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Biomedical subjects

K S Lee

Publications and source records attributed to K S Lee.

At least 37 records · Page 2Linked to original sources

Massive intracerebral air embolism associated with meningitis and lumbar spondylitis: case report.

BACKGROUND: Massive intracerebral air embolism is a rare pathologic state and never in association with meningitis and lumbar spondylitis. To the best of our knowledge, our presented case is the first of a massive intracerebral air embolism associated with meningitis and lumbar spondylitis of Klebsiella pneumonia. CASE DESCRIPTION: A 55-year-old man presented with a high fever and low back pain. Blood culture showed Klebsiella pneumonia. Lumbar computed tomography (CT) revealed discitis at L1-2 and L2-3 levels and paraspinal abscess in which air was found. Despite management with antibiotics, patient's consciousness deteriorated, and brain CT revealed diffuse intravenous air embolism and severe brain swelling. Cerebrospinal fluid (CSF) examination demonstrated bacterial meningitis, and the CSF culture showed Klebsiella pneumonia. Later, septic shock occurred and patient expired. CONCLUSION: Intracerebral air embolism can occur in the Klebsiella pneumonia meningitis that resulted from lumbar spondylitis and sepsis.

Cerebral Veins↗

A pilot study of cytoreductive chemotherapy combined with infusion of additional peripheral blood stem cells reserved at time of harvest for transplantation in case of relapsed hematologic malignancies after allogeneic peripheral blood stem cell transplant.

Reharvesting leukocytes from donors for a donor leukocyte infusion (DLI) is inconvenient and occasionally impossible in case of unrelated donors. It is well known that the effect of a growth factor-primed DLI is comparable to that of a nonprimed DLI. In total, 42 patients with hematologic malignancies and a high risk of relapse were allocated, on an intent-to-treat basis, a peripheral blood stem cell transplantation (PBSCT) from HLA-matched sibling donors, and then at the time of harvest, additional peripheral blood stem cells (PBSCs) were also reserved for a therapeutic primed DLI in case of relapse. In all, 12 patients who relapsed after allogeneic PBSCT were treated with mainly cytarabine-based chemotherapy followed by a cryopreserved PBSC infusion. The median dose of CD3+ and CD34+ cells for the primed DLIs was 1.43 x 10(8)/kg and 4.75 x 10(6)/kg, respectively. Six of the 12 relapsed patients exhibited a complete response after the primed DLI, plus their 1-year survival rate was 33%. The new development or progression of graft-versus-host disease after a primed DLI was observed in 50% of the patients. Overall, the survival at 1 year was 16.7%. Accordingly, the induction of a graft-versus-leukemia effect through a primed DLI, using additional PBSCs reserved at the original time of harvest, would appear to be feasible for patients with relapsed hematologic malignancies. Furthermore, this approach is also more convenient for donors.

Adoptive Transfer↗

Clinical impact of hyperacute graft-versus-host disease on results of allogeneic stem cell transplantation.

The current study defines the incidence and clinical manifestations of hyperacute graft-versus-host disease (haGVHD; fever, skin rash, diarrhea, and hepatic dysfunction) and analyzes the risk factor and the impact of haGVHD on the results of allogeneic stem cell transplantation (SCT). In all, 90 patients underwent allogeneic SCT from 71 matched siblings or 19 alternative donors. Immediate high-dose steroids were administered to 22 patients who met the criteria. The overall incidence of haGVHD was 36.7% (n=34) and haGVHD was also strongly correlated with acute (aGVHD) (P<0.001) and extensive chronic GVHD (cGVHD) (P=0.007), and found to be associated with decreased probability of relapse (P=0.0017). Early intervention with steroids within 7 days after the diagnosis of haGVHD might be associated with better survival. A survival analysis of the overall survival and disease-free survival did not reveal any difference between haGVHD+ and haGVHD- groups. In multivariate analysis, the use of an alternative donor (P=0.020) was identified as the only risk factor. Immediate high-dose steroids were effective in treating haGVHD. We conclude that in an allogeneic setting, haGVHD is not an uncommon manifestation, associated with the development of aGVHD or cGVHD. The only risk factor for haGVHD was the use of an alternative donor.

Adrenal Cortex Hormones↗

Risk factors for late cytomegalovirus infection after allogeneic stem cell transplantation using HLA-matched sibling donor: donor lymphocyte infusion and previous history of early CMV infection.

An increased incidence of late cytomegalovirus (CMV) infection has been reported during the last decade since the introduction of ganciclovir (GCV) prophylaxis or GCV pre-emptive therapy. Given that a donor lymphocyte infusion (DLI) can induce more severe GVHD, this may predispose a patient to late CMV infection. In all, 64 patients (median age 36, M/F 38/26) underwent allogeneic stem cell transplantation (SCT) using a matched sibling donor with bone marrow (n=9) or peripheral blood stem cells (n=55). The overall incidence of CMV infection, early and late CMV infection was 46.9 (30/64), 42.2 (27/64), and 16.4% (9/55), respectively. Early CMV infection was treated with GCV pre-emptive therapy that produced a 92.6% success rate. Among the 20 patients who received 35 DLIs, late CMV infection developed in eight (42.1%) of 19 evaluable cases with a median onset at 127 days post transplant. Risk factors for late CMV infection in a logistic regression analysis included DLIs (P=0.001) and a previous history of CMV infection (P=0.006). In conclusion, late CMV infection was strongly associated with DLIs and a previous history of early CMV infection. Accordingly, extended surveillance of CMV antigenemia is recommended for patients receiving DLIs or who have a previous history of CMV infection.

Adult↗

Transplantation outcome in allogeneic PBSCT patients according to a new chronic GVHD grading system, including extensive skin involvement, thrombocytopenia, and progressive-type onset.

Patients who had suffered chronic GVHD after an allogeneic PBSCT were evaluated using a new chronic GVHD grading system. The study included 36 consecutive adult patients with hematological diseases, who survived at least until day 90 following allogeneic PBSCT and who could be evaluated for chronic GVHD. Extensive skin involvement was observed in five patients, thrombocytopenia in 14, and progressive-type onset in 10, while grade 1 chronic GVHD appeared in 21 patients, grade 2 in 10, and grade 3 in five. There was a significant difference in the probability of relapse between the groups with grade 1 and 2+3 chronic GVHD (55.3 vs 16.4%, P=0.0211). The difference was particularly marked in patients with high-risk hematological malignancies (grade 1 vs grade 2+3, 75 vs 0%, P=0.0115). With a median follow-up of 12 months (range, 4-52 months), 22 (66.1%) patients were still alive. The estimated 2-year survival rate for the whole population was 57.6%, while that for the group with chronic GVHD grade 1 and grade 2+3 was 53.5 and 56.3%, respectively (P=0.4387). Accordingly, there was a significant difference in the probability of relapse between the groups with grade 1 and grade 2+3 chronic GVHD.

Adolescent↗

A phase II trial of capecitabine in previously untreated patients with advanced and/or metastatic gastric cancer.

BACKGROUND: Capecitabine (Xeloda) is a novel, oral, selectively tumor-activated fluoropyrimidine with proven activity in the treatment of advanced colorectal cancer. This trial was conducted to evaluate the efficacy, safety and feasibility of capecitabine in previously untreated patients with advanced and/or metastatic gastric cancer, with a view to replacing 5-fluorouracil (5-FU) in such patients. PATIENTS AND METHODS: Forty-four patients received capecitabine 1250 mg/m2 twice daily (2500 mg/m2/day) for 14 days followed by 7 days of rest, for up to six cycles. RESULTS: Capecitabine produced an objective response rate of 34% (all partial responses) and stable disease in 14 patients (30%). The median time to disease progression (TTP) was 3.2 months [95% confidence interval (CI) 2.7-6.4 months] and median overall survival was 9.5 months (95% CI 6.9-13.2 months). Hand-foot syndrome (HFS), nausea, anorexia, diarrhea and vomiting were the most common adverse events. While HFS was the most frequent grade 3/4 toxicity (National Cancer Institute Common Toxicity Criteria), only 9% of patients experienced grade 3 HFS. Severe myelosuppression was not reported during the study. CONCLUSIONS: Capecitabine monotherapy is active and well tolerated as first-line therapy in patients with advanced/metastatic gastric cancer. Larger comparative trials investigating capecitabine-based combination regimens in patients with advanced gastric cancer are warranted.

Administration, Oral↗

Imbalance between matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in toluene diisocyanate-induced asthma.

BACKGROUND: Toluene diisocyanate (TDI)-induced asthma is an inflammatory disease of the airways characterized by airway remodelling due, at least in part, to an excess of extracellular matrix deposition in the airway wall. The ratio of matrix metalloproteinase-9 (MMP-9) and its inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1) may be a marker of the balance between airway tissue destruction and repair. OBJECTIVE: We determined whether an imbalance of the MMP-9 : TIMP-1 molar ratio is present before and/or after challenge with TDI. METHODS: We used a murine model of TDI-induced asthma to evaluate the MMP-9 and TIMP-1 balance in the lung. RESULTS: The expression of MMP-9 and TIMP-1 mRNAs and proteins in the lungs increased at 7 h after TDI inhalation and continued for up to 72 h. Immunohistochemical and immunocytological analyses in the lungs of TDI-exposed mice revealed increases of immunoreactive MMP-9 and TIMP-1. There were significant correlations between the levels of MMP-9 or TIMP-1 and the number of neutrophils, lymphocytes, or eosinophils. The molar ratio of MMP-9/TIMP-1 significantly decreased at 7 h after TDI inhalation and continued up to 72 h. CONCLUSION: These data suggest that TDI-induced asthma may be associated with an imbalance between MMP-9 and TIMP-1, which could be useful as a marker of airway inflammation and airway remodelling in this disease.

Animals↗

A field comparison of four samplers for enumerating fungal aerosols I. Sampling characteristics.

UNLABELLED: This study compared the performance of four bioaerosol samplers, the Reuter Centrifugal Air Sampler, the Andersen N6 single stage, the Surface Air System 90, and the Air-o-Cell, in measurements for airborne fungal propagules collected in 75 public building sites without prior knowledge of water damage or mold problems in British Columbia, Canada. The samplers had differences in detection limits, reproducibility, and overall yield. However, high and significant correlations between samplers (indoor samples: Pearson r = 0.60-0.85, P < 0.001) suggest that relative performances between samplers were reasonably consistent. These results indicate that fungal airborne concentration data are dependent on the methods used for assessment, and introduce additional variability in exposure assessment studies. PRACTICAL IMPLICATIONS: In the absence of a standard protocol for sampling bioaerosols, the interpretation of aerosol data reported in indoor air quality studies is entirely dependent on an appreciation of the sampling characteristics of commonly used instrumentation. Although a number of comparative studies have been undertaken in the laboratory, only a few studies have made reported comparison data under field conditions. This study compared three culturable sampling devices, the Andersen N6, SAS 90, and RCS, and one particulate sampling device, the Air-o-Cell, in offices and public areas in a variety of buildings, under conditions of forced air or natural ventilation. The concentrations of fungal aerosols collected during simultaneous sample collection were highly correlated, yet varied by orders of magnitude. The performance of these devices must be carefully considered before a standard protocol can be promulgated.

Air Microbiology↗

A field comparison of four fungal aerosol sampling instruments: inter-sampler calibrations and caveats.

UNLABELLED: Four bioaerosol samplers (Reuter Centrifugal, Andersen N6 Single Stage, Surface Air System Super 90, and Air-o-Cell) were used to take c. 300 side-by-side measurements at 75 public building sites. Regression models were developed to examine the relationships between each method pair. The models demonstrate that measurements from these instruments are not directly comparable, requiring inter-instrument calibration. Sampling location (indoor vs. outdoor) was a confounder in all the pairwise comparisons between samplers. In addition, the slopes of the relationships between all method pairs except one differed in indoor vs. outdoor locations. These results emphasize that direct comparisons between methods should not be undergone without prior calibration. Where measurement circumstances are similar to those of this study, the regression models might serve as a basis to convert measurements made with one instrument to those made with another. However, the robustness and generalizability of the models in different measurement settings needs to be assessed. PRACTICAL IMPLICATIONS: Many different bioaerosol sampling devices are in common use for indoor air quality studies. If data from research studies are to be compared, an approximation of the relationships between the equipment would be useful. A comparison of three culturable sampling devices (Andersen N6, SAS 90, RCS) and one particulate sampling device (Air-o-Cell) collecting simultaneous samples under field conditions showed high linear correlations between methods. However, while direct comparisons between sampling data were not possible, the regression models reported here explained 60-85% of the variance in fungal concentrations, and underscored the importance of the effect of environment on measurement.

Air Microbiology↗

Previously-treated nasopharyngeal carcinoma with cystic lesions in the temporal lobe.

Nasopharyngeal carcinoma is a common malignancy in the Asian Chinese population. First-line treatment consists primarily of radiotherapy and chemotherapy, with salvage surgery if recurrence occurs. Patients with this tumours frequently present years after radiotherapy with symptomatic temporal lobe cystic lesions and a diagnostic problem arises. The possible differential diagnoses include radionecrosis, pyogenic abscesses or tumour recurrence. A series of three cases of cystic temporal lobe lesions, with emphasis on their clinical, radiological and histopathological diagnostic aspects, are presented. The three cases presented consist of radiation necrosis, pyogenic abscess, and a case with both infection with tumour recurrence. The methodology of both clinical and radiological diagnosis are presented.

Adult↗

Topographical anatomy on the communicating branch between the spinal accessory nerve and the anterior root of the first cervical nerve.

The aim of this study was to clarify the morphological characteristics of the communicating branch between the spinal accessory nerve and the anterior root of the first cervical nerve (McKenzie branch), a structure severed during intradural selective rhizotomy for treatment of spasmodic torticollis. The right and left sides of 50 upper cervical segments of spinal cords were dissected and examined under a surgical microscope. Seven of the total 100 samples were found to have the McKenzie branch. Two types of McKenzie branch, which run close to the vertebral artery, were also identified, which might be helpful for improving the surgical results of intradural selective rhizotomy.

Accessory Nerve↗

The conditional probabilities of survival in patients with anaplastic astrocytoma or glioblastoma multiforme.

BACKGROUND: By the use of conditional probabilities of survival, we studied the yearly survival rates for individual tumor survivors. METHODS: Conditional survival rate was estimated in 114 consecutive patients with anaplastic astrocytoma or glioblastoma multiforme. Conditional probabilities of surviving some years given survival to a specific period of time after craniotomy and 95% confidence intervals were calculated in the individual tumor survivors. RESULTS: The estimated median survival was 30 months for 45 patients with anaplastic astrocytoma and 12 months for 69 patients with glioblastoma multiforme. The conditional probabilities of surviving next one year given survival to 1 year, 2 years, 3 years, 4 years, or 5 years after craniotomy for anaplastic astrocytoma were 86.2%, 75.0%, 85.9%, 77.8%, or 85.7%, respectively; for glioblastoma multiforme 64.8%, 58.7%, 85.7%, 80.0%, or 75.0%, respectively. The conditional probability of surviving to 5 years given survival to 2 years after craniotomy for anaplastic astrocytoma, i.e., surviving an additional 3 years, was 50.1%, which was better than observed 5-year survival rate (28.6%); for glioblastoma multiforme it was 40.2%, which also was better than observed 5-year survival rate (12.4%). CONCLUSIONS: The conditional probability of survival was a good method to clinically predict yearly survival rate for individual tumor survivors. In addition, the method can estimate the probabilities of surviving next some years given survival to a specific period of time after craniotomy. It also showed a more encouraging result than observed survival rate in patients with supratentorial malignant astrocytomas.

Adult↗

Perceived long-term prognosis of teeth with orthodontically resorbed roots.

OBJECTIVES: To investigate the perceived significance of root resorption in the dental community. STUDY DESIGN AND SAMPLE: Mail out survey questionnaire accompanied by morphed images of 10-50% root resorption. General practitioners, periodontists, prosthodontists and orthodontists were the participants. OUTCOME MEASURES: Correlations between 'significant' and 'detrimental to the longevity of the tooth'. These assessments were conducted within specialty groups and among. Also measured was the source of knowledge upon which practitioner assessments were based. RESULTS AND CONCLUSIONS: General practitioners were the most concerned about root resorption. Although most practitioners feel 50% root resorption is significant and detrimental to the longevity of the tooth, extraction followed by prosthetic replacement was not an option. No agreement among practitioners when orthodontic treatment should be terminated; the general practitioners were conservative suggesting termination after 35% root loss. History of trauma, genetic disposition and root morphology are the most cited predisposing factors. Lengthy treatment time concerns general practitioners more than the orthodontists. With the exception of orthodontists, dentists believe excessive force is detrimental to the root, but no one is able to define what excessive force is. Overall, dental school curricula overstate the causes of root resorption. Generally, dental professionals seem to base their opinions on myths and are largely inconsistent in their assessments.

Attitude of Health Personnel↗

Denitrification and phosphorus release under anoxic conditions in an anoxic-anaerobic-aerobic BNR process.

An anoxic-anaerobic-aerobic biologial nutrient removal process was used in this study. The kinetic aspects of denitrification and phosphorus release under anoxic conditions were investigated by conducting a pilot-scale plant operation under various SRTs (solids retention times), HRTs (hydraulic retention times) and internal recycle ratios. The process was capable of completely denitrifying the NOx- -N (the sum of NO2- -N and NO3- -N) in the nitrified recycle, resulting in an NOx- -N concentration of less than 1.0 mg l(-1) N in the anoxic zones. Denitrification and phosphorus release were accomplished due to abundant organic substrates in the anoxic zone at the head end of the process and achieved approximately equivalent rates with respect to influent SCOD loading in the zone. Phosphorus release continued without any nitrate inhibition due to low NOx- -N concentrations of less than 2.0 mg l(-1) N in the anaerobic zone.

Bacteria, Aerobic↗

Diagnostic criteria for the clinical syndrome of internal disc disruption: are they reliable?

A new disease, named internal disc disruption (IDD), has provoked debate. Some insist that discography is specific for the diagnosis, while others disagree. Without scientific verification, some doctors have performed invasive operations for this uncertain disease. It is necessary to explore the diagnostic criteria and characteristics of IDD. We investigated the background, history, diagnostic methods and criteria of IDD by a review of the literature. The criteria for diagnosis of IDD are diverse. The minimum requirements for the diagnosis were the pattern of pain and the shape on discography. Although the pain pattern is important for the correct diagnosis, it depends on the subjective report of the patient. The diagnosis is up to the patient, and the examiner alone cannot make it. We conclude that IDD is not a real, but a hypothetical disease. Until scientific verification is forthcoming any invasive procedures should be restricted.

Diagnostic Techniques, Neurological↗

Socioeconomic and state-level differences in prenatal diagnosis and live birth prevalence of Down's syndrome in the United States.

BACKGROUND: Previous studies have shown socioeconomic disparities in the use of prenatal diagnosis in several countries, including France and the United States. Few studies however, have examined the impact of socioeconomic differences in prenatal testing on disparities in the live birth prevalence of congenital anomalies. In this article, we first review and further discuss some of the results of our previously published work that assesses: i) socioeconomic differences in the use of amniocentesis in the United States using data from national birth cohorts; and ii) impact of socioeconomic differences in prenatal diagnosis on the live birth prevalence of Down's syndrome (trisomy 21). We then present the results of a study that explores the potential effects of public policies regarding abortion on state-level differences in the live birth prevalence of Down's syndrome. MATERIALS AND METHODS: We used birth data from the National Center for Health Statistics for the years 1989 to 1991 as well as data from the National Abortion and Reproductive Rights Action League (NARAL) state-by-state review of abortion rights. The main individual-level socioeconomic variables in the analyses were maternal ethnicity and education; the analyses of the interaction effects between maternal age and ethnicity are presented here. Interaction effects were assessed using logistic regression models with likelihood ratio tests. We used hierarchical logistic regression models for analyses of state-level effects while controlling for individual-level socioeconomic factors. RESULTS: We found substantial age-specific socioeconomic differences in the use of amniocentesis and in the rates of age-related increase in the live birth prevalence of Down's syndrome. In particular, African Americans and Mexican Americans were found to have lower odds of amniocentesis use and higher odds of Down's syndrome at birth. In addition, after controlling for maternal age, socioeconomic factors and prenatal care, we found that states which allowed public financing of abortion services for all or most circumstances had lower odds of Down's syndrome at birth. CONCLUSION: Unless socioeconomic differences in prenatal testing are addressed, the increasing use of prenatal testing might result in widening socioeconomic disparities in the live birth prevalence of Down's syndrome and other major congenital anomalies in future years.

Abortion, Induced↗