Effect of nanogroove geometry on adipogenic differentiation

We present the effect of nanotopographically defined surfaces on adipocyte differentiation using various nanogroove patterns. Parallel nanogroove arrays with equal inter-groove distance (400, 550, 800 nm width) and varying distances (550 nm width with three different spacings of 550, 1100, and 2750 nm) were fabricated by UV-assisted capillary force lithography (CFL) on 18 mm diameter glass coverslips using biocompatible polyurethane (PU)-based material. After coating with fibronectin and subsequent culture of 3T3-L1 preadipocytes, the degree of adipocyte differentiation was determined by Oil Red O staining and adipogenic gene expression. We observed that adipocyte differentiation was slightly but substantially affected by culture on various nanogrooved surfaces. In particular, the cell crawling into nanogrooves contributed substantially to an enhanced level of differentiation with higher contact guidance, suggesting that cell-to-surface interactions would play a role for the adipocyte differentiation.

Comparison of orbital prosthesis motility following enucleation or evisceration with sclerotomy with or without a motility coupling post in dogs

OBJECTIVE

To evaluate motility of silicone orbital implants and corneoscleral prostheses, with and without use of a motility coupling post (MCP) in dogs.

ANIMALS STUDIED

Eighteen mixed-breed dogs.

PROCEDURES

The motility of an orbital silicone implant and corneoscleral prosthesis after enucleation (n = 6), evisceration (n = 6), or use of a MCP with evisceration (n = 6) in dogs were compared. One eye from each dog had surgery whereas the opposite eye was used as a control. Clinical evaluations were performed three times a week. Histopathology of the orbital tissues was performed 8 and 12 weeks after surgery.

RESULTS

Implant motility in dogs with evisceration (vertical movement [VM] 8.04 +/- 2.13; horizontal movement [HM] 11 +/- 3.05) and evisceration with MCP (VM 9.61 +/- 1.59); HM was significantly greater than the enucleation group (VM 0.51 +/- 0.5; HM 1.22 +/- 0.68) (P < 0.01). Prosthetic motility in dogs with evisceration with MCP was significantly greater than in dogs with evisceration; dogs with evisceration had significantly greater motility than dogs with enucleation (P < 0.01). No postoperative complications were observed in any of the groups. No significant abnormalities were noted on histopathology.

CONCLUSIONS

MCP placement in silicone orbital implants significantly enhanced the prosthetic motility in dogs. This study supports the use of MCP in silicone orbital implants to enhance corneoscleral prosthesis motility and cosmetics in dogs.

Aryl diketoacids (ADK) selectively inhibit duplex DNA-unwinding activity of SARS coronavirus NTPase/helicase

As anti-HCV aryl diketoacids (ADK) are good metal chelators, we anticipated that ADKs might serve as potential inhibitors of SARS CoV (SCV) NTPase/helicase (Hel) by mimicking the binding modes of the bismuth complexes which effectively competes for the Zn(2+) ion binding sites in SCV Hel thereby disrupting and inhibiting both the NTPase and helicase activities. Phosphate release assay and FRET-based assay of the ADK analogues showed that the ADKs selectively inhibit the duplex DNA-unwinding activity without significant impact on the helicase ATPase activity. Also, antiviral activities of the ADKs were shown dependent upon the substituent. Taken together, these results suggest that there might be ADK-specific binding site in the SCV Hel, which warrants further investigations with diverse ADKs to provide valuable insights into rational design of specific SCV Hel inhibitors.

Selegiline potentiates the effects of EGb 761 in response to ischemic brain injury

We evaluated whether combined treatment with selegiline, a selective MAO-B inhibitor, and EGb 761, a standard extract of Ginkgo biloba, has synergistic effects against ischemic reperfusion injury (IRI) in gerbils. Interestingly, we observed that pretreatment with EGb 761 significantly attenuated selegiline-induced hyperactivity. This finding paralleled striatal fos-related antigen immunoreactivity (FRA-IR) in mice. Four minutes of bilateral carotid artery occlusion caused substantial cell loss in the CA1 of the hippocampus 5 days post-ischemic insult. Pretreatment with EGb 761, with or without selegiline, significantly attenuated this neuronal loss. Combined treatment with EGb 761 plus selegiline was more efficacious in preventing this loss. Synaptosomal formations of protein carbonyl, lipid peroxidation (malondialdehyde (MDA) + 4-hydroxyalkenal (4-HDA)), and reactive oxygen species (ROS) in the hippocampus remained elevated 5 days post-ischemic insult. The antioxidant effects appeared to be most significant in the group treated with EGb 761 plus selegiline. This combined treatment produced more significant attenuation of IRI-induced alterations in intramitochondrial calcium accumulation, the mitochondrial transmembrane potential, and mitochondrial Mn-superoxide dismutase-like immunoreactivity (Mn-SOD-IR) than either treatment alone. Our results suggest that co-administration of EGb 761 and selegiline produces significant neuroprotective effects via suppression of oxidative stress and mitochondrial dysfunction without affecting neurological function.

Enhanced detection of right-to-left shunt through patent foramen ovale by transthoracic contrast echocardiography using harmonic imaging

When the results of transesophageal echocardiography was regarded as the gold standard for detecting a patent foramen ovale (PFO) in 136 consecutive patients referred for evaluation of cardiac source of embolism, transthoracic harmonic imaging using saline contrast was superior to fundamental imaging in accuracy for detecting a PFO (sensitivity, 22.5%; specificity [p < 0.05] and sensitivity, 100%; specificity 100%, respectively.)

Assessment of elastic properties of the descending thoracic aorta by transesophageal echocardiography with acoustic quantification in patients with a stroke

Previous studies have described the use of transesophageal echocardiography (TEE) with acoustic quantification (AQ) in assessing aortic elastic properties. We hypothesized that patients with a prior history of stroke (ST) may have a higher risk of atherosclerotic change in great vessels compared to nonstroke subjects (NST) and thus have decreased elastic properties. We assessed the elastic properties of the descending thoracic aorta (DTA) by TEE in ST patients and compared them with data in NST patients. Subjects included 31 with ST without any evidence of emboli originating from the heart (age 51 +/- 10 years, M:F = 20:11) and 25 age-matched NST (M:F = 8:17). Patients with significant valvular heart disease including aortic and mitral regurgitation, left ventricular dysfunction (ejection fraction < 55%), and congenital heart disease were excluded. Compliance (C), distensibility (D), and stiffness index (SI) were measured using AQ and M-mode measurement at a level of the left atrium. We scored atherosclerotic risk factors (ARF) such as a history of diabetes, hypertension, smoking, hypercholesterolemia, and the presence of atheroma of DTA. There was no evidence of atheroma of DTA in NST. There were no significant differences in heart rate and systolic and diastolic blood pressure between ST and NST patients. Fractional area change (FAC) of DTA was significantly lower in ST than in NST patients (3.2 +/- 1.6 vs 5.4 +/- 2.5%, P = 0.000). ST patients had significantly lower C (1.2 +/- 0.4 vs 1.5 +/- 0.7 x 10(-3) cm2 mmHg(-1), P = 0.039), lower D (0.8 +/- 0.3 vs 1.5 +/- 0.8 x 10(-3) mmHg(-1), P = 0.000), and higher SI (10.3 +/- 8.8 vs 5.3 +/- 2.9, P = 0.006) than NST patients. ST patients without atheroma of DTA (n = 21) also had significantly lower C (1.1 +/- 0.4 vs 1.5 +/- 0.7 x 10(-3) cm2 mmHg(-1), P = 0.038) and lower D (3.5 +/- 1.4 vs 4.8 +/- 2.4 x 10(-3) mmHg(-1), P = 0.021) than NST patients. There was a significant positive correlation between SI and the score of ARF (r = 0.51, P = 0.000). The regional elastic properties of DTA measured by TEE with AQ and M-mode method were abnormal in ST. Therefore, TEE with AQ technique may have a possible clinical application for the detection of early atherosclerotic changes such as alteration of elastic properties in morphological normal DTA.

Enhanced detection of left atrial spontaneous echo contrast by transthoracic harmonic imaging in mitral stenosis

BACKGROUND

Spontaneous echo contrast (SEC) of the left atrium is associated with increased risk of thromboembolism in patients with mitral stenosis (MS). The determination of the presence and severity of left atrial (LA) SEC is of prognostic importance in these patients. Harmonic imaging (HI), a novel echocardiographic technique that differs from conventional fundamental imaging (FI) in that it involves transmitting ultrasound at one frequency and receiving at twice the transmitted frequency, produces better endocardial border definition and myocardial opacification. However, there are no data about its value for the detection of LA SEC. The purpose of this study was to investigate the utility of transthoracic noncontrast tissue HI in the detection of LA SEC in patients with MS.

METHODS

Seventy-four consecutive patients with MS (49 women, mean age 51 years) underwent standard transthoracic echocardiography (TTE) in both HI and FI modes and transesophageal echocardiography (TEE) to determine the presence and severity of LA SEC. Left atrial SEC was graded by TEE as either mild (only seen at high gain) or severe (visible in the entire left atrium at normal gain control of the equipment). The control group comprised 30 patients randomly selected from patients who did not have LA SEC at the TEE examination.

RESULTS

Atrial fibrillation was found in 46 patients (62.2%). The mean mitral valve area and mean mitral gradient were 1.0+/-0.3 cm(2) and 8.2+/-4.1 mm Hg, respectively. Nine patients (12.2%) had episodes of systemic embolism; 8 had stroke, and 1 had peripheral embolism. Left atrial thrombus was found in 11 patients (14.9%) by TEE. Left atrial SEC was present in all but one patient by TEE (mild in 35 patients, severe in 38). Fundamental imaging with TTE, however, revealed LA SEC in only 5 (6.8%) of the 73 patients. In contrast, with HI, LA SEC could be detected in 63 (86.3%) patients. In the detection of severe LA SEC, the sensitivities of FI and HI were 13.2% (5/38) and 100% (38/38), respectively. Left atrial SEC was not observed in control subjects by either FI or HI.

CONCLUSIONS

Transthoracic HI significantly enhances the detection of LA SEC in patients with MS.

Lymphoepithelial carcinoma of the submandibular gland--a case report

A case of lymphoepithelial carcinoma occurring in the left submandibular salivary gland is presented. Histologic features of this rare malignancy are described in detail. This unusual carcinoma has been described frequently in Eskimos and is usually located in the parotid gland. The raised serum IgG to Epstein-Barr virus capsid antigen suggests a causal relationship between Epstein-Barr virus and this type of salivary gland carcinoma.

Distinction between benign and malignant causes of cervical, axillary, and inguinal lymphadenopathy: value of Doppler spectral waveform analysis

OBJECTIVE

Vessels in inflamed lymph nodes are dilated compared with vessels in lymph nodes involved with metastases, which may be compressed by tumor cells. Accordingly, we hypothesized that the Doppler spectral waveform might be different in lymph nodes involved by benign disease and those involved by metastases. We compared spectral waveforms of benign and malignant superficial lymphadenopathy to determine the value of color Doppler sonography in distinguishing between the two.

SUBJECTS AND METHODS

Palpable superficial lymph nodes (41 cervical, one axillary, one inguinal) of 43 untreated patients were prospectively evaluated with color Doppler sonography. We measured resistive index, pulsatility index, peak systolic velocity, and end diastolic velocity from the fastest or next fastest arterial signal in the lymph node that showed the most vigorous flow. Final diagnosis was established by pathologic examination (n = 24) and clinical follow-up (n = 19).

RESULTS

Color Doppler sonography showed blood flow in all cases. The mean resistive index was 0.92 +/- 0.23 in lymph nodes involved with metastases and 0.59 +/- 0.11 in lymph nodes affected by benign processes. The mean pulsatility index was 2.66 +/- 1.59 in lymph nodes involved with metastases and 0.90 +/- 0.23 in lymph nodes affected by benign processes. Lymph nodes involved with metastases showed a characteristic high resistive index (> 1.0) and a high pulsatility index (> 1.5) in 10 of 13 cases. Lymph nodes affected by benign processes showed a low resistive index (< 0.8) and a low pulsatility index (< 1.5) in all cases. The resistive indexes and pulsatility indexes were significantly different (p < .005) between lymph nodes affected by benign versus malignant disease. The mean peak systolic velocity was 25 +/- 11.7 cm/sec in lymph nodes involved with metastases and 24 +/- 16 cm/sec in lymph nodes affected by benign processes. The mean end diastolic velocity was 2 +/- 6.7 cm/sec in lymph nodes involved with metastases and 10 +/- 9.5 cm/sec in lymph nodes affected by benign processes. Although the peak systolic velocities were not significantly different, the end diastolic velocities were significantly different (p < .005) between the two types of lymph nodes.

CONCLUSION

Our results suggest that superficial lymphadenopathy due to benign and malignant diseases can be distinguished with a high degree of accuracy (p < .005) by means of spectral waveform analysis. Color Doppler sonography is a useful adjunct to routine sonography. Lymph nodes with a high resistive index are almost always involved by metastases.