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Biomedical subjects

M Y Chen

Publications and source records attributed to M Y Chen.

At least 91 records · Page 5Linked to original sources
PubMed1999

The effectiveness of health promotion counseling to family caregivers.

This study examined the effectiveness of health promotion counseling of the family caregivers from Taipei Metropolitan Area. An established Chinese version of the health-promoting scale was developed by the author of this study (which was modified and authorized by Walker, Sechrist, & Pender, 1987). A two-group quasi-experimental research design was employed. From October 1996 to July 1997, 84 family caregivers were selected and assigned to one of the two groups. Members of the treatment group received health promotion counseling from four trained professional home care nurses during home visiting. The members of the control group were given no counseling but instead received traditional care. Pre-assessment was carried out after subjects were selected and post evaluation was done 6 months later. The findings showed that the counseling enabled members of the treatment group to adopt healthier lifestyles. The research outcome supports the value of home-care nurse counseling of family caregivers.

Adult↗
PubMed1999

Expression of bone morphogenetic protein 7 in murine epididymis is developmentally regulated.

Bone morphogenetic proteins (BMPs) have been shown to play a role in the functional maintenance of the adult epididymis. To begin to investigate the role of BMP signal transduction during postnatal epididymal development, we examined the expression profile of Bmp7 in murine epididymis by in situ hybridization. Our data show that during early postnatal development (younger than 3 wk of age), Bmp7 transcripts are detected uniformly in epithelial cells throughout the epididymis. As the mice aged (from 3 to 4 wk), Bmp7 expression was gradually restricted to the initial segment, with increased levels. Bmp7 expression in the rest of the caput and corpus regions became undetectable after 4 wk of age. However, after 4 wk of age, an ascending gradient of Bmp7 expression was observed in the epididymal epithelial cells in the transition from the cauda epididymal tubule to the vas deferens. Such a unique expression profile of Bmp7 strongly suggests that epididymis-produced BMP7 may play a role in the development and functional maintenance of the epididymis, and that Bmp7 expression in the epididymis is developmentally regulated.

Animals↗
PubMed1999

Epstein-Barr virus-associated intravascular lymphomatosis within Kaposi's sarcoma in an AIDS patient.

Intravascular lymphomatosis (IL) is an unusual neoplasm characterized by multifocal proliferation of lymphoma cells exclusively within the blood vessels. We report here a patient with acquired immunodeficiency syndrome (AIDS) and disseminated Kaposi's sarcoma. A 233-bp amplification product of HHV-8 was detected in the DNA extracted from specimens of Kaposi's sarcoma at different sites by polymerase chain reaction (PCR). At autopsy, the vessels within the Kaposi's sarcoma were dilated and filled with atypical large mononuclear cells. No such feature was seen in the vessels of non-Kaposi's sarcomatous regions. Immunohistochemically, the spindle cells of Kaposi's sarcoma were positive for CD31 (endothelial cell marker). The intravascular tumor cells were positive for CD45 (leukocyte common antigen) but negative for others, including chloroacetate esterase, CD45-RO (UCHL-1, Pan-T), CD3, CD43, CD20 (L26, Pan-B), CD30 (Ki-1), immunoglobulin heavy chains and light chains, CD56 (natural killer cell antigen), and CD31. Monoclonal rearrangement of immunoglobulin heavy chain gene was detected in the DNA extracts from fresh tissue of Kaposi's sarcoma by PCR, which indicated that the lymphoma cells within the Kaposi's sarcoma were of monoclonal B cell origin. In situ hybridization revealed that EBER-1 transcripts were present in the lymphoma cells of IL but not in the spindle cells of Kaposi's sarcoma. To the authors' best knowledge, this is the first instance of IL in an AIDS patient with direct evidence of EBV association.

Biomarkers, Tumor↗
PubMed1999

Sonohysterography: the next step in the evaluation of the abnormal endometrium.

Sonohysterography is a simple ultrasound (US) procedure that may be used to evaluate the endometrium. The technique involves placement of a 5-F catheter into the endometrial canal with subsequent instillation of sterile saline solution under US guidance. Fifty patients successfully underwent sonohysterography because of apparent abnormal endometrial thickening at transvaginal US, a nonspecific finding. Patients tolerated this procedure well, and no complications were encountered. In the 39 patients who proved to have endometrial pathologic conditions, sonohysterography demonstrated focal processes (polyps, carcinoma, hamartoma) in 15, diffuse processes (hyperplasia, secretory endometrium) in 21, and both focal and diffuse pathologic conditions in three. If a focal process can be delineated, a visually directed biopsy may be necessary. However, if the process is diffuse, a blind aspiration biopsy may be performed on an outpatient basis. In the majority of patients, the diffuse or focal nature of the disease could not be predicted on the basis of initial transvaginal US. Because sonohysterography allows distinction between diffuse and focal abnormalities, it provides physicians with a cost-effective way to plan the next step in case management.

Adult↗
PubMed1999

Focal delivery during direct infusion to brain: role of flow rate, catheter diameter, and tissue mechanics.

Direct interstitial infusion is a technique capable of delivering agents over both small and large dimensions of brain tissue. However, at a sufficiently high volumetric inflow rate, backflow along the catheter shaft may occur and compromise delivery. A scaling relationship for the finite backflow distance along this catheter in pure gray matter (x(m)) has been determined from a mathematical model based on Stokes flow, Darcy flow in porous media, and elastic deformation of the brain tissue: x(m) = constant Q(o)(3)R(4)r(c)(4)G(-3)mu(-1) 1/5 [corrected] = volumetric inflow rate, R = tissue hydraulic resistance, r(c) = catheter radius, G = shear modulus, and mu = viscosity). This implies that backflow is minimized by the use of small diameter catheters and that a fixed (minimal) backflow distance may be maintained by offsetting an increase in flow rate with a similar decrease in catheter radius. Generally, backflow is avoided in rat gray matter with a 32-gauge catheter operating below 0.5 microliter/min. An extension of the scaling relationship to include brain size in the resistance term leads to the finding that absolute backflow distance obtained with a given catheter and inflow rate is weakly affected by the depth of catheter tip placement and, thus, brain size. Finally, an extension of the model to describe catheter passage through a white matter layer before terminating in the gray has been shown to account for observed percentages of albumin in the corpus callosum after a 4-microliter infusion of the compound to rat striatum over a range of volumetric inflow rates.

Animals↗
PubMed1999

Radiographic anatomy: multimedia interactive instructional software on CD-ROM.

OBJECTIVE: We wanted to create a filmless radiographic anatomy curriculum, a didactic software with a digital image database on CD-ROM for first-year medical students. CONCLUSION: We created a CD-ROM that includes an introduction, radiographic anatomy tutorial, and interactive questions. Additional features include Boolean text searching, links to related images, and Internet accessibility. The software can be updated.

Anatomy↗
PubMed1999

Trends in the use of unenhanced helical CT for acute urinary colic.

OBJECTIVE: Unenhanced helical CT for urolithiasis detection is a limited CT examination that was designed specifically for the detection of urolithiasis. The purpose of this study was to repeat a prior study to assess whether clinicians had broadened the indications and changed the yield and findings of unenhanced helical CT. MATERIALS AND METHODS: One hundred consecutive patients with suspected renal colic or flank pain referred for unenhanced helical CT were selected for this study. We reviewed the original radiographic reports for each patient and recorded the presence of ureteral calculi. Other urinary abnormalities and extraurinary lesions were also recorded and compared with the results of the previous study. RESULTS: In this study, 56% of the patients who underwent unenhanced helical CT had symptoms of urinary colic, and 44% of patients had unspecified flank pain, compared with 100% of patients with symptoms of urinary colic 1 year earlier. The sensitivity and specificity of unenhanced helical CT in detecting ureteral calculi were 96% and 99%, respectively. Ureteral calculi were identified in only 28% of the patients versus 49% of patients (p < .01) 1 year earlier. Extraurinary lesions were identified in 45% of the patients versus 16% (p < .01) 1 year before. CONCLUSION: As clinicians developed familiarity with this technique, the indications for performance of unenhanced helical CT were expanded with a consequent reduction in the rate of detection of stone disease and identification of an increased number of extraurinary lesions, which suggests a demand for emergency abdominal CT studies.

Acute Disease↗
PubMed1999

Variables affecting convection-enhanced delivery to the striatum: a systematic examination of rate of infusion, cannula size, infusate concentration, and tissue-cannula sealing time.

OBJECT: Although recent studies have shown that convection can be used to distribute macromolecules within the central nervous system (CNS) in a homogeneous, targeted fashion over clinically significant volumes and that the volume of infusion and target location (gray as opposed to white matter) influence distribution, little is known about other factors that may influence optimum use of convection-enhanced distribution. To understand the variables that affect convective delivery more fully, we examined the rate of infusion, delivery cannula size, concentration of infusate, and preinfusion sealing time. METHODS: The authors used convection to deliver 4 microl of 14C-albumin to the striatum of 40 rats. The effect of the rate of infusion (0.1, 0.5, 1, and 5 microl/minute), cannula size (32, 28, and 22 gauge), concentration of infusate (100%, 50%, and 25%), and preinfusion sealing time (0 and 70 minutes) on convective delivery was examined using quantitative autoradiography, National Institutes of Health image analysis software, scintillation analysis, and histological analysis. Higher rates of infusion (1 and 5 microl/minute) caused significantly (p < 0.05) more leakback of infusate (22.7+/-11.7% and 30.3+/-7.8% [mean+/-standard deviation], respectively) compared with lower rates (0.1 microl/minute [4+/-3.6%] and 0.5 microl/minute [5.2+/-3.6%]). Recovery of infusate was significantly (p < 0.05) higher at the infusion rate of 0.1 microl/minute (95.1+/-2.8%) compared with higher rates (85.2+/-4%). The use of large cannulae (28 and 22 gauge) produced significantly (p < 0.05) more leakback (35.7+/-8.1% and 21.1+/-7.5%, respectively) than the smaller cannula (32 gauge [5.2+/-3.6%]). Varying the concentration of the infusate and the preinfusion sealing time did not alter the volume of distribution, regional distribution, or infusate recovery. CONCLUSIONS: Rate of infusion and cannula size can significantly affect convective distribution of molecules, whereas preinfusion sealing time and variations in infusate concentration have no effect in this small animal model. Understanding the parameters that influence convective delivery within the CNS can be used to enhance delivery of potentially therapeutic agents in an experimental setting and to indicate the variables that will need to be considered for optimum use of this approach for drug delivery in the clinical setting.

Animals↗
PubMed1999

Opportunistic hepatic infections in AIDS patients with fever of unknown origin.

The clinical features and histopathologic manifestations of hepatic opportunistic infections in patients with acquired immunodeficiency syndrome (AIDS) in Taiwan remain unexplored. We report 28 AIDS patients (25 men, 3 women; mean age, 34 years) with fever of unknown origin who underwent 31 liver biopsies from December 1995 to May 1997. In most cases, the biochemical tests showed moderate to markedly elevated alkaline phosphatase concentrations, but normal or mildly elevated aminotransferase concentrations. The most common histopathologic finding was macrosteatosis, which was noted in 15 of the 28 patients. Another important histopathologic finding indicating the etiology of hepatic opportunistic infection was granuloma, which was found in 11 patients. Histochemical stain and culture of liver specimens yielded Mycobacterium avium complex (MAC) in eight patients, Mycobacterium tuberculosis in two patients, Histoplasma capsulatum in one patient, and cytomegalovirus in one patient with concomitant MAC infection. Therefore, a definitive diagnosis in AIDS patients with fever of unknown origin was made in 11 of the 28 cases with the assistance of liver biopsy. During follow-up, late extrahepatic involvement by the same infectious agents was found in six patients. Thus, hepatic manifestations could be a harbinger of disseminated opportunistic infections in AIDS patients.

AIDS-Related Opportunistic Infections↗
PubMed1999

Ultrasound-guided percutaneous transthoracic needle aspiration biopsy for diagnosis of pulmonary lesions in advanced HIV infection.

Pulmonary diseases remain the most common complication associated with high morbidity and mortality in patients with human immunodeficiency virus (HIV) infection. Invasive diagnostic procedures are often needed to establish a specific diagnosis of pulmonary disease. We report our experience with ultrasound (US)-guided percutaneous transthoracic needle aspiration (PTNA) biopsy in 20 consecutive patients with advanced HIV infection who presented with a variety of pulmonary lesions with or without pleural effusion. A specific diagnosis was established in 16 patients (80%), with infection being the most common etiology. Sputum culture yielded the same causative pathogen in three patients (15%) and all had more than one bacterial or fungal isolates. Mild pneumothorax, the only complication, was observed in two patients (10%) following the procedure. Neither patient required chest tube drainage. Our findings suggest that US-guided PTNA can be a useful and safe alternative to fluoroscopy-guided PTNA in selected HIV-infected patients with focal pulmonary lesions and pleural effusion.

AIDS-Related Opportunistic Infections↗
PubMed1999

The role of tissue studies in facilitating early initiation of antimycobacterial treatment in AIDS patients with disseminated mycobacterial disease.

SETTING: The question of whether aggressive investigations are useful in diagnosis and initiation of treatment in AIDS patients with disseminated mycobacterial disease (DMD) is still under debate. OBJECTIVE: To define the role of tissue studies in facilitating early initiation of antimycobacterial treatment and in establishing diagnosis in AIDS patients with DMD. DESIGN: From July 1994 through June 1997, 167 AIDS cases with fever were evaluated by stepwise investigation using a standardized protocol. Data of DMD cases were analyzed to define the role of tissue studies. RESULTS: A total of 40 cases of culture-proven DMD were identified. Antimycobacterial treatment was initiated due to positive acid-fast bacilli smears of sputum in only five cases. In the remaining cases, positive pathologic findings from tissue biopsies (lymph node, bone marrow or liver) facilitated early initiation of treatment in 60% (21/35). In 50% of all cases (20/40), the diagnosis could not have been established if cultures of tissue biopsies had not been performed. Both the pathologic examinations and mycobacterial cultures from liver biopsies had positivity rates of more than 50% (53.8% and 69.2%, respectively). CONCLUSIONS: Tissue studies were useful in facilitating early initiation of treatment and establishing diagnosis at least in half of the AIDS cases with DMD. Liver biopsy is worthwhile if the cause of fever is not discovered using less invasive investigations.

AIDS-Related Opportunistic Infections↗
PubMed1999

Abnormal calcification on plain radiographs of the abdomen.

The purpose of this pictorial review is to facilitate recognition and understanding of calcifications seen on conventional radiographs of the abdomen. Calcifications can be categorized by organ system and location in the abdomen. Both common and rare calcifications in the urinary tract, liver, gallbladder, spleen, pancreas, adrenal glands, digestive tract, genital tract, peritoneal cavity, and retroperitoneum are illustrated. Abnormal calcifications in the urinary tract are subcategorized by kidneys, ureters, bladder, and urethra. The density, shape, size, margins, pattern, position, and mobility of calcifications are emphasized for differential diagnoses.

Adrenal Glands↗
PubMed1999

[The study of family structure, illness symptom, and stress adaptation of psychotic patients].

The major purposes of this paper are to explore the phenomena of family structure, illness symptoms, family coping and adaptation for patients with schizophrenia or manic-depression psychosis. This paper tries to provide a good reference instrument for application by nurses in home care, in order to understand and evaluate family needs. Subjects are schizophrenic or manic-depression outpatients from 3 hospitals located in northern Taiwan. Data were collected through home interview with primary caregivers and observations. There were fifty subjects from each of the 3 hospitals, and 151 subjects in total. Descriptive statistics, t-test, one way ANOVA, Pearson correlation and multiple stepwise correlation were used to analyze data. Research indicates that most patients are aged between 31 to 40, with over 10 years elapsed since onset, and are not married. Most primary caregivers are parents over 60 years old. Most family development was at the stage with young adult offspring. The manic-depressive patients have more working opportunities than schizophrenic patients. For schizophrenic patients, paranoia was the most serious in active symptoms; lack of interpersonal interaction was the most serious in negative symptoms; the other major problem was sleep disturbance in emotion-behavior assessment. Patient's disposition was the most concerning issue for families and the worst coping efficiency occurred with lazy behavior and sleep disturbance. For manic-depressive patients, aggressive behavior was the most serious active symptom, lack of energy was the most serious in negative symptom, and sleep disturbance was the most concerning problem in emotion-behavior assessment. The patient's symptom was the most concerning issue for families and the worst coping efficiency was found in drug side effect. The result also indicates that active and negative symptoms are both related to coping efficiency.

Adaptation, Psychological↗
PubMed1999

Pattern of defervescence in response to anti-tuberculosis therapy in patients with extrapulmonary tuberculosis and advanced human immunodeficiency virus infection.

The pattern of fever response to empiric anti-tuberculosis therapy in patients with tuberculosis (TB) and human immunodeficiency virus (HIV) infection, and the relationship between fever response patterns and anti-TB drug susceptibility profiles of Mycobacterium tuberculosis isolates are rarely described. In this study, we evaluated the fever responses to a four-drug anti-TB regimen in 26 HIV-infected patients with culture-proven extrapulmonary TB, and compared the results with those in 12 patients with disseminated Mycobacterium avium complex (DMAC) infection treated with a clarithromycin-containing regimen. The CD4 lymphocyte counts did not differ significantly between TB and DMAC patients (26 x 10(6)/L in TB patients vs 5 x 10(6)/L in DMAC patients). Drug susceptibility data were available for 22 patients with TB. Most TB patients had rapid defervescence after initiation of anti-TB therapy. Fever resolved within 1 week in 85% (22/26) of patients, including three of six (50%) with multidrug-resistant (MDR) TB. The median duration of fever in patients with drug-susceptible TB was similar to that in patients with drug-resistant TB (3 vs 4 days, p = 0.33). However, patients with MDR-TB were more likely than those with non-MDR TB to have fevers lasting longer than 1 week after initiating anti-TB therapy (3/6 vs 1/16, p = 0.046). Only 17% (2/12) of the patients with DMAC infection became afebrile within 1 week of beginning anti-MAC therapy (p < 0.001 vs those with TB). Our observations suggest that in HIV-infected patients with advanced immunosuppression, anti-TB regimens achieve significantly faster defervescence in TB patients than do anti-MAC regimens in DMAC patients. Rapid defervescence in patients with TB does not necessarily indicate that TB isolates are not MDR strains.

AIDS-Related Opportunistic Infections↗
PubMed1999

[Analysis of 50 cases of sexual dysfunction].

Fifty cases of male sexual dysfunction were analyzed in order to investigate the incidence and causes of the erectile dysfunction in the different injuries. The results showed that the incidence of erectile dysfunction of the patients with brevic fracture and urethra injury is 62.50%, main caused by the damage of pudendal nervous and arterial system. The incidence in the patients with the spinal fracture and light spinal cord injury is 50%, caused by the damage of nervous system. The erection in the 17 cases of the patients with only one testis injury is normal. Two cases with bilateral testis injury have suffered from erectile dysfunction.

Adolescent↗
PubMed1998

Clinical features and outcome in disseminated mycobacterial diseases in AIDS patients in Taiwan.

OBJECTIVE: To describe and compare the clinical features and outcome of disseminated tuberculosis (TB) and Mycobacterium avium complex (MAC) disease in AIDS patients. DESIGN: Prospective cohort study. SETTING: A 1800-bed university teaching hospital, the largest centre for HIV/AIDS patients in Taiwan. METHODS: From July 1994 through June 1997, a standardized protocol was used to record the demographic and clinical features in all hospitalized HIV-infected patients, and to perform routine studies and invasive procedures for diagnosis of disseminated mycobacterial diseases. To compare the survival, control patients were selected from the HIV-infected patients hospitalized in the same hospital during the same study period, and had similar age, sex, CD4+ cell counts and antiretroviral therapy regimens. RESULTS: A total of 22 cases of disseminated TB and 15 cases of disseminated MAC were identified. Disseminated TB and MAC occurred in patients with similarly low CD4+ cell counts (median, 23 versus 5 x 10(6)/l; P = 0.08). The clinical features favouring disseminated TB included night sweats, peripheral lymphadenopathy, acid-fast bacilli in sputum smears, chest radiographic findings of hilar enlargement, and lack of prior AIDS-defining illnesses. Hepatosplenomegaly, elevated serum alkaline phosphatase (more than twice the upper limit of normal), elevated serum gamma-glutamyl transpeptidase (more than three times the upper limit of normal), and leukopenia favoured disseminated MAC. The patients with disseminated TB survived much longer than patients with disseminated MAC (mean survival, 96 versus 22 weeks, P = 0.008) but had a similar outcome to control patients (P = 0.60). CONCLUSION: Disseminated TB and MAC are distinguishable by clinical features in AIDS patients with similar immunocompromised states. Those features may facilitate diagnosis and selection of specific therapeutic regimens. Disseminated TB was not associated with a shortened survival period in AIDS patients when they completed anti-TB treatment. In contrast, disseminated DMAC was associated with shortened survival despite treatment with potent regimens. These results may emphasize the importance of prophylaxis for MAC in this population.

AIDS-Related Opportunistic Infections↗