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Biomedical subjects

B Kim

Publications and source records attributed to B Kim.

At least 217 records · Page 12Linked to original sources
PubMed1975

Small cell epidermoid carcinoma of the esophagus. An oat-cell-like carcinoma.

A case of small cell anaplastic epidermoid carcinoma of the esophagus is reported. The morphology of this rare esophageal neoplasm simulates that of oat cell carcinoma. Four similar cases have been previously reported. The finding of epidermoid differentiation in two of these tumors, including the present one, raises considerable doubt that any are truly oat cell carcinomas of the esophagus. Although it is theoretically possible that an oat cell carcinoma may arise in the esophagus, there is as yet no conclusive evidence for the existence of such an entity.

Aged↗
PubMedDate not supplied

Pelvic fistulas: appearances on MR images.

BACKGROUND: This multi-institutional study examines appearances of pelvic fistulas on magnetic resonance (MR) images. METHODS: MR images of 46 patients with documented fistulas from five teaching hospitals were retrospectively reviewed. All patients underwent T1-weighted (T1WI), T2-weighted (T2WI), and intravenous gadolinium chelate-enhanced T1-weighted (Gd-T1WI) images. Imaging sequences were separately and then collectively reviewed. The following determinations were made: fistula detection, fistula morphology and signal intensity, and the presence of associated abnormalities. Fistulas were classified into two categories: (1) fistulas that communicate with the bladder and (2) fistulas that do not communicate with the bladder. Fistulas within these two groups were subclassified further. The presence of fistulas was documented by surgery (five patients), endoscopy (six patients), fistulogram (20 patients), or physical exam (15 patients). RESULTS: Among the 46 patients, 53 fistulas were documented by means other than MR. Overall T1WI, T2W1 and Gd-T1WI images demonstrated 23, 31, and 39 of 53 fistulas, respectively. Gd-T1W1 detected significantly more fistulas than T1W1 (p < 0.05). Bladder fistulas were better shown on Gd-T1WI (8/15 fistulas) than on T1WI and T2WI (2/15 and 3/15) (p < 0. 05). Nonbladder fistulas were demonstrated by T1WI, T2WI, and Gd-T1WI images in 21, 28, and 31 of 38 fistulas, respectively. Among all fistulas, perianal fistulas (a subcategory of nonbladder fistula) had the highest detection by T1WI, T2WI, and Gd-T1WI in 19, 20 and 22 of 23 fistulas, respectively. On T1WI, 19 of 23 detected fistulas were low in signal intensity. On T2WI, 28 of 39 detected fistulas were high in signal intensity. On Gd-T1WI images, 29 of 40 fistulas were low in signal intensity, with enhanced tract wall. CONCLUSION: Bladder fistulas were best shown on Gd-T1WI, which was significantly greater than on T1WI or T2WI. Nonbladder fistulas were comparably shown by all techniques, with all performing modestly well. Perianal fistulas were shown equally well by all MR sequences and were the fistulas demonstrated with the highest sensitivity on MR images.

Adolescent↗
PubMedDate not supplied

Expression of Interferon-gamma and tumour necrosis factor-alpha in pigs experimentally infected with Porcine Reproductive and Respiratory Syndrome Virus (PRRSV).

The expression of mRNA encoding interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) was studied, by reverse transcription-polymerase chain reaction and by in-situ hybridization with a non-radioactive digoxigenin-labelled probe, in formalin-fixed, paraffin wax-embedded lung tissue from pigs experimentally infected with a Korean isolate (North American genotype) of PRRSV. Both IFN-gamma and TNF-alpha mRNA were detected in the lung as early as 1 day post-inoculation (dpi) and up to 10 dpi. Hybridization signals for IFN-gamma and TNF-alpha were usually associated with inflammation, in particular with macrophages within alveolar septa. Expression of these cytokines was minimal in non-lesional lung of PRRSV-infected pigs and in normal lung from control pigs. The results suggest that IFN-gamma and TNF-alpha play a role in pulmonary defence against PRRSV.

Animals↗
PubMedDate not supplied

Normal limits for left ventricular ejection fraction and volumes estimated with gated myocardial perfusion imaging in patients with normal exercise test results: influence of tracer, gender, and acquisition camera.

BACKGROUND: Myocardial imaging with tracers such as technetium-99m sestamibi or thallium-201 is extensively used as a means of measuring myocardial perfusion. With gated acquisition, these tracers can also be used as a means of measuring left ventricular ejection fraction (EF) and end diastolic and end systolic volumes (EDV and ESV, respectively). The objective of this study was to determine the normal range of EF, EDV, and ESV and to evaluate differences caused by either the tracer used, the gender of the patient, or the acquisition camera used. METHODS AND RESULTS: A total of 1513 consecutive patients (mean age, 60+/-12 years [SD]) who had normal results on Bruce exercise tests had either Tc-99m sestamibi (n = 884) or Tl-201 (n = 629) injected at peak stress. Although all patients were referred for the evaluation of chest pain or dyspnea and many had cardiac risk factors, all had normal exercise capacity corrected for age, no electrocardiographic signs of ischemia, normal results on perfusion scans, and normal wall motion determined by means of quantitated gated single photon emission computed tomography (QGS). Scans were acquired on 1 of 3 different cameras. The mean EF for all patients who had gated Tc-99m sestamibi scans was 63% +/- 9%, not different from patients who had gated Tl-201 scans (63% +/- 9%). However, when the gender of the patient was considered, the mean EF for women was 66% +/- 8% with Tc-99m sestamibi (n = 519), higher than the mean EF for men (58% +/- 8%, n = 365, P<.0001). Similarly, the mean EF for women studied with Tl-201 (67% +/- 8%, n = 326) was higher than that of men (59% +/- 7%, n = 303,P<.0001). Patients with diabetes mellitus (n = 153) had a slightly reduced EF (62% +/- 10%, P<.001). In a subset of 240 patients, 140 patients studied with Tc-99m sestamibi and 100 studied with Tl-201, the EDV and ESV for women (n = 124) was estimated by means of QGS to be lower (57 +/- 17 mL and 19 +/- 11 mL, respectively) than those for men (74 +/- 22 mL-and 29 +/- 13 mL, respectively; n = 116; P<.001 for each comparison). No clinically significant differences in EF or volumes were noted based on tracers used or acquisition camera. For patients with normal results on exercise treadmill tests and perfusion imaging, the lower limit of normal for EF with gated perfusion imaging with QGS was 50% for women and 43% for men. For EDV and ESV, the upper limit of normal was 91 mL and 40 mL, respectively, for women and 119 mL and 55 mL, respectively, for men. CONCLUSIONS: No significant differences related to either tracer or acquisition camera used were noted for EF, suggesting equivalency for clinical trials for patients with normal results on exercise tests. However, EF, EDV, and ESV determined by means of gated perfusion imaging need to be corrected for gender.

Adult↗
PubMedDate not supplied

Continuation of gas from the right perirenal space into the bare area of the liver.

PURPOSE: It is difficult to explain some CT findings pertaining the anatomic relationship between the bare area of the liver and the right retroperitoneal space on the basis of the traditional three compartment concept of retroperitoneal anatomy. The purpose of this article is to ascertain and illustrate possible communication between the bare area of the liver and the right perirenal space in patients with gas-forming retroperitoneal infection. METHOD: We reviewed CT findings in 24 cases with retroperitoneal gas-forming condition with particular emphasis on the extent of the infection and resultant distribution of gas. RESULTS: CT images showed gas within the right perirenal space extended upward directly into the bare area of the liver in six cases. CONCLUSION: The right perirenal space is considered open toward the bare area of the liver. Therefore, gas within the perirenal space may communicate directly with the bare area of the liver.

Emphysema↗
PubMedDate not supplied

A case of alveolar soft part sarcoma with vaginal metastasis: successful control of vaginal bleeding with external beam irradiation.

Alveolar soft part sarcoma (ASPS) of the vagina is an exceptionally rare neoplasm. Furthermore, vaginal metastasis of ASPS has not been reported. A 28-year-old woman with a history of a right thigh mass diagnosed as ASPS excised 8 years ago presented to the emergency room with massive vaginal bleeding and anemia. Biopsy of a vaginal mass revealed that the tumor was a vaginal metastasis of ASPS. For control of intractable bleeding and preventing further transfusions, palliative radiation therapy was planned. She received a total of 39 Gy (daily 3 Gy, using 15-MV photons), and after 6-Gy irradiation, there was no more vaginal bleeding and no more transfusion needed. This is the first case of vaginal metastasis of ASPS reported in the literature that was manifested by intractable vaginal bleeding, which was controlled successfully with radiation therapy.

Adult↗
PubMedDate not supplied

Sex cord-stromal and steroid cell tumors of the ovary.

Gonadal cell types that derive from the coelomic epithelium (sex cords) or mesenchymal cells of the embryonic gonads include granulosa cells, theca cells, fibroblasts, Leydig cells, and Sertoli cells. Ovarian tumors of these cell types are called sex cord-stromal tumors. This group of tumors represents approximately 8% of ovarian neoplasms and affects all age groups. The more common types are granulosa cell tumors (GCTs), fibrothecomas, and Sertoli-Leydig cell tumors. Sex cord-stromal tumors are of interest partly because of their hormonal effects, which are rare for other ovarian neoplasms. These effects include estrogenic effects (pseudoprecocious puberty, endometrial bleeding, endometrial hyperplasia and carcinoma) and virilization. The variety of gross appearances of these tumors, ranging from large multicystic masses to small solid masses, would appear to preclude a specific radiologic diagnosis. However, in many patients, both clinical and radiologic clues can suggest the diagnosis, including predominantly fibrous content at ultrasound or magnetic resonance imaging (fibrothecoma), large hemorrhagic multicystic mass in a child with pseudoprecocious puberty (juvenile GCT), and associated syndromes such as Peutz-Jeghers syndrome (sex cord tumor with annular tubules) or Ollier disease and Maffucci syndrome (juvenile GCT).

Diagnostic Imaging↗
PubMedDate not supplied

MR imaging of acute penile fracture.

Penile fracture is a rare but serious urologic condition that typically requires surgical repair. Because of its multiplanar capability and excellent tissue contrast, magnetic resonance (MR) imaging can be a useful diagnostic tool in the evaluation of patients with acute penile fracture. MR imaging can accurately depict the presence, location, and extent of tunical tear, which manifests as discontinuity of the tunica albuginea. Moreover, because the tunica albuginea is well demonstrated as a low-signal-intensity structure on both T1- and T2-weighted images, MR imaging is optimal for the evaluation of the integrity of this anatomic structure even in patients with severe pain and swelling of the penis. This capability makes MR imaging particularly helpful in determining the need for surgical intervention, which is largely based on the integrity of the tunica albuginea. Associated injuries to adjacent structures (eg, corpus spongiosum, urethra) can also be demonstrated. In patients with no penile fracture, MR imaging can demonstrate an intact tunica albuginea and the presence of intracavernosal or extratunical hematoma. It remains uncertain whether the routine use of contrast material-enhanced MR imaging is justified, and further study is needed to determine the role of this modality.

Acute Disease↗
PubMedDate not supplied

MR imaging of the male and female urethra.

Conventional radiographic contrast material-enhanced studies (eg, retrograde urethrography [RUG], voiding cystourethrography [VCUG], double-balloon catheter urethrography) and ultrasonography are useful in evaluating the anatomy of the urethra but are limited in demonstrating anatomic derangement of adjacent structures. Since the anatomic details of both the urethra and periurethral tissues can be evaluated noninvasively with magnetic resonance (MR) imaging, this modality can be used as an adjunctive tool for evaluation of urethral abnormalities. In patients with congenital anomalies, MR imaging is reserved for cases of intersex anomalies or complex genitourinary anomalies, in which evaluation of internal organs is essential. MR imaging may demonstrate diverticula that are not seen on radiographic contrast-enhanced studies, including VCUG, RUG, or double-balloon catheter study. In cases of inflammation, MR imaging can demonstrate not only inflammatory infiltration around the urethra but also the presence of a periurethral abscess or sinus tract. In cases of trauma, MR imaging is helpful in assessing the presence and extent of anterior or posterior urethral injury and predicting the occurrence of complications. At MR imaging, a fistula can be seen as a direct communicating channel with an adjacent organ. In patients with urethral tumors, the major role of MR imaging is in local staging.

Female↗
PubMedDate not supplied

Adaptation-dependent differences in electroretinographic latency patterns in uniform and variegated horseshoe crabs.

The carapaces of horseshoe crabs (Limulus polyphemus) differ. Some individuals have uniform carapaces and clear eyes while others have variegated carapaces and dark eyes. These differences have been reported to be correlated with latency differences in the electroretinogram (ERG) of the lateral eye. Such a result might have had a neural basis in the mechanisms underlying visual transduction but it could also have reflected a visual screening pigment difference. A direct experiment was therefore designed to choose between these two hypotheses by varying the relative state of adaptation. The results were as follows. In uniform animals, dark adaptation had the kind of effect seen in single photoreceptor cells - latencies were longer in dark-adapted eyes and latencies were also longer for dim flashes. However, variegated animals showed a significant adaptation interaction: in light adaptation, dimmer flashes produced the usual effect, namely a longer ERG latency, while in dark adaptation, latencies were close to equilatent, being within experimental error of each other for both flash energies. These data make it unlikely that the photoreceptor transduction mechanism is the locus of the visual differences between the two types of animals. Instead, they are consistent with an interaction of screening pigment effects with photoreceptor transduction effects.

Adaptation, Physiological↗
PubMedDate not supplied

Unenhanced spiral CT in acute ureteral colic: a replacement for excretory urography?

OBJECTIVE: To compare the usefulness of unenhanced spiral CT (UCT) with that of excretory urography (EU) in patients with acute flank pain. MATERIALS AND METHODS: Thirty patients presenting with acute flank pain underwent both UCT and EU. Both techniques were used to determine the presence, size, and location of urinary stone, and the presence or absence of secondary signs was also evaluated. The existence of ureteral stone was confirmed by its removal or spontaneous passage during follow-up. The absence of a stone was determined on the basis of the clinical and radiological evidence. RESULTS: Twenty-one of the 30 patients had one or more ureteral stones and nine had no stone. CT depicted 22 of 23 calculi in the 21 patients with a stone, and no calculus in all nine without a stone. The sensitivity and specificity of UCT were 96% and 100%, respectively. EU disclosed 14 calculi in the 21 patients with a stone and no calculus in eight of the nine without a stone. UCT and EU demonstrated secondary signs of ureterolithiasis in 15 and 17 patients, respectively. CONCLUSION: For the evaluation of patients with acute flank pain, UCT is an excellent modality with high sensitivity and specificity. In near future it may replace EU.

Adult↗