytologic detection of lung cancer is accepted, accurate, and time-honored. Typically, cytologic workup of a radiologic abnormality proceeds sequentially from sputum to bronchoalveolar cytology, and, if necessary, to fine-needle aspiration biopsy (FNA). Initial use of FNA in lung cancer diagnosis is controversial, but increasingly popular. We therefore decided to objectively assess current practice in cytologic lung cancer diagnosis at our institution. All pulmonary cytologic diagnoses for 1993 and the first half of 1994 were retrieved. Positive diagnoses were then used to access all patient data. Patients were stratified according to the specimen from which the first positive diagnosis was obtained. Of 542 pulmonary cytology specimens, 15% were sputa, 65% were bronchoalveolar, and 20% were FNAs. One hundred sixty-one of 172 malignant diagnoses were first diagnoses. Three percent of first malignant diagnoses were made from sputa, 47% were from lavages, and 50% were from FNAs. Although FNAs comprised just 20% of all pulmonary cytologies, 50% of all new malignant cytologic diagnoses were made by FNA. Initial use of FNA is successful, has a high diagnostic yield and low complication rate, and offers the most direct approach to diagnosis.


Subject(s)
Biopsy, Needle , Lung Neoplasms/diagnosis , Biopsy, Needle/adverse effects , Humans , Pneumothorax/etiology , Tomography, X-Ray Computed
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