A 915-MHz antenna for microwave thermal ablation treatment: physical design, computer modeling and experimental measurement

A 915-MHz antenna design that produces specific absorption rate distributions with preferential power deposition in tissues surrounding and including the distal end of the catheter antenna is described. The design features minimal reflected microwave current from the antenna flowing up the transmission line. This cap-choke antenna consists of an annular cap and a coaxial choke which matches the antenna to the coaxial transmission line. The design minimizes heating of the coaxial cable and its performance is not affected by the depth of insertion of the antenna into tissue. The paper provides a comparison of results obtained from computer modeling and experimental measurements made in tissue equivalent phantom materials. There is excellent agreement between numerical modeling and experimental measurement. The cap-choke, matched-dipole type antenna is suitable for intracavitary microwave thermal ablation therapy.

Deficiency of the specific granule proteins, R-binder/transcobalamin I and lactoferrin, in plasma and saliva: a new disorder

The mechanisms of hereditary deficiency of R binder, which originates in neutrophils and exocrine gland epithelium, are unknown and may be multiple. This led us to examine if defective R binder synthesis also involves proteins that colocalize with it in neutrophil-specific granules and exocrine epithelial cells and may be under common regulatory control. Stored plasma and saliva samples from five unrelated R binder-deficient patients and control subjects were assayed for R binder, lactoferrin, cationic antimicrobial protein-18, neutrophil gelatinase-associated lipocalin, gelatinase, lysozyme, and myeloperoxidase. One patient, patient A, had lactoferrin levels below the limits of detection in both plasma and saliva in addition to his R binder deficiency. Although his deficiency involved lactoferrin as well, he had no history of predisposition to infection. PCR amplification of his R binder gene promoter region and the beginning of the first exon revealed no DNA abnormalities. His son and the son of his equally deficient brother, both presumptive heterozygotes, had mild deficiency of both R binder and lactoferrin. The results show that R binder deficiency exists in at least two forms. One, presumably the less common of the two forms, is the new hereditary entity described here, which is characterized by deficiency of more than one specific granule protein in both plasma and saliva. Despite this more widely distributed absence of the proteins than is found in congenital specific granule deficiency, infection posed no clinical problem in the affected patient.

In vitro and in vivo studies for modified ethyl cyanoacrylate regimens for sclerotherapy

Cyanoacrylates have known for their ability to polymerize rapidly in the presence of traces of weakly basic moieties such as water. The tissue adhesive, Histoacryl(R) (N-butyl 2-cyanoacrylate), has been reported to control bleeding through endoscopic sclerotherapy. But the commercially available Histoacryl(R) is expensive, and it has the problem like other cyanoacrylates that the glue tends to flow/run away from the point of application, which is inherent to the low viscosity, making precise application difficult. In this study, ethyl cyanoacrylate (ECA), the main constituent of "super glue," was employed instead of Histoacryl(R) due to its lower cost. The aim of the research is to modify the compositions of ECA regimen and evaluate its feasibility for sclerosant application through both in vitro flow circuit model and in vivo animal tests. It was noted that the difference in the relative hardening rate between the in vitro Hepes-Tyrodes buffer flowing model and the in vivo rat model for the ECA and Histoacryl(R) was related to the existence of the blood protein, such as albumin, in the physiological milieu. It was also noticed that the ECA setting rate was greatly increased either in Hepes-Tyrodes buffer or in blood (to a comparable rate as Histoacryl(R) in vivo) by adding a few doses of caffeine, which acts as a polymerization initiator. This would lead to far better injection precision during sclerotherapy. Furthermore, in vivo histological examination for the occluded lumen of the rat's inferior vena cava and a clinical piglet portal vein occlusion experiment have suggested this new sclerosant regimen, caffeine/ECA, is of great promise in endoscopic sclerotherapy.

Surface characterization and platelet adhesion studies on fluorocarbons prepared by plasma-induced graft polymerization

It is believed that the interactions between the biological environment and biomaterial surface are the key factors influencing its biocompatibility. Therefore, plasma processing, which can vary the surface properties without altering the bulk properties, has been considered as one of the important techniques for improving a materials' biocompatibility. In this investigation, plasma-induced grafting polymerization of vinylidene fluoride (VDF) and chlorotrifluoroethylene (CTFE), instead of direct plasma polymerization, was attempted with an aim to improve the substrate blood compatibility. Contact angle measurement indicated both fluorocarbon-grafted Pdyethylenes (PEs) are hydrophobic. Due to the additional fluorine and chlorine atoms on the CTFE chain, the PCTFE-grafted PE exhibited a higher hydrophobicity than the PVDF-grafted one. ESCA analysis has revealed that these two plasma-induced fluorocarbon deposits contain almost no CFx (x > 2) binding on the surface layer, indicating the grafting polymerization mainly follows the free radical mechanism instead of the molecule-highly-fragmented reaction steps commonly seen in the direct plasma polymerization treatment. In addition, ATR-FTIR has shown the surface chemical configuration of these PVDF- and PCTFE-grafted PEs to be very similar to those of the bulk samples of PVDF and PCTFE. The surface roughness decreased after oxygen plasma treatment and was further reduced by VDF and CTFE grafting polymerization. In vitro platelet adhesion testing indicated these two fluorocarbon grafted PEs are less platelet-activating than the nontreated PE control and oxygen plasma activated one.

Functional mutation in the promoter region of thrombomodulin gene in relation to carotid atherosclerosis

Thrombomodulin is an important endothelial anticoagulant protein that decreases thrombin activity and activates protein C. Our recent study has shown that the G-33A promoter mutation of thrombomodulin gene is associated with coronary artery disease. This study was conducted to determine whether the G-33A mutation in the promoter region of thrombomodulin gene is a genetic risk factor for ischemic stroke or carotid atherosclerosis. The functional significance of this mutation was also evaluated. We recruited 333 patients (mean age 64 years, 59% male) with ischemic stroke and 257 age- and sex-matched controls. In all study participants, carotid atherosclerosis was assessed by Duplex scanning, and thrombomodulin G-33A promoter mutation was detected by single-strand conformation polymorphism. Luciferase reporter gene assay was used to assess the influence of this mutation on thrombomodulin promoter activity. There was no significant difference in the thrombomodulin G-33A mutation frequency (GA+AA genotypes) between the stroke and the control groups (18.3 vs. 24. 1%, P=0.105). The G-33A mutation frequency was also similar between the study participants with and without carotid atherosclerosis (22.2 vs. 19.8%, P=0.550). When only younger subjects (age </=60 years) were included in the analysis, however, we found the mutation occurred more frequently in participants with carotid atherosclerosis (33.3 vs. 17.3%, odds ratio [OR]=2.38, 95% confidence interval [CI]=1.16-4.90, P=0.027). Multiple logistic regression analyses showed that only diabetes mellitus (OR=3.11, 95% CI=1.33-7.30, P=0.009) and G-33A mutation (OR=2.46, 95% CI=1.14-5.29, P=0.021) were associated independently with carotid atherosclerosis in younger subjects. As assessed by luciferase reporter gene assays, the contructs bearing the G-33A mutation showed a significant decrease (36+/-12%) in transcriptional activity in comparison with the wild type constructs. Our findings suggest that G-33A mutation reduces the thrombomodulin promoter activity and is associated with carotid atherosclerosis in younger subjects.

Excess mortality due to pneumonia or influenza during influenza seasons among persons with acquired immunodeficiency syndrome

BACKGROUND

Anecdotal reports suggest that influenza-related morbidity may be high among persons with acquired immunodeficiency syndrome (AIDS), but little information is available concerning the population-level impact of influenza on mortality in persons with AIDS.

METHODS

Using the Multiple Cause-of-Death data files, which contain information on all deaths occurring in the United States each year, we calculated the numbers of excess deaths and rates of excess death due to pneumonia or influenza among persons with AIDS aged 13 years and older during the influenza seasons 1991-1992 through 1993-1994. For comparison, numbers of excess deaths and excess death rates were also calculated for several other groups including the general US population aged 13 years and older and the general US population aged 65 years and older.

RESULTS

During the 1991-1992, 1992-1993, and 1993-1994 influenza seasons, there were 261, 254, and 191 excess deaths due to pneumonia or influenza in persons with AIDS and excess death rates of 19.74, 15.38, and 10.17 deaths per 10 000 persons, respectively, compared with a summer baseline period. For the same seasons, we observed excess death rates of 1.40, 1.62, and 1.48 for the general US population aged 13 years and older and 8.10, 9.28, and 8.54 for the general US population aged 65 years and older. Thus, persons with AIDS had excess death rates substantially higher than the general US population and similar to, if not somewhat higher than, the general US population aged 65 years and older, a group that is already targeted for annual vaccination. The findings were similar when we compared the preinfluenza season with the influenza season.

CONCLUSIONS

Persons with AIDS have significant excess mortality due to pneumonia or influenza during influenza seasons and should be considered a high-risk group that is targeted for the prevention of influenza.

The external granule layer of the developing chick cerebellum generates granule cells and cells of the isthmus and rostral hindbrain

The external granule layer (EGL) on the dorsal surface of the developing cerebellum consists of neural progenitors originating from the rostral rhombic lip (RRL). The RRL and the EGL were thought to give rise exclusively to the granule neurons of the cerebellum (Alder et al., 1996). To study the fate of individual RRL cells, we used a retroviral library to mark clones in the chick embryo at Hamberger-Hamilton stages 10-12. RRL clones comprised the EGL and cerebellar granule cells, as expected. Surprisingly, however, as many as 50% of the RRL clones also contained cells ventral to the cerebellum proper. Ventral derivatives were found in clones with a medial origin, as well as in those with a lateral origin along the RRL. Some of the ventral progeny appeared to be in the process of migration, whereas others appeared to be differentiating neurons in the isthmus and the rostral hindbrain region, including the locus coeruleus (LC) and pontine reticular formation. Furthermore, the Phox2a marker of LC precursors was detected in the EGL within the anterior aspect of the cerebellum. A stream of cells originating in the EGL and expressing Phox2a was observed to terminate ventrally in the LC. These data demonstrate that single RRL progenitor cells are not restricted to producing only cerebellar granule cells; they produce both cerebellar granule cells and ventral derivatives, some of which become hindbrain neurons. They also suggest that some progeny of the EGL escape the cerebellum via the anterior aspect of the cerebellar peduncles, to contribute to the generation of ventral structures such as the LC.

In vivo assessment of trabecular bone structure using fractal analysis of distal radius radiographs

Our purpose in this study was (i) to measure trabecular bone structure using fractal analysis of distal radius radiographs in subjects with and without osteoporotic hip fractures, and (ii) to compare these measures with bone mineral density (BMD) as well as with measures of trabecular bone structure derived from high resolution magnetic resonance (MR) images. Distal radius radiographs were obtained using semi-industrial films (55 kVp, 400 mAs) in 30 postmenopausal patients, who had suffered osteoporotic hip fractures (74.8+/-8.2 years) in the last 24 months and 27 postmenopausal age-matched (74.6+/-6.6 yr) normal volunteers. Radiographs were digitized at 50 microm. A Fourier power spectrum-based fractal dimension (FD) characterizing the trabecular pattern was measured in a region of interest proximal to the joint line. The fractal dimension was calculated over two spatial frequency (f) ranges: FD1 was calculated over 0.5<log(f)<l.0, FD2 over the higher range 1.0<log(f)<1.5. Trabecular BMD in the radius was obtained using peripheral quantitative computed tomography (pQCT) (Stratec GmbH, Germany). In addition BMD of the proximal femur was determined using dual x-ray absorptiometry (DXA) (QDR 2000, Hologic, MA). In a subset of patients (16 controls and 18 with hip fractures), high resolution MR imaging of the distal radius (spatial resolution of 156 x 156 x 500 microm) was used to obtain measures analogous to bone histomorphometry. There were significant differences (p<0.05) between the fracture and nonfracture groups in the total femur BMD (13%), trabecular BMD in the distal radius (4%), and the fractal dimension in the radiographs (FD2) (3%). The correlations between FD2 and the total femur BMD as well as trabecular bone BMD in the distal radius were -0.48 (p<0.006) and -0.22 (p<0.33); respectively; FD1 increased with BMD and showed lower correlations. FD2 showed good correlations with App. Tb.N (-0.71) and App. Tb.Sp (0.69) (p<0.01), moderate correlation with App BV/TV (-0.53) (p<0.05), and no significant correlation with App. Tb.Th. The correlations between structural measures and FD1 showed the inverse trend and were typically lower. The odds ratios for a hip fracture were 2.44 for total femur BMD, 1.5 for trabecular BMD (radius), and 1.5 for FD2, respectively. In summary, the fractal measures derived from radiographs of the radius show differences between subjects with and without hip fractures, the predictive power of measures in the distal radius are comparable to radial trabecular BMD but lower than that of total hip BMD.

Extensive posterior-lateral tracheal laceration complicating percutaneous dilational tracheostomy

BACKGROUND

An extensive posterior-lateral longitudinal tracheal laceration is an uncommon but serious complication of percutaneous dilational tracheostomy (PDT). We report the successful management of three ventilator-dependent patients whose percutaneous tracheostomy was complicated by an extensive longitudinal posterior-lateral tracheal laceration requiring operative repair.

METHODS

A retrospective review of 134 cases of PDT with concurrent bronchoscopy was performed between April 1997 and July 1999 and compared with a review of 124 cases of open tracheostomy. Tracheal lacerations were primarily repaired and augmented with intercostal muscle pedicle buttress.

RESULTS

Three cases of an extensive posterior-lateral longitudinal tracheal laceration that required operative repair were reported in the PDT group. None were reported in the open tracheostomy group. The 3 patients were managed with an adult high-frequency oscillating ventilator or pressure control ventilation during the postoperative period to limit barotrauma, and all healed without evidence of tracheal leak or stenosis.

CONCLUSIONS

The increasing popularity of PDT, particularly among nonsurgical disciplines, may generate an increasing number of complications requiring operative attention. Thoracic surgeons need to be cognizant of the pitfalls of PDT technique and be prepared to manage these difficult clinical scenarios.

Evaluation of graft patency during minimally invasive coronary artery bypass grafting with Doppler flow analysis

BACKGROUND

An objective method for determining intraoperative graft patency is an essential part of minimally invasive direct coronary artery bypass. This study compares angiography and Doppler methods for graft analysis during minimally invasive direct coronary artery bypass and presents long-term outcome in a cohort of patients.

METHODS

Between March and October 1997, 35 patients had elective minimally invasive direct coronary artery bypass procedures in which the left internal mammary artery was anastomosed to the left anterior descending coronary artery. Immediate graft patency was determined with intraoperative angiography using selective injection of the left internal mammary artery from a femoral approach and with Doppler flow analysis using a 1-mm, 20-MHz Doppler probe placed directly on the graft.

RESULTS

There was immediate perfect patency with brisk flow in 91% of patients (32 of 35). A normal Doppler study, defined as a diastolic predominant pattern with a diastolic flow velocity of greater than 15 cm/second, was found in all patients with normal angiograms. All patients with abnormal angiograms also had abnormal Doppler flow. Thus, Doppler analysis was 100% accurate for confirming graft patency and for detecting failed grafts. All abnormal grafts were successfully revised, which allowed 100% early patency. Operative mortality was 2.8% (1 of 35) and there have been no late deaths at a follow-up of more than 2 years. One patient required angioplasty of the anastomosis (1 of 34, 2.9%), but none have required subsequent surgical intervention.

CONCLUSIONS

Objective analysis of graft flow in the operating room is necessary to achieve 100% early graft patency with minimally invasive direct coronary artery bypass operations. Doppler analysis is the preferred initial method, because it is safe, accurate, and rapid.

Video-assisted thoracic surgery for diseases within the mediastinum

VATS and concepts of minimal access thoracic surgery have revitalized many aspects of general thoracic surgery, including the surgical approach to diseases and conditions of the mediastinum. Proven surgical options that have been shunned by patients and referring physicians because of the perceived morbidity of thoracotomy have been reconsidered with the emergence of these minimal access surgical options. Continued critical review of the accumulating experience in VATS techniques will refine the surgical indications for VATS and open thoracotomy.

Synthesis, surface characterization, and platelet reactivity evaluation for the self-assembled monolayer of alkanethiol with sulfonic acid functionality

Owing to the capability of fabricating a well-defined chemical structure on the surface, self-assembled alkanethiols with a variety of terminal functionalities were prepared on the gold substrate for investigating the interactions between the biological environment and synthetic surface. In this study, we report the synthesis of the sulfonic acid terminated long-chain alkanethiol, 10-mercaptodecane-sulfonic acid, for direct preparation of a self-assembled monolayer (SAM) with -SO(3)H functionality. Nuclear magnetic resonance (NMR) and elemental analysis studies indicated that a high purity of sulfonic acid terminated alkanethiol was obtained. Surface characterization results showed that the -SO(3)H terminated SAM is hydrophilic and has a slightly higher hysteresis value, possibly because of the slower chain mobility of the bound sulfonic acid alkanethiol. Electron spectroscopy for chemical analysis (ESCA) analysis demonstrated that the -SO(3)H terminal group is situated in the outermost layer of the monolayer, as previous alkanethiol SAM structure models proposed. The platelet reactivity of the -SO(3)H SAM was higher than that of -OH SAM but less than the -CH(3) terminated one in vitro, whereas similar platelet reactivity was noticed between the -SO(3)H and -COOH SAMs. The higher platelet reactivity found on the -SO(3)H SAM could be caused by the higher surface functional group density inherent in the SAM structure and/or the composition and conformation state of the adsorbed protein layer.

Phlebotomy overdraw in the neonatal intensive care nursery

OBJECTIVE

Because blood loss attributable to laboratory testing is the primary cause of anemia among preterm infants during the first weeks of life, we quantified blood lost attributable to phlebotomy overdraw, ie, excess that might be avoided. We hypothesized that phlebotomy overdraw in excess of that requested by the hospital laboratory was a common occurrence, that clinical factors associated with excessive phlebotomy loss would be identified, and that some of these factors are potentially correctable. DESIGN, OUTCOME MEASURES, AND ANALYSIS: Blood samples drawn for clinical purposes from neonates cared for in our 2 neonatal special care units were weighed, and selected clinical data were recorded. The latter included the test performed; the blood collection container used; the infant's location (ie, neonatal intensive care unit [NICU] and intermediate intensive care unit); the infant's weight at sampling; and the phlebotomist's level of experience, work shift, and clinical role. Data were analyzed by univariate and multivariate procedures. Phlebotomists included laboratory technicians stationed in the neonatal satellite laboratory, phlebotomists assigned to the hospital's central laboratory, and neonatal staff nurses. Phlebotomists were considered experienced if they had worked in the nursery setting for >1 year. Blood was sampled from a venous or arterial catheter or by capillary stick from a finger or heel. Blood collection containers were classified as tubes with marked fill-lines imprinted on the outside wall, tubes without fill-lines, and syringes. Infants were classified by weight into 3 groups: <1 kg, 1 to 2 kg, and >2 kg. The volume of blood removed was calculated by subtracting the weight of the empty collection container from that of the container filled with blood and dividing by the specific gravity of blood, ie, 1.050 g/mL. The volume of blood withdrawn for individual laboratory tests was expressed as a percentage of the volume requested by the hospital laboratory.

RESULTS

The mean (+/- standard error of the mean) volume of blood drawn for the 578 tests drawn exceeded that requested by the hospital laboratory by 19.0% +/- 1.8% per test. The clinical factors identified as being significantly associated with greater phlebotomy overdraw in the multiple regression model included: 1) collection in blood containers without fill-lines; 2) lighter weight infants; and 3) critically ill infants being cared for in the NICU. Because the overall R(2) of the multiple regression for these 3 clinical factors was only.24, the random factor of individual phlebotomist was added to the model. This model showed that there was a significant variation in blood overdraw among individual phlebotomists, and as a result, the overall R(2) increased to.52. An additional subset analysis involving 2 of the 3 groups of blood drawers (ie, hospital and neonatal laboratory phlebotomists) examining the effect of work shift, demonstrated that there was significantly greater overdraw for blood samples obtained during the evening shift, compared with the day shift when drawn using unmarked tubes for the group of heavier infants cared for in the NICU.

CONCLUSION

Significant volumes of blood loss are attributable to overdraw for laboratory testing. This occurrence likely exacerbates the anemia of prematurity and may increase the need for transfusions in some infants. Attempts should be made to correct the factors involved. Common sense suggests that blood samples drawn in tubes with fill-lines marked on the outside would more closely approximate the volumes requested than those without. Conversely, the use of unmarked tubes could lead to phlebotomy overdraw because phlebotomists may overcompensate to avoid having to redraw the sample because of an insufficient volume for analysis. We were surprised to observe that the lightest and most critically ill infants experienced the greatest blood overdraw. (ABSTRACT TRUNCATED)

Ethanol potentiates dopamine release during acute hypoxia in rat striatum

We, and others, have previously demonstrated that N-methyl-D-aspartate (NMDA) receptor is involved in hypoxia or ischemia-mediated responses. We found that the NMDA antagonist ketamine attenuates cortical nitric oxide release during cerebroischemia. It has been reported that ethanol (EtOH) antagonizes NMDA-induced responses in various systems. In the present study, the interaction of EtOH and KCl-evoked striatal dopamine release in vivo during acute hypoxia was examined. High-speed chronoamperometric recording techniques, using Nafion-coated carbon fiber electrodes, were used to evaluate extracellular dopamine (DA) concentration in the striatum of urethane-anesthetized Sprague-Dawley rats. KCl was directly applied to the striatum to evoke release of DA. These anesthetized animals were paralyzed with d-tubocurarine and connected to a respirator to allow controlled respiration. Systemic concentrations of oxygen were altered by changing the rate of the respirator. We previously reported that lowering the respiratory rates from 90 to 20 times/min for 5 min decreased arterial PO(2) and facilitated KCl-induced DA release in the striatum. In this study, we found that application of NMDA antagonist MK801 attenuates hypoxic DA release, suggesting that NMDA receptor is involved in this hypoxic reaction. In contrast, EtOH dose dependently enhanced KCl-evoked DA release during hypoxia. To further examine the interactions of excitatory amino acid and EtOH on DA release, glutamate was locally applied to the striatum. Glutamate-induced DA release was not affected by the systemic application of EtOH. Taken together, these data suggest that EtOH enhances DA release in vivo during short-term hypoxia, possibly through mechanisms other than excitatory amino acid pathways.

Parkinsonism as an initial manifestation of brain tumor

Parkinsonism secondary to neoplasm is uncommon. We report two patients with bilaterally symmetric parkinsonism as the initial presentation of their brain tumors. The first patient was a 71-year-old woman who presented with a gradual onset of bilateral resting tremor, bradykinesia and rigidity. Computerized tomography (CT) of the brain revealed a large parasagittal tumor in the left frontal lobe. The patient completely recovered from the parkinsonian symptoms after removal of the brain tumor. The second patient, a 74-year-old man with a history of renal cell carcinoma of the right kidney suffered from an insidious onset of bilateral bradykinesia, rigidity and gait difficulty. Cerebral metastasis was noted on the brain CT scan. Early recognition of intracranial tumor as the cause of parkinsonism is important for the management of this type of movement disorder. Moreover, brain CT scanning plays an important role in the differential diagnosis of patients with parkinsonian symptoms.

The development of human exposure standards for radio-frequency fields

Biological effects and health implications of radio frequency (RF) electromagnetic fields have been a subject of scientific investigation for more than 50 years. It has become a focus of attention because of the expanded use of RF radiation in the frequency range between 300 MHz and 6 GHz for wireless communication over the past decade. Another cause for the attention is the uncertainty of some observed responses and lack of understanding of the mechanism of interaction of RF electromagnetic fields with biological systems. At present, considerable efforts are devoted to developing and revising RF exposure standards. Each of these efforts should aim to make explicit the philosophy and process by which they reason and decide guidelines for deeming exposure as safe. Furthermore, the reconciliation of philosophies of protection will definitely be an asset, in practice, to those interested in international harmonization of RF exposure standards.

The central mechanism of hypothalamic-pituitary-adrenocortical system hyperfunction in depressed patients

While hypercortisolemia is commonly observed in depression, exactly where in the hypothalamic-pituitary-adrenocortical (H-P-A) axis this dysfunction arises remains undefined. In attempting to distinguish between central or peripheral locus of dysfunction, we studied in 12 patients (10 females, two males) with primary major depression and eight age-matched controls (six females, two males) in their adrenal cortisol response to infused adrenocorticotropic hormone (ACTH) (cosyntropin 0.05 microg/kg bodyweight) while endogenous ACTH was suppressed with 1 mg of dexamethasone. Compared with the control group, pre-dexamethasone plasma baseline cortisol level was significantly higher in depressed patients while ACTH level remained normal. Post-dexamethasone responses of both hormones were greatly non-suppressed in the depressed group. Exogenous cosyntropin-elicited rise in plasma cortisol was significantly lower in depressed patients while the ACTH response was not significantly different. These findings suggest that an adrenal cortisol response to ACTH was significantly decreased during depression as compared with normals in Chinese depressed patients. Therefore, the central mechanism of hyperfunctioning H-P-A axis causing hypercortisolemia should be emphasized.

Transcriptional regulatory effects of lymphoma-associated NFKB2/lyt10 protooncogenes

C-terminal truncations of the NFKB2 p100 gene product have been observed in a number of cases of human cutaneous T cell lymphomas, as well as human B-cell lymphomas and myelomas. The contribution of these alterations to lymphomagenesis is not understood; however, truncation at amino acid 666 to generate 80 - 85 kD proteins in the HUT78 cell line is associated with addition of a short (serine-alanine-serine) fusion at the 3' end of p80HT, as well as with increased expression of NFKB2 mRNA. We therefore examined the effects of p80HT on the regulation of NFKB2 expression, as well as the properties of a series of other tumor-associated, and site directed mutations of NFKB2. While p80HT had not itself acquired novel transcriptional activation properties with respect to the NFKB2 P1 or P2 promoters or the IL-6 kappaB promoter, p80HT had lost the potent inhibitory (IkappaB-like) activity associated with the wild-type, p100 gene product. Loss of the inhibitory property depended on the SAS residues in the fusion protein, direct truncation at aa666 was fully inhibitory, as was a substitution of three alanines for the SAS residues. The presence of as few as two C-terminal ankyrin motifs was sufficient for inhibition of NF-kappaB-mediated transcriptional activation. Assays of a series of additional lymphoma-associated NF-kappaB-2 truncation suggested that the C-terminal truncation associated with these proteins was also associated with a loss of the IkappaB-like activities of p100 NF-kappaB-2, for at least some NF-kappaB target promoters. Thus, the loss of IkappaB-like activity of lymphoma-associated NFKB2 mutations may play an important role in the genesis of a subset of human lymphomas.

Chlamydia pneumoniae infection in community-acquired pneumonia in Taiwan

Chlamydia pneumoniae is a common cause of pneumonia worldwide. This study examined the role of C. pneumoniae in 229 patients with community-acquired pneumonia. The ages of the patients ranged from 2 to 95 years. Sera were assayed for IgM and IgG antibodies with microimmunofluorescence (MIF). An IgM titer equal to or greater than 1:20 and IgG titer equal to or greater than 1:64 were considered positive. The prevalence of positive IgG among all of the patients was 75.1% (172/229). The seroprevalence was 81.8% (9/11) for patients in the 11- to 20-year-old group, 63.6% (14/22) in the 31- to 40-year-old group and 88.1% (52/59) in the 71- to 80-year-old group. All patients had a negative result for IgM antibody. Twenty-five of the patients had an IgG titer equal to or greater than 1:512, indicating the presence of current infection or reinfection. Age older than 60 years (vs. < or = 60 years) was a risk factor for C. pneumoniae seropositivity in patients with community-acquired pneumonia (p < 0.001). Males had a significantly higher seroprevalence of C. pneumoniae infection (p = 0.1010). Patients older than 60 years were more likely to have C. pneumoniae infection (p = 0.1107). In this series, C. pneumoniae infection accounted for 10.9% (25/229) of community-acquired pneumonia. The most common clinical manifestations included fever (92%), productive cough (52%), white blood cell more than 10,000/mm3 (56%), and bilateral pulmonary infiltrate (60%).

Community-acquired methicillin-resistant Staphylococcus aureus endocarditis with septic embolism of popliteal artery: a case report

A 20-year-old man presented with a 14-day course of fever. Physical examination showed petechiae of the conjunctivae, Janeway lesions on both hands, a grade III/VI systolic murmur over the apex, pulseless dorsal pedal artery and posterior tibial artery of the right leg, and a pale right foot. Femoral arteriogram of the right leg revealed total occlusion of the popliteal artery with collateral circulation of the posterior tibial artery. Transthoracic echocardiogram showed trace mitral regurgitation. Embolectomy of the right popliteal artery was done, and penicillin and gentamicin treatment was administered. However, postoperative fever developed intermittently. Transesophageal echocardiogram disclosed vegetation over the anterior leaflet of the mitral valve. Methicillin-resistant Staphylococcus aureus (MRSA) was isolated from all three cultures of blood drawn at admission and from the septic embolus during operation. He had neither evidence of underlying heart disease, nor history of intravenous drug abuse or hospitalization. Exploratory cardiotomy with removal of vegetation on the mitral valve was performed followed by a 4-week treatment with intravenous vancomycin. After discharge, he was well at 2-year follow-up.

Detection of circulating tumor cells in venous blood of nasopharyngeal carcinoma patients by nested reverse transcriptase-polymerase chain reaction

Nasopharyngeal carcinoma (NPC) is a radiosensitive tumor. Because of recent advances in radiation oncology, distant metastasis has become the predominant failure site after adequate radiotherapy. The purpose of this study is to establish a nested reverse transcriptase-polymerase chain reaction (RT-PCR) system and to evaluate the potential of cytokeratin 19 (CK-19) mRNA as a target for detecting micrometastasis in the blood of NPC patients. Venous blood samples from 40 patients with biopsy-proven NPC (25 previously untreated and 15 after radiotherapy) and 20 healthy volunteers were tested. We divided the 40 patients into 4 groups: cured, early stage, advanced stage, and metastasized, according to results of clinical staging work-up. Under our nested RT-PCR experimental conditions, 2 of 8 early stage patients (25.0%), 6 of 15 advanced stage patients (40%), and 6 of 8 patients with distant metastasis (75%) had CK-19 positive cells in peripheral blood (P = 0.11). No CK-19 positive cells were detected in 9 "cured" patients and 20 healthy volunteers. Our data indicated that the positive detection rate for CK-19 mRNA in peripheral blood increased as the clinical stage of disease increased, but the difference did not reach statistical significance. Longer follow-up is needed to assess the significance of CK-19 mRNA in blood, as well as its relation to subsequent metastasis and prognosis of NPC.

Relapsing pancreatitis in a child duplication in an aberrant pancreatic lobe

An aberrant pancreatic lobe associated with an enteric duplication cyst is a rare cause of relapsing pancreatitis in childhood. We present an 8-year-old boy with relapsing pancreatitis caused by this rare congenital foregut anomaly. The computed tomography (CT) findings revealed an unusually long segment of aberrant pancreatic lobe arising from the pancreatic neck, projecting anteriorly at a distance to a cystic duodenal duplication and appearing as an inflammatory mass. There has been no previous report of this unusual appearance on CT. Appreciation of the relevant anatomy provided by CT led to the successful management of this surgically-treatable cause of relapsing pancreatitis.