Douglas K. Hanks

Sustained Expression of Homeobox D10 Inhibits Angiogenesis

Homeobox (Hox) genes are master regulatory genes that direct organogenesis and maintain differentiated tissue function. As HoxD3 and HoxB3 promote angiogenesis, we investigated whether endothelial cells use other Hox genes to maintain a mature quiescent phenotype. HoxD10 expression was higher in quiescent as compared to tumor-associated angiogenic endothelium. Microarray analysis of HoxD10-overexpressing endothelial cells revealed a pattern of gene expression consistent with a nonangiogenic phenotype. Moreover, sustained expression of HoxD10 impaired endothelial cell migration and blocked angiogenesis induced by basic fibroblast growth factor and vascular endothelial growth factor in the chick chorioallantoic membrane in vivo. HoxD10-overexpressing human endothelial cells also failed to form new vessels when implanted into immunocompromised mice. These results indicate a role for HoxD10 in maintaining a nonangiogenic state in the endothelium.

Sono-Urethrography in the Evaluation of Anterior Urethral Strictures

During a 7-year period 123 paired urethrographic and sono-urethrographic studies were performed on 101 patients with 110 urethral strictures. In all but 3 cases the urethra was subsequently evaluated either cystoscopically or at open operation. Sono-urethrography readily identified urethral calculi, diverticula and false passages. It correctly identified the stricture and its site in every case. There was a significant difference between stricture length as measured by urethrography compared to that measured by sono-urethrography (p < 0.003). However, if the strictures were grouped based on anatomical location, there was good correlation and no significant difference in the penile urethra (correlation coefficient = 0.94, p = 0.74) but poor correlation and the significant difference remained in the urethral bulb (correlation coefficient = 0.64, p < 0.007). Similarly, when urethrographic and sono-urethrographic stricture lengths were compared with operative lengths, in the penile urethra the correlation coefficients were close (correlation coefficient = 0.91 versus 0.98) but in the urethral bulb the poor correlation persisted (correlation coefficient = 0.69 versus 0.89). Although sono-urethrography certainly identifies periurethral tissue, it was unreliable in predicting the depth of spongiofibrosis when compared with full depth biopsies in 36 patients with histopathological correlation. Finally, in 16% of the patients sono-urethrography correctly indicated a reconstructive procedure different from that originally suggested by conventional urethrography. Sono-urethrography is a dynamic 3-dimensional study that accurately identifies stricture site, number and caliber. Compared with conventional urethrography, it more accurately measures stricture length and diameter, and identifies periurethral tissue, making it a valuable adjunct in the evaluation of patients with suspected anterior urethral strictures.

Lymphoepithelioma-like carcinoma of the lung: radiologic features of an uncommon primary pulmonary neoplasm.

OBJECTIVE The purpose of this study was to review the chest radiographic, CT, and MRI appearances of primary pulmonary lymphoepithelioma-like carcinoma (LELC). CONCLUSION Primary pulmonary LELC is histopathologically identical to nasopharyngeal carcinoma. The radiographic, CT, and MRI features of primary pulmonary LELC are nonspecific, often resembling those of bronchogenic carcinoma. Primary pulmonary LELC usually presents as a poorly circumscribed, enhancing, peripheral solitary pulmonary nodule on CT; necrosis may be present and is considered a poor prognostic sign. MRI shows isointense to low-intensity signal on T1-weighted images and mildly increased signal on T2-weighted images; enhancement of abnormal tissue is typical. Most patients present with early-stage disease. Primary pulmonary LELC should be suspected in selected patients and requires differentiation from bronchogenic carcinoma and metastatic nasopharyngeal carcinoma.

Sevoflurane degradation by carbon dioxide absorbents may produce more than one nephrotoxic compound in rats.

PurposeDegradation of sevoflurane by carbon dioxide absorbents produces compound A, a vinyl ether. In rats, compound A can produce renal corticomedullary necrosis. We tested whether other compounds produced by sevoflurane degradation also could produce corticomedullary necrosis.MethodsTwo groups of rats were exposed for four hours to sevoflurane 2.5% delivered through a container filled with fresh Sodasorb® and heated to 30∘C or to 50∘C, respectively. Compound A was added to produce an average concentration of 120 ppm in both groups. A third (control) group received 2.5% sevoflurane that did not pass through absorbent, and no compound A was added.ResultsAs determined by gas chromatography, the higher temperature produced more volatile breakdown products, including compound A. Median necrosis of the corticomedullary junction in the 50∘C group [10% (quartiles 1.096-7.8%); n = 20] exceeded that in the 30∘C group [5% (6.5%-15%); n = 18;P < 0.02], and both exceeded the median necrosis in the control group [0% (0.096-0.2%);n = 10;P < 0.02], The respective mean ± SD values for these three studies were: 12.8 ± 16.7%, 5.3 ± 4.4%, and 0.3 ± 0.5%.ConclusionDegradation products of sevoflurane other than compound A can cause or augment the renal injury in rats produced by compound A.RésuméObjectifLa dégradation du sévoflurane par les absorbants de gaz carbonique produit un éther vinylique, le composé A. Chez les rats, ce composé provoque une nécrose corticomédullaire rénale. Nous avons vérifié si d’autres composés issus de la dégradation du sévoflurane peuvent aussi provoquer cette nécrose.MéthodeDeux groupes de rats ont été exposés pendant quatre heures à du sévoflurane à 2,5 % administré après avoir traversé un récipient rempli de Sodasorb® frais et chauffé respectivement à 30° C ou à 50°C. Du composé A a été ajouté pour produire une concentration moyenne de 120 ppm dans les deux groupes. Un troisième groupe (témoin) a reçu du sévoflurane à 2,5 %, qui ne traversait pas l’absorbant, et sans ajout de composé A.RésultatsLes résultats de la Chromatographie en phase gazeuse ont montré que sous la température la plus élevée, il y a eu plus de produits de dégradation volatils, y compris le composé A. Dans le groupe 50°C, la nécrose moyenne de la jonction corticomédullaire dépassait [10 % (quartiles 1,0 %-7,8 %); n = 20] celle du groupe 30°C [5 %(6,5%- 15%);n = 18; P < 0,02] et les deux étaient plus élevée que celle du groupe témoin [0 % (0,0%-0,2 %); n = 10; P < 0,02]. Les valeurs respectives de la moyenne ± l’écart type ont été de 12,8 ± 16,7%, 5,3 ± 4,4 % et de 0,3 ± 0,5 %.ConclusionLes produits de dégradation du sévoflurane, autres que le composé A, peuvent causer ou augmenter la lésion rénale produite par le composé A chez les rats.

Minute pulmonary meningothelial-like nodules: thin-section CT appearance.

Minute pulmonary meningothelial-like nodules are often incidentally discovered during pathologic evaluation of pulmonary parenchymal specimens. These lesions were once thought to represent pulmonary chemodectomas, but pathological studies have shown that they are not of neuroendocrine origin. Minute pulmonary meningothelial-like nodules are benign, perhaps reactive in nature, but are occasionally found in association with lung carcinoma. They may appear as randomly distributed well-defined micronodules on thin-section chest CT, and thus may simulate metastatic disease when associated with lung carcinoma.

Sarcoidosis presenting as an enlarging solitary pulmonary nodule.

Sarcoidosis is generally not considered in the differential diagnosis of solitary pulmonary nodules. We recently encountered a case in which preoperative awareness of this presentation of sarcoidosis allowed a limited pulmonary resection with resultant lower morbidity and potential preservation of lung function to be performed. Although rare, sarcoidosis should be considered in the differential diagnosis of solitary pulmonary nodules.

Coccidioidomycosis presenting as midline neck mass.

Coccidioidomycosis is a disease caused by a dimorphic fungus, Coccidioidomycosis immitis. This fungus is endemic in the dry desert regions of the southwestern United States and Mexico. The fungal spores grow in soil after a rainfall; arid climates facilitate inhalation via the dispersion of the spores after the soil dries. Approximately 60% of pulmonary infections go undetected due to a lack of symptoms. Most commonly, patients will present with cough, headache, or fever, but head and neck manifestations are uncommon. The symptoms known as “valley fever,” include arthralgias, fever, and skin lesions that can be maculopapular or progress to erythema nodosum. However, a small percentage of patients can develop disseminated disease that is potentially fatal and can involve meninges, bone, joints, skin, or soft tissue. Clinical manifestations are protean; the primary disease can simulate many other bacterial, mycotic, or disseminated neoplastic diseases. Cavitary lesions may simulate tuberculosis, particularly when the lesions involve the upper lobes of the lungs. Otolaryngologists should increase their awareness of this disease and its presentation as a solitary neck mass in order to more expediently diagnose and treat their patients. A 52-year-old female in her usual state of health presented to the otolaryngology clinic with a 1-month history of increasing pain, erythema, and a suprasternal neck mass. She denied fevers, cough, hemoptysis, or associated systemic symptoms. She denied that any other family members were sick. She is a native of the Canton province of China but had lived in San Francisco for 8 years with no travel to the Central Valley region which encompasses the central part of California from Shasta County to Kern County. She

Think global, act local: chronic dysuria and sterile pyuria in an Eritrean-American woman

A 70-year-old female Eritrean immigrant living in the USA presented with classic findings of genitourinary (GU) tuberculosis (TB), including risk of tuberculosis exposure based on country of origin, chronic urinary tract symptoms and persistent sterile pyuria despite antibacterial therapy. Furthermore, this patient had the hallmark radiographical findings of ureteral stricture, a dilated pelvic calyceal system, hydroureteronephrosis and bladder wall thickening, as well as a bladder wall biopsy that revealed granulomatous disease. The patient was evaluated multiple times over the course of 3 years in outpatient and inpatient medical settings before a diagnosis was made and appropriate treatment initiated. As with many cases of GU TB, a protracted diagnosis allowed for advanced disease progression and significant morbidity from obstructive uropathy and chronic kidney disease.