When to sweat: A history of chemotherapy in malignant sweat gland tumors. A unique case report and literature review

Sarcomatoid sweat gland carcinomas are rare among cutaneous cancers, with less than 20 cases described. A 54-year-old woman with sarcomatoid sweat gland carcinoma of the right upper extremity suffered extensive recurrence at 15 months, unresponsive to chemotherapy. There is no standard treatment or chemotherapy regimens for metastatic sweat gland carcinoma.

Sarcomatoid Eccrine Porocarcinoma in a Patient with Urothelial Carcinoma

Introduction/Objective

Sarcomatoid porocarcinoma of skin is an exceedingly rare and diagnostically challenging malignancy of the sweat gland. In this report, we describe a rare case of a sarcomatoid eccrine porocarcinoma initially diagnosed to be a squamous cell carcinoma (SCC) in a patient with metastatic urothelial carcinoma (UC).

Methods/Case Report

Our patient is a 60 year old male with stage IV, poorly differentiated UC status post TURBT with residual tumor, and a 4 x 3 x 1 cm, polypoid, ulcerating skin nodule on his right cheek presumptively diagnosed to be an SCC on biopsy at an outside hospital. Given the concern that this cutaneous lesion may be a metastatic UC with squamous differentiation, the skin nodule was re-biopsied at our hospital. On histology, the lesion consisted of sheets of squamoid, polygonal cells in the dermis with pleomorphic nuclei showing irregular contours, prominent nucleoli, coarse chromatin, and frequent mitoses. The tumor was focally connected to the epidermis, which established it as a primary skin neoplasm and not a metastatic lesion. The tumor cells stained diffusely positive for vimentin, AE1/AE3, CK5/6, HMW CK, CK7, p63, and p16, negative for CK20, GATA-3, BerEP4, and Sox10, and showed high Ki67 proliferation index. Within the tumor sheets were poorly formed, focal ductal elements that stained positive for CAM5.2, EMA, CEA, and CK19, and negative for p63. The tumor showed comedo necrosis, epidermal ulceration, and no keratinization. The tumor was diagnosed to be a porocarcinoma given its positive staining for CK7 and p16, presence of focal ductal elements, and epidermal connection, with sarcomatoid features indicated by strong vimentin expression.

Results (if a Case Study enter NA)

NA.

Conclusion

In this report, we described an exceedingly rare, diagnostically challenging case of a sarcomatoid porocarcinoma initially suspected to be a cutaneous SCC or metastatic UC with squamous differentiation. Although the tumor cells morphologically resembled SCC, its positive staining for CK7 and p16, presence of ductal elements, and lack of keratinization, favored a diagnosis of porocarcinoma rather than cutaneous SCC. Its focal connection to the epidermis and lack of GATA-3 expression favored a primary skin neoplasm rather than a metastatic UC. Its sarcomatoid nature was indicated by strong vimentin expression. Sarcomatoid porocarcinoma is diagnostically challenging given its rarity and potential to mimic other cutaneous malignancies such as SCC.

Metastasis of a Primary Sinonasal Alveolar Rhabdomyosarcoma to the Testicle in an Adult Patient

Introduction/Objective

Alveolar rhabdomyosarcoma is an aggressive tumor of skeletal muscle differentiation that predominantly affects adolescents and young adults, and is rare over 45 years of age. It has poor prognosis with metastasis, and most commonly spreads to the lymph nodes, bone marrow, and lungs. In this report, we describe a middle-aged patient with a primary sinonasal alveolar rhabdomyosarcoma which metastasized to the right testicle, an unusual metastatic site reported only a few times in literature.

Methods/Case Report

Our patient is a 53 year old male who presented in 2020 with recurrent epistaxis and bilateral cervical lymphadenopathy over a 2 month period. Maxillofacial CT/MRI imaging revealed a 4-cm sized mass within the left nasal cavity eroding into the ethmoid sinuses. The patient underwent endoscopic sinus surgery of the sinonasal mass, which on histology, appeared as poorly differentiated small round blue cells with numerous mitoses infiltrating as single cells and nests. These cells stained positive for vimentin, myogenin, desmin, and CD56, and negative for AE1/AE3, chromogranin, S-100, CD99, and CD45. The cells showed very high Ki67 proliferation index (70-80%) and tested positive for FOXO1 gene rearrangement, which supported the diagnosis of alveolar rhabdomyosarcoma. The patient completed chemoradiation therapy, and MRI scans over the next 2 years were negative for residual sinonasal tumor. However, the patient returned in 2022 after having undergone a right orchiectomy at an outside hospital for testicular pain, and abdominal CT showed diffuse retroperitoneal lymphadenopathy concerning for metastasis. On histology, the resected testicle showed seminiferous tubules infiltrated and destroyed by sheets of poorly differentiated small round blue cells with fibrous septae separating the nests of tumor cells into alveolar-like spaces with central loss of cohesion. The tumor cells showed the same immunohistochemical staining pattern as the primary sinonasal lesion, thus confirming it to be metastatic alveolar rhabdomyosarcoma.

Results (if a Case Study enter NA)

NA.

Conclusion

It is unusual for alveolar rhabdomyosarcomas to occur in adults over 45 years old, and is even rarer for these tumors to metastasize to the testicle. Metastases also only account for 1% of testicular tumors. Our report documents a very rare case of an alveolar rhabdomyosarcoma in a middle-aged adult which metastasized to the testicle after chemoradiation therapy.

Two Cases of Duodenal Neuroendocrine (Carcinoid) Tumor Concurrent with Invasive Gastric Adenocarcinoma and Pancreatic Intraductal Papillary Mucinous Neoplasm

Introduction/Objective

Neuroendocrine (carcinoid) tumors of the duodenum are extremely rare and account for only 2-4% of gastrointestinal tract neuroendocrine tumors. We report two cases of incidentally discovered duodenal neuroendocrine tumor which respectively occurred in a patient with invasive gastric adenocarcinoma and in a patient with pancreatic intraductal papillary mucinous neoplasm (IPMN).

Methods/Case Report

The first case involved a 60-year old male who presented with melena and symptomatic anemia and was found on EGD to have a large circumferential mass at the gastric antrum/pylorus, which was revealed to be an invasive gastric adenocarcinoma on biopsy. At the time of distal gastrectomy for this malignancy, a concurrent, 0.6 cm-sized, low grade neuroendocrine tumor was incidentally discovered at the duodenal margin. The duodenal tumor consisted of nests and trabeculae of monotonous cells with ovoid/round nuclei, finely speckled “salt and pepper” chromatin, and low mitotic rate (< 2 mitoses/2 mm2), and invaded only into submucosa. The tumor cells were strongly and diffusely positive for neuroendocrine markers chromogranin, synaptophysin, and CD56, positive for CK7 and CDX2, negative for CK20, and with low Ki67 proliferation index (< 3%). The second case involved a 69-year old female who presented with epigastric pain and was found on abdominal CT to have a 4 cm-sized cystic mass in the pancreatic head. While biopsy of the pancreatic mass revealed an IPMN, a separate biopsy of an incidentally discovered, 1 cm-deep ulcer in the duodenum bulb revealed a low-grade neuroendocrine tumor with similar morphologic features, mitotic rate, and immunohistochemical staining pattern as the prior case while also negative for IMP3 stain. The patient had normal serum gastrin and urine HIAA levels, but elevated serum chromogranin-A levels.

Results (if a Case Study enter NA)

NA.

Conclusion

Duodenal carcinoids are rare (1-3% of primary duodenal tumors) and are mostly non-functional and unifocal. The duodenum is also the least common site (2-4%) for GI tract neuroendocrine tumors. The pathophysiology of these tumors is still poorly understood, with the majority occurring sporadically and a minority in the setting of hereditary cancer syndromes. This report documents two very rare instances of duodenal neuroendocrine tumor incidentally discovered with invasive gastric adenocarcinoma and pancreatic IPMN.

Biphasic Sarcomatoid Sweat Gland Carcinoma With Ductal Epithelial And Spindled Myoepithelial Cell Components (Malignant Mixed Tumor Of Skin)

Introduction/Objective

Sweat gland carcinomas are a group of malignant skin adnexal tumors that are difficult to diagnose due to their rarity, wide morphologic variation, and limited literature on diagnosis and classification. These tumors may appear bland and morphologically resemble benign skin adnexal tumors, or may appear poorly differentiated and mimic metastatic carcinoma especially from a breast primary. Biphasic sweat gland carcinomas are an even rarer entity, with only few cases reported in literature, and have been described to consist of a well- differentiated ductal epithelial component and a poorly differentiated, sarcomatoid, spindle cell component.

Methods/Case Report

Our case report describes a 53 year old female referred to our institution for diagnosis of an excised skin lesion of the right upper arm, which had been slowly growing for 8 years. The histology revealed a biphasic malignant neoplasm involving the dermis and subcutis. The tumor consisted of an epithelial cell component with glandular and squamoid morphology and positive for CK5/6, CK7, and CAM5.2, and a spindled myoepithelial cell component with sarcomatoid morphology and positive for S100, vimentin, and p63. Stains for CK20, ER, PR, PAX8, CEA, and TTF1 were negative. The histological and clinical findings favored a primary skin adnexal tumor, rather than a metastatic lesion.

The patient underwent wide local excision of the lesion given that margins of the original excision were indeterminate. The histology of this re-excision demonstrated the same biphasic tumor with ductal epithelial and sarcomatoid myoepithelial cell components positive for the same stains. Although margins were negative in this re-excision, 3-4 months later, the patient developed dyspnea with multiple new pulmonary and hilar masses discovered on imaging, and new-onset headache with a frontal lobe mass discovered on brain imaging. These masses were biopsied/resected, and revealed to be metastases of the original cutaneous tumor positive for the same markers.

Results (if a Case Study enter NA)

NA

Conclusion

This case report describes a rare, diagnostically challenging case of a biphasic sweat gland carcinoma with ductal epithelial and sarcomatoid myoepithelial cell components, which demonstrated aggressive behavior with distant metastasis. These tumors are a clinicopathological quandary given their rarity and the paucity of literature on their characterization.

Visualization of in vitro deep blood vessels using principal component analysis based laser speckle imaging

Visualization of blood vessels is a fundamental task in the evaluation of the health and biological integrity of tissue. Laser speckle contrast imaging (LSCI) is a non-invasive technique to determine the blood flow in superficial or exposed vasculature. However, the high scattering of biological tissue hinders the visualization of those structures. In this paper, we propose the use of principal component analysis (PCA) in combination with LSCI to improve the visualization of deep blood vessels by selecting the most significant principal components. This analysis was applied to in vitro samples, and our results demonstrate that this approach allows for the visualization and localization of blood vessels as deep as 1000 μm.

Use of kurtosis for locating deep blood vessels in raw speckle imaging using a homogeneity representation

Visualization of deep blood vessels in speckle images is an important task as it is used to analyze the dynamics of the blood flow and the health status of biological tissue. Laser speckle imaging is a wide-field optical technique to measure relative blood flow speed based on the local speckle contrast analysis. However, it has been reported that this technique is limited to certain deep blood vessels (about ? = 300 ?? ? m ) because of the high scattering of the sample; beyond this depth, the quality of the vessel’s image decreases. The use of a representation based on homogeneity values, computed from the co-occurrence matrix, is proposed as it provides an improved vessel definition and its corresponding diameter. Moreover, a methodology is proposed for automatic blood vessel location based on the kurtosis analysis. Results were obtained from the different skin phantoms, showing that it is possible to identify the vessel region for different morphologies, even up to 900 ?? ? m in depth.

Osciladores Caóticos implementados en Microcontrolador PIC18F

Introducción: Recientemente, los sistemas caóticos han llamado la atención de la comunidad científica internacional, debido a sus potenciales aplicaciones en varias ramas de la ciencia e ingeniería. Se han propuesto muchos trabajos con el fin de resolver algunos problemas interesantes, como la determinación de daños estructurales en los materiales o en sistemas de comunicaciones seguras. Sin embargo, la mayoría de estos trabajos se enfocan en sistemas caóticos en tiempo continuo, mientras que en muchos casos, es deseable que estos sistemas estén en el modo de tiempo discreto y puedan ser utilizados en tiempo real.                      Método: El presente trabajo propone la implementación experimental de tres osciladores caóticos discretizados en un microcontrolador simple. Los osciladores caóticos a implementar son muy conocidos y muy utilizados para ejemplificar posibles soluciones a diversos problemas: los osciladores de Lorenz, Rössler y Chen. Para lo cual, se utilizan tan solo un microcontrolador de bajo costo, unos cuantos resistores y un algoritmo de computación sencillo.Resultados: Se obtiene un sistema embebido de bajo costo y sencillo para implementar osciladores caóticos discretizados.                     Discusión o Conclusión: Se demuestra que los osciladores caóticos de Lorenz, Rössler y Chen pueden implementarse en cualquier microcontrolador de arquitectura basada en palabras de 18 bits o más. Además, se observa que el algoritmo propuesto se pude migrar de un oscilador a otro con solo sustituir el sistema caótico de ecuaciones.

Identification and analysis of murine pancreatic islet enhancers

AIMS/HYPOTHESIS

The paucity of information on the epigenetic barriers that are blocking reprogramming protocols, and on what makes a beta cell unique, has hampered efforts to develop novel beta cell sources. Here, we aimed to identify enhancers in pancreatic islets, to understand their developmental ontologies, and to identify enhancers unique to islets to increase our understanding of islet-specific gene expression.

METHODS

We combined H3K4me1-based nucleosome predictions with pancreatic and duodenal homeobox 1 (PDX1), neurogenic differentiation 1 (NEUROD1), v-Maf musculoaponeurotic fibrosarcoma oncogene family, protein A (MAFA) and forkhead box A2 (FOXA2) occupancy data to identify enhancers in mouse islets.

RESULTS

We identified 22,223 putative enhancer loci in in vivo mouse islets. Our validation experiments suggest that nearly half of these loci are active in regulating islet gene expression, with the remaining regions probably poised for activity. We showed that these loci have at least nine developmental ontologies, and that islet enhancers predominately acquire H3K4me1 during differentiation. We next discriminated 1,799 enhancers unique to islets and showed that these islet-specific enhancers have reduced association with annotated genes, and identified a subset that are instead associated with novel islet-specific long non-coding RNAs (lncRNAs).

CONCLUSIONS/INTERPRETATIONS

Our results indicate that genes with islet-specific expression and function tend to have enhancers devoid of histone methylation marks or, less often, that are bivalent or repressed, in embryonic stem cells and liver. Further, we identify a subset of enhancers unique to islets that are associated with novel islet-specific genes and lncRNAs. We anticipate that these data will facilitate the development of novel sources of functional beta cell mass.

Ba2YCu3O6.9 Powder Preparation by Sol-Gel Emulsion Techniques

Barium yttrium cuprate powders were prepared by a sol-gel emulsion process in which an aqueous nitrate solution containing Ba, Y, and Cu in the correct stoichiometry was emulsified in heptane. The resulting micrometer-sized droplets were gelled by adding a high-molecular-weight primary amine that extracts nitric acid from the aqueous phase and raises the pH of the droplets. Thermal gravimetric analysis revealed that the correct overall stoichiometry was obtained at temperatures lower than 400 °C during calcination, but X-ray diffraction showed that calcination at temperatures greater than 800° may be required to produce the correct phase. One possible advantage of this technique is the control of powder morphology on a micrometer scale so that powders can be prepared for advanced ceramics processing methods. Also, segregation of components, if any, will be restricted to distances less than one micrometer.

Comparison of IOP Measurements Between ORA and GAT in Normal Chinese

PURPOSE

To compare intraocular pressure (IOP) obtained from the ocular response analyzer (ORA) and Goldmann applanation tonometer (GAT) on a group of normal Chinese.

METHODS

One hundred twenty-five normal subjects were recruited, with one eye randomly selected for this study. Each eye was measured first with the noncontact tonometer ORA, followed by the GAT and ultrasound pachometry, in a randomized order. Four readings were obtained from the ORA, and three measurements were taken with the GAT. The mean was used for analysis. The ORA provided a Goldmann-correlated IOP (IOPg) and a corneal-compensated IOP (IOPcc). Three central corneal thickness (CCT) values were measured using an ultrasound pachometer, and the mean was used for analysis.

RESULTS

IOP obtained from the ORA was similar to that from the GAT (IOPg minus GAT: mean difference = 0.33 mm Hg, 95% limits of agreement = 4.55 to -4.44 mm Hg; IOPcc minus GAT: mean difference = 0.24 mm Hg, 95% limits of agreement = 4.83 to -5.07 mm Hg). CCT was positively associated with corneal hysteresis (CH) (r2 = 0.30, p < 0.01), corneal resistance factor (r2 = 0.38, p < 0.01), GAT (r2 = 0.09, p < 0.01) and IOPg (r2 = 0.16, p < 0.01). IOPcc was not associated with CCT (r2 = 0.01, p = 0.33).

CONCLUSIONS

Both IOPg and IOPcc have good agreement with GAT on normal subjects. The influence of CCT on IOPcc was insignificant.

Effects of a p38 MAP kinase inhibitor on bone ingrowth and tissue differentiation in rabbit chambers

The effects of an oral p38 mitogen-activated protein kinase (MAPK) inhibitor and polyethylene particles separately and together on tissue differentiation in the bone harvest chamber (BHC) in rabbits over a 3-week treatment period were investigated. The harvested tissue was analyzed histomorphometrically for markers of bone formation (percentage of bone area), osteoblasts (alkaline phosphatase staining), and osteoclasts (CD51, the alpha chain of the vitronectin receptor). Polyethylene particles decreased the percentage of bone ingrowth and staining for alkaline phosphatase. The p38 MAPK inhibitor alone decreased alkaline phosphatase staining. When the oral p38 MAPK inhibitor was given and the chamber contained polyethylene particles, there was a suppression of bone ingrowth and alkaline phosphatase staining. In contrast to oral non-steroidal anti-inflammatory drugs (NSAIDs) and local Interleukin-1 receptor antagonist (IL-1ra) administration, the oral p38 MAPK inhibitor alone did not suppress bone formation when given during the initial phase of tissue differentiation. Particle-induced inflammation and the foreign body reaction were not curtailed when the p38 MAPK inhibitor was given simultaneously with particles. Additional experiments are needed to establish the efficacy of p38 MAPK inhibitor administration on mitigating an established inflammatory and foreign body reaction that parallels the clinical situation more closely.

The influence of corneal properties on rebound tonometry

PURPOSE

To determine the influence of corneal thickness, corneal hysteresis (CH), and corneal resistance factor (CRF) on intraocular pressure (IOP) measurements obtained using the iCARE rebound tonometer.

DESIGN

Cross-sectional study.

PARTICIPANTS

One hundred twenty-five eyes of 125 normal healthy subjects.

METHODS

Intraocular pressure was determined in all subjects using the iCARE at both central and temporal corneal regions. Corneal thickness at these 2 regions was determined by ultrasonic pachymetry. Corneal hysteresis and corneal resistance factor were measured using an ocular response analyzer. Goldmann applanation tonometry (GAT) was also performed on all eyes.

MAIN OUTCOME MEASURES

Intraocular pressure, corneal thickness, corneal hysteresis, and corneal resistance factor.

RESULTS

Although the peripheral cornea was significantly thicker than the central cornea, IOPs obtained by the iCARE at the 2 regions were similar and significantly higher than GAT measurements. There were an overestimation at higher IOPs and an underestimation at lower IOPs relative to GAT measurements. Multiple regression analysis showed a significant correlation between the iCARE and CH (partial correlation r = -0.67, P<0.01) and CRF (partial correlation r = 0.82, P<0.01). The correlation between the iCARE and central corneal thickness was not significant.

CONCLUSIONS

Rebound tonometry is affected by corneal properties including CH and CRF but not corneal thickness.

Synaptic complex formation of two retrovirus DNA attachment sites by integrase: a fluorescence energy transfer study

The integration of retroviral DNA by the viral integrase (IN) into the host genome occurs via assembled preintegration complexes (PIC). We investigated this assembly process using purified IN and viral DNA oligodeoxynucleotide (ODN) substrates (93 bp in length) that were labeled with donor (Cy3) and acceptor fluorophores (Cy5). The fluorophores were attached to the 5' 2 bp overhangs of the terminal attachment (att) sites recognized by IN. Addition of IN to the assay mixture containing the fluorophore-labeled ODN resulted in synaptic complex formation at 14 degrees C with significant fluorescence resonance energy transfer (FRET) occurring between the fluorophores in close juxtaposition (from approximately 15 to 100 A). Subsequent integration assays at 37 degrees C with the same ODN (32P-labeled) demonstrated a direct association of a significant FRET signal with concerted insertion of the two ODNs into the circular DNA target, here termed full-site integration. FRET measurements (deltaF) show that IN binds to a particular set of 3' OH recessed substrates (type I) generating synaptic complexes capable of full-site integration that, as shown previously, exhibit IN mediated protection from DNaseI digestion up to approximately 20 bp from the ODN att ends. In contrast, IN also formed complexes with nonspecific DNA ends and loss-of-function att end substrates (type II) that had significantly lower deltaF values and were not capable of full-site integration, and lacked the DNaseI protection properties. The type II category may exemplify what is commonly understood as "nonspecific" binding by IN to DNA ends. Two IN mutants that exhibited little or no integration activity gave rise to the lower deltaF signals. Our FRET analysis provided the first direct physical evidence that IN forms synaptic complexes with two DNA att sites in vitro, yielding a complex that exhibits properties comparable to that of the PIC.

Effect of instrument rotation on handheld keratometry

PURPOSE

To study the effect of instrument rotation on handheld automated keratometry.

SETTING

Department of Optometry and Radiography, The Hong Kong Polytechnic University, Hong Kong SAR, China.

METHODS

In 33 recruited subjects, corneal curvature in 1 eye (randomly selected) was measured using a Medmont topographic keratometer and a Nidek handheld keratometer. In handheld keratometry, measurements were obtained holding the instrument in the upright position and rotating it anticlockwise 5 degrees, 10 degrees, and 15 degrees and then clockwise 5 degrees, 10 degrees, and 15 degrees. The sequence of measurements was randomly assigned. The steepest and flattest corneal curvatures as well as the axis along the flattest meridian were compared in different conditions. The corneal power was converted to vector representation (M, J0, J45) for a second comparison.

RESULTS

There was a significant difference in the steepest and flattest curvatures in different conditions (repeated-measures analysis of variation, P<.05). However, the mean difference between handheld and topographic keratometry was approximately 0.25 diopter (D) for the steepest curvature and 0.05 D for the flattest curvature regardless of the direction and amount of rotation. The intraclass correlation coefficients were nearly 1, which indicated good clinical reliability. The mean difference in axis determination followed the direction and amount of rotation. With vector representation, the difference between the devices increased with the amount of rotation, especially J0 and J45.

CONCLUSIONS

Handheld keratometry was in agreement with topographic keratometry. However, practitioners should adjust the axis manually according to the direction and amount of rotation. The difference between handheld and topographic keratometry increased with the rotational effect, which was seen with vector representation. Practitioners are advised to use the handheld keratometer in the upright position.

Avian retrovirus integrase-enhanced transgene integration into mammalian cell DNA in vivo

Systems for introducing DNA genes-of-interest into mammalian cellular genomes have ranged from the use of different physical techniques to viruses including retroviruses. We have developed a microinjection method for an efficient and permanent integration of a DNA transgene into the cell genome by use of the retrovirus integrase. A 3.0-kb linear DNA fragment containing an internal herpes simplex virus thymidine kinase gene (tk) with flanking avian retrovirus U5 and U3 terminal attachment sites (U5-pgk/tk-U3) recognized by the integrase was constructed. The other donor, a 3.3-kb linear DNA fragment containing the same gene (pgk/tk) flanked by ApaL1 restriction sites not recognized by integrase, was also produced. After assembly of integrase-transgene complexes on ice, the complexes were microinjected into the nucleus of human fibroblast cells (143Btk) containing a defective thymidine kinase. The number of hypoxanthine/aminopterin/thymidine (HAT)-resistant colonies produced upon microinjection of either naked DNA or the independently assembled integrase-transgene complexes were determined. Our data suggests that enhanced integration of U5-pgk/tk-U3 required the DNA attachment sites and co-delivery of integrase. The data was consistent with a direct role for both of these elements in producing an approximate 4-fold increase in the number of HAT-resistant colonies observed over microinjection of just naked U5-pgk/tk-U3 (P < 0.0001).

Effect of posture and artificial tears on corneal power measurements with a handheld automated keratometer

PURPOSE

To study the effect of posture and artificial tears on handheld automated keratometry.

SETTING

Department of Optometry and Radiography, Hong Kong Polytechnic University, Hong Kong, China.

METHODS

Thirty-five subjects were recruited to have corneal curvature measurement in 1 eye (randomly selected) by a Medmont topographic keratometer and a Nidek handheld keratometer. In handheld keratometry, the measurements were taken with the subject in a sitting and lying posture (both with and without the use of artificial tears). The sequence of measurements was randomly assigned, but the application of artificial tears was always the last. The steepest and flattest corneal curvatures were compared between the 4 conditions. The corneal power was converted to orthogonal power vector components and rectangular Fourier form (M, J(0), J(45)) for another comparison.

RESULTS

There was a significant difference in the steepest and flattest meridians between the 4 conditions (P<.01). However, the mean difference between the handheld keratometer and the topographic keratometer was less than 0.50 diopter, and the intraclass correlation coefficient (ICC) was very high (0.96), indicating good clinical reliability. When analyzed in rectangular Fourier form, the difference was also significant but the ICCs were lower (0.97, 0.89, and 0.64 for M, J(0), and J(45), respectively). The greatest difference was when subjects were in the lying posture and had received artificial tears.

CONCLUSIONS

Handheld keratometry provided different results from topographic keratometry. The difference was greatest with the use of artificial tears. Cataract surgeons should take this into consideration, especially when using the handheld keratometry in the operating theater in patients under general anesthesia. Results show that the power vector method is best for studying corneal shape.

Renin-angiotensin system blockade in biopsy-proven allograft nephropathy

Allograft nephropathy leads to progressive renal injury and ultimate graft loss. In native kidney disease, the use of angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB) is beneficial in retarding the decline of renal function. We reviewed a cohort of renal transplant recipients who were prescribed either an ACEi or ARB for biopsy-proven allograft nephropathy. Patients were followed from time of initiation of ACEi/ARB and were stratified based on biopsy findings. Outcomes of interest included safety, allograft survival, renal function, and rate of renal function decline pre- and post-ACEi/ARB. The 5-year allograft survival after biopsy was 83%. Mean serum creatinine was 2.2 +/- 1.1 mg/dL (range 1.0 to 4.3) at time of biopsy and 2.6 +/- 1.2 mg/dL (1.2 to 6.5) at last follow-up. The mean slope of the creatinine versus time (SD) was 2.43 (7.93) in the 12 months prior to therapy and 1.45 (3.66) following therapy, with the absolute difference in slope -3.38 (6.06) (P =.0004). We conclude that treatment with ACEi/ARB is beneficial in the management of allograft nephropathy.

Regulation of the Expression of the Prostate-specific Antigen by Claudin-7

Claudins are a family of proteins involved in forming tight junctions between cells. Here we describe two forms of claudin-7 (CLDN-7), a full-length form of CLDN-7 with 211 amino-acid residues and a C-terminal truncated form with 158 amino-acid residues. These two forms of CLDN-7 are able to regulate the expression of a tissue-specific protein, the prostate-specific antigen (PSA), in the LNCaP prostate cancer cell line. We also found that the expression of CLDN-7 is responsive to androgen stimulation in the LNCaP cell line, suggesting that this protein is involved in the regulatory mechanism of androgen. Both forms of claudin-7 are expressed in human prostate, kidney and lung samples, and in most samples, the full-length form of claudin-7 was predominant. However, in some prostate samples from healthy individuals, the truncated form of claudin-7 is predominantly expressed. Our results demonstrated that unlike other claudins, CLDN-7 has both structural and regulatory functions, and the two forms of CLDN-7 may be related to cell differentiation in organ development.

Molecular and genetic determinants of rous sarcoma virus integrase for concerted DNA integration

Site-directed mutagenesis of recombinant Rous sarcoma virus (RSV) integrase (IN) allowed us to gain insights into the protein-protein and protein-DNA interactions involved in reconstituted IN-viral DNA complexes capable of efficient concerted DNA integration (termed full-site). At 4 nM IN, wild-type (wt) RSV IN incorporates approximately 30% of the input donor into full-site integration products after 10 min of incubation at 37 degrees C, which is equivalent to isolated retrovirus preintegration complexes for full-site integration activity. DNase I protection analysis demonstrated that wt IN was able to protect the viral DNA ends, mapping approximately 20 bp from the end. We had previously mapped the replication capabilities of several RSV IN mutants (A48P and P115S) which appeared to affect viral DNA integration in vivo. Surprisingly, recombinant RSV A48P IN retained wt IN properties even though the virus carrying this mutation had significantly reduced integrated viral DNA in comparison to wt viral DNA in virus-infected cells. Recombinant RSV P115S IN also displayed all of the properties of wt RSV IN. Upon heating of dimeric P115S IN in solution at 57 degrees C, it became apparent that the mutation in the catalytic core of RSV IN exhibited the same thermolabile properties for 3' OH processing and strand transfer (half-site and full-site integration) activities consistent with the observed temperature-sensitive defect for integration in vivo. The average half-life for inactivation of the three activities were similar, ranging from 1.6 to 1.9 min independent of the IN concentrations in the assay mixtures. Wt IN was stable under the same heat treatment. DNase I protection analysis of several conservative and nonconservative substitutions at W233 (a highly conserved residue of the retrovirus C-terminal domain) suggests that this region is involved in protein-DNA interactions at the viral DNA attachment site. Our data suggest that the use of recombinant RSV IN to investigate efficient full-site integration in vitro with reference to integration in vivo is promising.

Autologous chondrocyte implantation

Rationale for the treatment of cartilage damage in younger patients depends on a thorough understanding of the predisposing factors for the chondrosis and the stage of disease. Implantation with autologous cultured chondrocytes allows for resurfacing of larger defect areas with reproducibly good/excellent results in 90% of patients with isolated lesions of the femoral condyle. Patellar lesions also may be successfully treated (approximately 75% improved) but strict attention must be given to correction of malalignment. Results in patients with tibial and salvage lesions are encouraging; however, these results should be viewed with caution due to the small number of patients with 2-year follow-up. Autologous chondrocyte implantation involves an open technique with the inherent disadvantages of adhesions and a more prolonged recovery. However, these disadvantages must be weighed against the procedure's ability to produce a hyaline-type tissue with greater durability than fibrocartilage repairs produced by traditional marrow-stimulation techniques. We recommended matching the treatment procedure to patient expectations and lesion/demographic characteristics. Based on the available literature. algorithms have been published that recommend autologous chondrocyte implantation be reserved as first-line treatment for high-demand patients with large lesions (>2 cm2) and as revision therapy in patients with lesions of all sizes, regardless of patient demand, who have failed alternative marrow stimulation techniques.

Intra-observer and inter-observer repeatability of anterior eye segment analysis system (EAS-1000) in anterior chamber configuration

BACKGROUND

Anterior chamber configuration can be assessed via optical or ultrasonic techniques. Scheimpflug photography is a non-invasive method measuring the anterior segment. The Anterior Eye Segment analysis system, EAS-1000, utilises the Scheimpflug principle and was found to have good repeatability. Previous repeatability studies, however, have had limitations in their design. The current study investigated the intra-observer and interobserver repeatability of the EAS-1000.

METHODS

Twenty-five healthy young subjects were recruited. The anterior chamber angles in different quadrants were measured by two examiners for interobserver analysis. The first examiner repeated the measurement at another session for intra-observer analysis. The 95% limits of agreement and intra-class correlation coefficient (ICC) were calculated. The anterior chamber depth was also measured and compared with ultrasound biometry.

RESULTS

The anterior chamber angle assessment demonstrated good intra-observer (ICC ranging from 0.77 to 0.90 for different quadrants) and interobserver (ICC ranging from 0.68 to 0.81 for different quadrants) repeatability. The 95% intra-observer limits of agreement were within +/-5 degrees. The 95% interobserver limits of agreement were within +/-6 degrees. There was no significant difference between male and female subjects or among angles at different quadrants. The anterior chamber depth was found to be repeatable (ICC > 0.90) with 95% limits of agreement +/-0.1 mm. The anterior chamber depth was shallower than that obtained from ultrasound biometry.

CONCLUSIONS

The EAS-100 is a non-invasive instrument which is repeatable for measuring the anterior chamber angle and depth. It provides quick results and is good for screening purposes. There is an under-estimation of anterior chamber depth, as previously reported.

Avian retrovirus DNA internal attachment site requirements for full-site integration in vitro

Concerted integration of retrovirus DNA termini into the host chromosome in vivo requires specific interactions between the cis-acting attachment (att) sites at the viral termini and the viral integrase (IN) in trans. In this study, reconstruction experiments with purified avian myeloblastosis virus (AMV) IN and retrovirus-like donor substrates containing wild-type and mutant termini were performed to map the internal att DNA sequence requirements for concerted integration, here termed full-site integration. The avian retrovirus mutations were modeled after internal att site mutations studied at the in vivo level with human immunodeficiency virus type 1 (HIV-1) and murine leukemia virus (MLV). Systematic overlapping 4-bp deletions starting at nucleotide positions 7, 8, and 9 in the U3 terminus had a decreasing detrimental gradient effect on full-site integration, while more internal 4-bp deletions had little or no effect. This decreasing detrimental gradient effect was measured by the ability of mutant U3 ends to interact with wild-type U3 ends for full-site integration in trans. Modification of the highly conserved C at position 7 on the catalytic strand to either A or T resulted in the same severe decrease in full-site integration as the 4-bp deletion starting at this position. These studies suggest that nucleotide position 7 is crucial for interactions near the active site of IN for integration activity and for communication in trans between ends bound by IN for full-site integration. The ability of AMV IN to interact with internal att sequences to mediate full-site integration in vitro is similar to the internal att site requirements observed with MLV and HIV-1 in vivo and with their preintegration complexes in vitro.

12-O-tetradecanoylphorbol-13-acetate (TPA)-induced c-Jun N-terminal kinase (JNK) phosphatase renders immortalized or transformed epithelial cells refractory to TPA-inducible JNK activity

c-Jun N-terminal kinase (JNK) regulates gene expression in response to various extracellular stimuli. JNK can be activated by the tumor promoting agent, 12-O-tetradecanoylphorbol-13-acetate (TPA) in normal human oral keratinocytes but not in human keratinocytes that have been immortalized (HOK-16B and HaCaT) or transformed (HOK-16B-Bap-T) nor in a cervical carcinoma cell line (HeLa). The refractory JNK activation response to TPA is not due a defect in the JNK pathway, because JNK can be activated by other stimuli, e.g. UV irradiation and an alkylating agent N-methyl-N'-nitrosoguanidine in these immortalized or transformed cells. More importantly, the refractory JNK and JNKK activation response to TPA can be restored by treatment of the cells with a combination of TPA and a protein-tyrosine phosphatase inhibitor, sodium orthovanadate. Furthermore, pretreatment of cells with TPA partially inhibited UV- or N-methyl-N'-nitrosoguanidine-induced JNK activity. These results suggest that a TPA-inducible, orthovanadate-sensitive protein-tyrosine phosphatase may specifically down-regulate JNK signaling pathway in these immortalized/transformed epithelial cells. In contrast, ERK and p38/Mpk2 are not regulated by this TPA-induced phosphatase. This putative protein-tyrosine phosphatase appears to be JNK pathway-specific.

ATF-2 has intrinsic histone acetyltransferase activity which is modulated by phosphorylation

Transcription factors carry functional domains, which are often physically distinct, for sequence-specific DNA binding, transcriptional activation and regulatory functions. The transcription factor ATF-2 is a DNA-binding protein that binds to cyclic AMP-response elements (CREs), forms a homodimer or heterodimer with c-Jun, and stimulates CRE-dependent transcription. Here we report that ATF-2 is a histone acetyltransferase (HAT), which specifically acetylates histones H2B and H4 in vitro. Motif A, which is located in the HAT domain, is responsible for the stimulation of CRE-dependent transcription; moreover, in response to ultraviolet irradiation, phosphorylation of ATF-2 is accompanied by enhanced HAT activity of ATF-2 and CRE-dependent transcription. These results indicate that phosphorylation of ATF-2 controls its intrinsic HAT activity and its action on CRE-dependent transcription. ATF-2 may represent a new class of sequence-specific factors, which are able to activate transcription by direct effects on chromatin components.

The E7 oncoprotein of human papillomavirus type 16 interacts with F-actin in vitro and in vivo

We report here that E7 oncoprotein of human papillomavirus type 16 (HPV-16) forms a complex in vivo and in vitro with actin, one of the components of the cellular cytoskeleton. The in vivo interaction was detected by immunofluorescent staining and confocal microscopic examination of normal human oral keratinocytes (NHOK) and CV-1 cells after transient expression of E7 employing the vaccinia virus-T7 RNA polymerase system and by coimmunoprecipitation from an immortalized, nontumorigenic cell line obtained after transfecting NHOK with the cloned HPV-16 DNA genome. The in vitro interaction was detected by cosedimentation of bacterially expressed E7 phosphorylated with rabbit reticulocyte lysate or purified casein kinase II (CKII) prior to incubation with F-actin. This interaction was inhibited if E7 phosphorylation by the rabbit reticulocyte lysate was prevented with heparin, a CKII inhibitor, or if the amino acids Ser-31 and Ser-32 in E7, which are phosphorylated by CKII, were replaced with amino acids that cannot be phosphorylated. Interestingly, a decrease in the amount of polymerized actin occurred in cells expressing E7.

Residual bladder dysfunction 2 to 10 years after acute transverse myelitis

OBJECTIVE

Acute transverse myelitis (ATM) is a relatively rare condition in children. The recovery rate is reported to be generally complete. In the current study, the long-term urological outcome of children with ATM was assessed.

METHODOLOGY

The medical records of children with ATM admitted to Queen Mary Hospital, Hong Kong, over the last 15 years, were reviewed.

RESULTS

The median age of the five children with ATM at the time of onset was 6 years (range = 2-12 years). The median length of follow up was 5 years (2-10 years). Four children recovered completely from paraparesis; two had no urinary symptoms with normal micturition. However, video-urodynamic studies 3 years after the acute onset revealed that four out of the five children, including one without any urinary symptom, suffered from residual bladder dysfunction - two from contractile neurogenic bladder and two from intermediate type of neurogenic bladder.

CONCLUSION

Residual bladder dysfunction is common in children suffering from ATM despite improvement of paraparesis and apparent lack of urological symptoms. Long-term follow up of urological function in these patients is recommended.

Retrovirus DNA termini bound by integrase communicate in trans for full-site integration in vitro

Integration of linear retrovirus DNA involves the concerted insertion of the viral termini (full-site integration) into the host chromosome. We investigated the interactions that occur between long terminal repeat (LTR) termini bound by avian retrovirus integrase (IN) for full-site integration in vitro. Wild-type (wt) or mutant LTR donors that possess gain-of-function ("G") or loss-of-function ("L") for full-site integration activity were used. G LTR termini are characterized as having significantly higher strand transfer activity than the wt and the L LTR termini. L LTR mutations are classified as partially or extremely defective for strand transfer activity. The L mutations were further classified by their ability to either permit or block the assembly of G or wt LTR termini into nucleoprotein complexes capable of full-site strand transfer. We demonstrated that avian myeloblastosis virus IN bound to G LTR termini increased the incorporation of partially defective L LTR termini into nucleoprotein complexes that were capable of full-site integration. The observed full-site integration activity of these assembled nucleoprotein complexes appeared to be influenced by each individual IN-LTR complex in trans. In contrast, extremely defective L LTR termini exhibited the ability to effectively block the assembly of wt LTR termini into nucleoprotein complexes capable of full-site strand transfer. Data from nonspecific DNA competition experiments suggested that IN had an apparent higher affinity for G LTR donor termini than for partially defective L LTR donor termini as measured by full-site integration activity. However, assembled nucleoprotein complexes containing either two G or two L LTR donors were stable, having a similar half-life of approximately 2 h on ice. The results suggest that LTR termini bound by IN exhibit an allosteric effect to modulate full-site integration in vitro. Similar regulatory controls also appear to exist in vivo between the wt U3 and wt U5 LTR termini in retroviruses as well as purified retrovirus preintegration complexes that promoted full-site integration in vitro.

Cutaneous rat wounds express c49a, a novel gene with homology to the human melanoma differentiation associated gene, mda-7

We have used DD-PCR (differential display-polymerase chain reaction) to identify new genes that are over- or underexpressed during wound repair. DD-PCR performed on excisional wounds identified the expression of rat c49a. Cloning and sequence analysis of the rat c49a gene revealed high homology to a novel human melanoma differentiation associated gene, mda-7. The human mda-7gene isolated from melanoma cell lines, has been linked with human melanoma differentiation, and growth suppression. Moreover, transfection of human mda-7 constructs into human tumor cells suppresses the growth and colony formation of tumor cells from diverse origins. To confirm and relatively quantitate expression of rat c49a gene during repair, specific primer, reduced cycle RT-PCR (reverse transcription-PCR) was performed. RT-PCR showed an approximately 9 to 12-fold elevation of rat c49a mRNA at 12 h to 5 days above nonwounded controls that gradually decreased to approximately 1.5 to 3-fold by day 14. Cloning and sequence analysis of the entire 1200 base pair c49a gene product showed 78% nucleotide homology to human mda-7. Immunohistochemistry studies localized rat C49A expression primarily to fibroblast-like cells at the wound edge and base. The marked up-regulation of rat c49a transcripts during the inflammatory and early granulation tissue phases of wound repair where cellular processes such as re-epithelialization, angiogenesis, and fibroplasia predominate--suggest that c49a is associated with proliferation of fibroblasts in wound healing.

Recruitment of the retinoblastoma protein to c-Jun enhances transcription activity mediated through the AP-1 binding site

The retinoblastoma susceptibility gene product (RB) is a transcriptional modulator. One of the targets for this modulator effect is the AP-1 binding site within the c-jun and collagenase promoters. The physical interactions between RB and c-Jun were demonstrated by co-immunoprecipitation of these two proteins using anti-c-Jun or anti-RB antisera, glutathione S-transferase affinity matrix binding assays in vitro, and electrophoretic mobility shift assays. The C-terminal site of the leucine zipper of c-Jun mediated the interaction with RB. Although the B-pocket domain of RB alone bound to c-Jun, a second c-Jun binding site in the RB was also suggested. Mammalian two-hybrid-based assay provided corroborative evidence that transactivation of gene expression by RB required the C-terminal region of c-Jun. We conclude that RB enhances transcription activity mediated through the AP-1 binding site. Adenovirus E1A or human papillomavirus E7 inhibits RB-mediated transcription activity. These data reveal that the interactions between these two distinct classes of oncoproteins RB and c-Jun may be involved in controlling cell growth and differentiation mediated by transcriptional regulation.

Distinct roles of the co-activators p300 and CBP in retinoic-acid-induced F9-cell differentiation

The related proteins p300 and CBP (cAMP-response-element-binding protein (CREB)-binding protein)) are transcriptional co-activators that act with other factors to regulate gene expression and play roles in many cell-differentiation and signal transduction pathways. Both proteins have intrinsic histone-acetyltransferase activity and may act directly on chromatin, of which histone is a component, to facilitate transcription. They are also involved in growth control pathways, as shown by their interaction with the tumour suppressor p53 and the viral oncogenes E1A and SV40 T antigen. Here we report functional differences of p300 and CBP in vivo. We examined their roles during retinoic-acid-induced differentiation, cell-cycle exit and programmed cell death (apoptosis) of embryonal carcinoma F9 cells, using hammerhead ribozymes capable of cleaving either p300 or CBP messenger RNAs. F9 cells expressing a p300-specific ribozyme became resistant to retinoic-acid-induced differentiation, whereas cells expressing a CBP-specific ribozyme were unaffected. Similarly, retinoic-acid-induced transcriptional upregulation of the cell-cycle inhibitor p21Cip1 required normal levels of p300, but not CBP, whereas the reverse was true for p27Kip1. In contrast, both ribozymes blocked retinoic-acid-induced apoptosis, indicating that both co-activators are required for this process. Thus, despite their similarities, p300 and CBP have distinct functions during retinoic-acid-induced differentiation of F9 cells.

p300 and ATF-2 are components of the DRF complex, which regulates retinoic acid- and E1A-mediated transcription of the c-jun gene in F9 cells

Transcriptional activation of the c-jun gene is a critical event in the differentiation of F9 cells. In our previous studies we characterized an element [differentiation response element (DRE)] in the c-jun promoter that is both necessary and sufficient to confer the capacity for differentiation-dependent up-regulation. This element binds the differentiation regulatory factor (DRF) complex, of which one component is the adenovirus E1A-associated protein p300. We have now identified activation transcription factor-2 (ATF-2) as a DNA-binding subunit of the DRF complex. p300 and ATF-2 interact with each other in vivo and in vitro. The bromodomain and the C/H2 domain of p300 mediate the binding to ATF-2, which in turn requires a proline-rich region between amino acids 112 and 350 for its interaction with p300. The phosphorylation of the serine residue at position 121 of ATF-2 appears to be induced by protein kinase C alpha (PKC alpha) after treatment of cells with retinoic acid (RA) or induction with E1A. In cotransfection assays, wild-type ATF-2 enhanced the transcription of an E2/tk-luciferase construct, in conjunction with p300-E2. However, a mutant form of ATF-2 with a mutation at position 121 (pCMVATF-2(Ser121-Ala)) did not. These results suggest that ATF-2 and p300 cooperate in the control of transcription by forming a protein complex that is responsive to differentiation-inducing signals, such as RA or E1A, and moreover, that the phosphorylation of ATF-2 by PKC alpha is probably a signaling event in the pathway that leads to the transactivation of the c-jun gene in F9 cells.

A retinoblastoma susceptibility gene product, RB, targeting protease is regulated through the cell cycle

Degradation of cyclin B and cyclin-dependent kinase inhibitor, p27, at a specific time has been shown to play a critical role in regulating the cell cycle. SPase, a nuclear and cytosol protease with cathepsin B- and L-like proteolytic activity, has been identified in several cell lines. This proteolytic enzyme selectively degraded nuclear proteins such as retinoblastoma susceptibility gene product, RB, and transcription factor, SP-1. High levels of SPase activity were detected at the G1/S, moderate levels at the G1 and S phases, and undetectable activity at the M phase of synchronized CV-1 cells, suggesting that SPase activity is regulated through the cell cycle. Degradation of RB correlated with SPase activity throughout the cell cycle, suggesting that SPase regulates RB, which has a functional role in regulating cell cycle. These results demonstrated that SPase plays an integral role in regulating the nuclear regulator, RB, in controlling cell cycle progression.

Avian retrovirus U3 and U5 DNA inverted repeats. Role Of nonsymmetrical nucleotides in promoting full-site integration by purified virion and bacterial recombinant integrases

The U3 and U5 termini of linear retrovirus DNA contain imperfect inverted repeats that are necessary for the concerted insertion of the termini into the host chromosome by viral integrase. Avian myeloblastosis virus integrase can efficiently insert the termini of retrovirus-like DNA donor substrates (480 base pairs) by a concerted mechanism (full-site reaction) into circular target DNA in vitro. The specific activities of virion-derived avian myeloblastosis virus integrase and bacterial recombinant Rous sarcoma virus (Prague A strain) integrase (approximately 50 nM or less) appear similar upon catalyzing the full-site reaction with 3'-OH recessed wild type or mutant donor substrates. We examined the role of the three nonsymmetrical nucleotides located at the 5th, 8th, and 12th positions in the U3 and U5 15-base pair inverted repeats for their ability to modify the full-site and simultaneously, the half-site strand transfer reactions. Our data suggest that the nucleotide at the 5th position appears to be responsible for the 3-5-fold preference for wild type U3 ends over wild type U5 ends by integrase for concerted integration. Additional mutations at the 5th or 6th position, or both, of U3 or U5 termini significantly increased (approximately 3 fold) the full-site reactions of mutant donors over wild type donors.