ABSTRACT Postembedding immunoelectron microscopy can be used for the detection of antigenic sites... more ABSTRACT Postembedding immunoelectron microscopy can be used for the detection of antigenic sites in ultrathin sections. The protein A-gold technique, when used in conjunction with tissue dehydration at low temperature followed by embedding in a hydrophilic resin, can provide a satisfactory means for assessing the ultrastructural localization of diagnostically relevant antigens. In this brief article, we will demonstrate the usefulness of this technique to demonstrate the subcellular localization of the binding sites for the melanoma-associated antibodies HMB-45 and MART-1. (The J Histotechnol 26:263, 2003)
A total of 838 staphylococcal isolates representing 19 different species were obtained from cattl... more A total of 838 staphylococcal isolates representing 19 different species were obtained from cattle, cats, dogs, ducks, guinea pigs, horses, mink, pigeons, pigs, rabbits, and turkeys. From these 228 (27.2%) isolates were shown to be resistant to tetracycline and to carry one or two of the tetracycline resistance (tet) genes tet (K), tet (L), tet (M), or tet (O) with seven different distribution patterns. Additional resistances to one or more antibiotics were observed in 153 (67.1%) of the tetracycline resistant isolates. The tet (M) gene was found in 94.3% of the resistant S. intermedius isolates while the tet (K) gene predominated in most of the other staphylococcal species irrespective of the host animal. The tet (K) and tet (L) genes were located on plasmids while the tet (M) and tet (O) genes appeared to be associated with the chromosome.
Clinical and diagnostic laboratory immunology, 1997
The Mycobacterium tuberculosis H37Rv efpA gene encodes a putative efflux protein, EfpA, of 55,670... more The Mycobacterium tuberculosis H37Rv efpA gene encodes a putative efflux protein, EfpA, of 55,670 Da. The deduced EfpA protein was similar in secondary structure to Pur8, MmrA, TcmA, LfrA, EmrB, and other members of the QacA transporter family (QacA TF) which mediate antibiotic and chemical resistance in bacteria and yeast. The predicted EfpA sequence possessed all transporter motifs characteristic of the QacA TF, including those associated with proton-antiport function and the motif considered to be specific to exporters. The 1,590-bp efpA open reading frame was G+C rich (65%), whereas the 40-bp region immediately upstream had an A+T bias (35% G+C). Reverse transcriptase-PCR assays indicated that efpA was expressed in vitro and in situ. Putative promoter sequences were partially overlapped by the A+T-rich region and by a region capable of forming alternative secondary structures indicative of transcriptional regulation in analogous systems. PCR single-stranded conformational polymo...
Between August 1989 and January 1990, 16 patients on an alcoholism rehabilitation ward (ARW) deve... more Between August 1989 and January 1990, 16 patients on an alcoholism rehabilitation ward (ARW) developed positive sputum cultures for Mycobacterium fortuitum. During a 2-wk surveillance period, six of 43 ARW patients but none of 20 staff members had positive sputum cultures. In addition, none of 54 patients and staff on an adjacent ward sharing the same ice machine and water supply had positive cultures, and none of 92 acid-fast bacilli cultures performed on all sputum specimens from all other inpatient sources during the same 2-wk period were positive. The only exposure factor common to all cases was the use of one or both of the ward showers. Compared with 36 ARW control patients, cases were more likely to report clinical criteria for chronic bronchitis (odds ratio, 6.6; 95% confidence interval, 1.5 to 28.6; p = 0.02). Using phenotype analysis, plasmid profiles, and pulsed-field gel electrophoresis of large genomic DNA restriction enzyme fragments, the 16 case isolates were found to be identical. This strain of M. fortuitum was also cultured from a tap connected to the water line supplying the ARW showers, but not from the showers themselves. No further cases were identified after the showers were disconnected and decontaminated. To our knowledge, this is the first clinical use of pulsed-field gel electrophoresis for genetic comparison of mycobacterial strains. It demonstrates the important potential of this technique for studying the epidemiology of mycobacterial infections. Showers should be considered a possible source of nosocomial respiratory tract colonization with M. fortuitum.
ABSTRACT MoO3-Bi2SiO5/SiO2 catalysts with a Mo/Bi molar ratio of 5, prepared by a two-step hydrot... more ABSTRACT MoO3-Bi2SiO5/SiO2 catalysts with a Mo/Bi molar ratio of 5, prepared by a two-step hydrothermal and simple impregnation method, were investigated for the epoxidation of propylene by O2 and characterized by XRD, N2 absorption–desorption isotherms, thermogravimetric analysis (TGA), temperature-programmed reduction, NH3 temperature-programmed desorption (TPD), and IR, Raman, and X-ray photoelectron spectroscopy (XPS). On MoO3-Bi2SiO5/SiO2 with Mo/Bi=5 calcined at 723 K, a propylene conversion of 21.99 % and a propylene oxide selectivity of 55.14 % were obtained at 0.15 MPa, 673 K, and flow rates of C3H6/O2/N2=1/4/20 cm3 min−1. XRD, IR spectroscopy, and XPS results show that Bi2SiO5 and MoO3 are crystalline nanoparticles. NH3-TPD results indicate that the surface acid sites are necessary for the high catalytic activity. The results of TGA and N2 absorption–desorption isotherms reveal that a reasonable calcination temperature is 723 K. The reaction mechanism of propylene epoxidation on MoO3-Bi2SiO5/SiO2 catalysis is hypothesized to involve an allylic radical generated at the molybdenum oxide species and the activation of O2 at the bismuth oxide cations.
A dimolybdenum derivative of decamethylpentasilacycloheptyne (1) was synthesized by direct reacti... more A dimolybdenum derivative of decamethylpentasilacycloheptyne (1) was synthesized by direct reaction of the heptyne with Mo2(CO)4(η5-C5H5)2. 1 crystallized in the space group P1, a=9.386(2), b=9.866(3), c=20.178(4) Å, α=92.17(2), β=97.17(2), γ=115.71(2)°. The acetylenic bond is lengthened from 1.213 Å in the free ligand to 1.359(4) Å and all the Si–Si bond lengths in 1 are significantly lengthened upon complexation. This is due to relaxation of the ring strain as evidenced by the Si–C–C bond angles in 1 of 132.7 and 140.9° compared to 159.2 and 162.6° in the uncomplexed ring. 29Si-NMR data exhibit significant downfield chemical shifts upon complexation for the Si atoms adjacent to the triple bond, with moderate upfield shifts for the other Si atoms. The related cycloheptyne·Mo2(CO)4(η5-C5H5)2 (2) was synthesized by the reaction of cyclohepteno-1,2,3-selenadiazole with Mo2(CO)4(η5-C5H5)2. 2 crystallized in the space group C21/c, a=30.396(10), b=8.9093(3), c=16.156(4) Å, β=115.39(2)°. The acetylenic bond in 2 is 1.345 Å, compared with a calculated value (ab initio 3-21 G*) of 1.190 Å for the free cycloheptyne.
Although it is well established that ThinPrep introduces artifacts to thyroid aspirates, no crite... more Although it is well established that ThinPrep introduces artifacts to thyroid aspirates, no criteria have been established for adequacy of such specimens. This study evaluates the adequate number of cells needed to establish the correct diagnosis based on ThinPrep alone. A total of 218 thyroid aspirates prepared by TP with surgical pathology follow-up were reviewed. The cellularity was calculated as follows: Count the total number of clusters, randomly select 10 clusters and count each, calculate the average number per cluster and multiply by the total number of clusters. A minimum number of 6 clusters with 10 cells each was arbitrary established to assume adequacy for a definitive diagnosis. Cytologic diagnoses were classified as: Nondiagnostic (ND), cystic contents, thyroiditis, nodular hyperplasia (NH), follicular/Hurthle (F/H) cell lesion, F/H cell neoplasm, and carcinoma: qualify. Histologic diagnoses were classified as: Cyst (colloid or otherwise), thyroiditis, NH, F/H adenoma, F/H carcinoma, carcinoma: qualify. Appropriate treatment triage was considered to be clinical for the former 4 cytologic categories and surgical for the latter 3 with ND warranting repeat aspiration. The results were subjected to logistic regressions analysis and contingency tables correlating the number of cells with the cytologic and histologic diagnosis as well as with treatment triage. Cellularity of sample was ranked in 10 deciles according to the number of cells and in 4 quartiles according to the number of clusters. The agreement percentage, for both diagnostic and treatment, was computed for each decile and quartile. 146 (67%) cases had cells and received a diagnosis while 72 (33%) were acellular. Of the 146 cases, 21 contained histiocytes or colloid only. 91/146 (62.3%) were correctly diagnosed and 123/146 (84.3%) would have been correctly triaged for treatment based upon the cytologic diagnosis. Samples with 180 cells or fewer had an agreement rate below 50%. Agreement rate increases to 80% when cellularity is 180-320. Above 320 agreement rate remains high but not uniformly. Total number of clusters did not play an independent role and only the number of cells per cluster had a significant correlation with diagnostic agreement. A 25-cell increase in average cells per cluster increases the odds of agreement between diagnoses by 65%.
To distinguish carcinoma, either adenocarcinoma (ADC) or squamous cell carcinoma (SCC), and malig... more To distinguish carcinoma, either adenocarcinoma (ADC) or squamous cell carcinoma (SCC), and malignant mesothelioma (MM) in effusion can be a diagnostic challenge based on morphology alone. This study evaluates the utility of WT-1, p63, MOC31, mesothelin, and cytokeratin (K903 and CK5/6) immunostains in effusions when ADC and SCC of the lung are in the differential diagnosis with MM. A cohort of 43 effusions consisting of lung ADC (N = 10), SCC (N = 15), and MM (N = 18, mostly (16) pleural based), was subjected to immunostains using the above mentioned antibodies. WT-1 was positive in 100% MM, 0% ADC, and 0% SCC cases while p63 was positive in 0% MM, 30% ADC, and 80% SCC cases. Stain for MOC31 was positive in 100% ADC, 67% SCC, and 35% MM cases. Similarly, mesothelin antibody stained 100% ADC, 60% SCC, and 47% MM cases. Antibodies for K903 and CK5/6 stained 100% SCC cases but fewer ADC cases (40 and 10%, respectively). In conclusion, in this cohort of mostly pleural malignant effusion, MM can be identified with positive staining for WT-1 and negative staining for p63. Conversely, negative staining with WT-1 and positive staining for p63 exclude MM. Used as part of an immunostain panel, cytokeratin markers (CK5/6 and K903) are useful in differentiating SCC from ADC when MM is already excluded, and MOC31 might have limited value in differentiating ADC from MM. A negative stain with MOC31 can exclude lung ADC. Mesothelin, on the other hand, is not useful in the differential diagnosis of ADC, SCC, and MM.
Foregut, hindgut, and tailgut cysts are uncommon developmental anomalies. Clinical and radiologic... more Foregut, hindgut, and tailgut cysts are uncommon developmental anomalies. Clinical and radiological diagnosis can present many challenges, especially in adult patients or when the lesions are in unique locations. Thus, diagnosis has traditionally been provided upon surgical resection. We describe the diagnoses of a gastric foregut cyst and a retrorectal tailgut cyst by endosonographically guided fine-needle aspiration in two adults. The common cytologic features of the specimens are ciliated epithelial cells, proteinaceous material with degenerated debris, histiocytes, and benign appearing epithelium of squamous and/or gastrointestinal type that lack cytologic atypia. The identification of ciliated columnar cells is the key finding. Cytologic diagnosis via endosonographically guided fine-needle aspiration of foregut/hindgut cyst is accurate and less traumatic than surgical biopsies.
Amyloidosis is a heterogeneous group of diseases with a common outcome: deposition of insoluble p... more Amyloidosis is a heterogeneous group of diseases with a common outcome: deposition of insoluble protein in the visceral organs and tissues. Primary amyloidosis is a consequence of different plasma cell disorders, and it is the most common form of amyloidosis in the United States with an estimated 2,000 new cases annually. Other forms of amyloidosis include chronic inflammatory processes, familial type of amyloidosis, and localized forms like Alzheimer's disease.The diagnosis of amyloidosis is based on the clinical picture and demonstration of amyloid deposit in tissues with Congo-red stain. In our article, we describe a simple methodology for image analysis of fat pad biopsies for amyloidosis using a commercially available software Adobe Photoshop CS3(c) Extended Edition. The principle is based on calculation of the mean gray value of each blue and green channel and comparison of their ratios. As a negative control, we have used samples from heart, scar tissue, and skin with their representative control. Fibrous tissue often gives a white:blue to blue:green birefringence, which often is confused with the apple: green birefringence of the amyloid stain; however, we were successful in discriminating these colors using the methodology described in this article. We also analyzed 22 patients with at least 2 years follow-up in our institution. The specificity and the sensitivity of the computer-assisted image analysis were calculated to be 75% and 100%, respectively. These results are in agreement with the published papers (references here); however, caution should be exercised before drawing firm conclusions because of the small sample size presented here.
Treatment of specimens that contain excessive blood can effectively reduce the unsatisfactory rat... more Treatment of specimens that contain excessive blood can effectively reduce the unsatisfactory rate; however, a considerable number of unsatisfactory specimens remain. We evaluated the effectiveness of reprocessing unsatisfactory specimens that had too few squamous cells and contained microscopic red blood cells (TFSQRBC).Out of the 688 unsatisfactory specimens at microscopic screening, 197 (28.63%) were TFSQRBC that were reprocessed by treatment of glacial acetic acid (GAA). Red blood cells were observed clogging the pores in the filter of the ThinPrep device. After reprocessing, 129 (68.48%) yielded a satisfactory diagnosis, which accounted for a reduction of the unsatisfactory rate by 18.25%. In the restored satisfactory specimens, abnormal diagnoses of 1 high-grade squamous intraepithelial lesion (HSIL) (0.78%), 3 atypical glandular cells (AGC) (2.33%), and 13 atypical squamous cells of undetermined significance (ASCUS) (10.08%) were made. The abnormal diagnoses in this group of patients were significantly higher than that in the general population screened.Reprocessing unsatisfactory ThinPrep (TP) specimens of TFSQRBC can reduce the unsatisfactory rate of the TP Pap test significantly and is a cost-effective measure. The initially unsatisfactory specimens are more likely to represent cases with an abnormal diagnosis, which also justifies the effort of reprocessing this group of specimens. Adjustment of the pore size on the ThinPrep filter device may reduce the interference of red blood cells.
ABSTRACT Postembedding immunoelectron microscopy can be used for the detection of antigenic sites... more ABSTRACT Postembedding immunoelectron microscopy can be used for the detection of antigenic sites in ultrathin sections. The protein A-gold technique, when used in conjunction with tissue dehydration at low temperature followed by embedding in a hydrophilic resin, can provide a satisfactory means for assessing the ultrastructural localization of diagnostically relevant antigens. In this brief article, we will demonstrate the usefulness of this technique to demonstrate the subcellular localization of the binding sites for the melanoma-associated antibodies HMB-45 and MART-1. (The J Histotechnol 26:263, 2003)
A total of 838 staphylococcal isolates representing 19 different species were obtained from cattl... more A total of 838 staphylococcal isolates representing 19 different species were obtained from cattle, cats, dogs, ducks, guinea pigs, horses, mink, pigeons, pigs, rabbits, and turkeys. From these 228 (27.2%) isolates were shown to be resistant to tetracycline and to carry one or two of the tetracycline resistance (tet) genes tet (K), tet (L), tet (M), or tet (O) with seven different distribution patterns. Additional resistances to one or more antibiotics were observed in 153 (67.1%) of the tetracycline resistant isolates. The tet (M) gene was found in 94.3% of the resistant S. intermedius isolates while the tet (K) gene predominated in most of the other staphylococcal species irrespective of the host animal. The tet (K) and tet (L) genes were located on plasmids while the tet (M) and tet (O) genes appeared to be associated with the chromosome.
Clinical and diagnostic laboratory immunology, 1997
The Mycobacterium tuberculosis H37Rv efpA gene encodes a putative efflux protein, EfpA, of 55,670... more The Mycobacterium tuberculosis H37Rv efpA gene encodes a putative efflux protein, EfpA, of 55,670 Da. The deduced EfpA protein was similar in secondary structure to Pur8, MmrA, TcmA, LfrA, EmrB, and other members of the QacA transporter family (QacA TF) which mediate antibiotic and chemical resistance in bacteria and yeast. The predicted EfpA sequence possessed all transporter motifs characteristic of the QacA TF, including those associated with proton-antiport function and the motif considered to be specific to exporters. The 1,590-bp efpA open reading frame was G+C rich (65%), whereas the 40-bp region immediately upstream had an A+T bias (35% G+C). Reverse transcriptase-PCR assays indicated that efpA was expressed in vitro and in situ. Putative promoter sequences were partially overlapped by the A+T-rich region and by a region capable of forming alternative secondary structures indicative of transcriptional regulation in analogous systems. PCR single-stranded conformational polymo...
Between August 1989 and January 1990, 16 patients on an alcoholism rehabilitation ward (ARW) deve... more Between August 1989 and January 1990, 16 patients on an alcoholism rehabilitation ward (ARW) developed positive sputum cultures for Mycobacterium fortuitum. During a 2-wk surveillance period, six of 43 ARW patients but none of 20 staff members had positive sputum cultures. In addition, none of 54 patients and staff on an adjacent ward sharing the same ice machine and water supply had positive cultures, and none of 92 acid-fast bacilli cultures performed on all sputum specimens from all other inpatient sources during the same 2-wk period were positive. The only exposure factor common to all cases was the use of one or both of the ward showers. Compared with 36 ARW control patients, cases were more likely to report clinical criteria for chronic bronchitis (odds ratio, 6.6; 95% confidence interval, 1.5 to 28.6; p = 0.02). Using phenotype analysis, plasmid profiles, and pulsed-field gel electrophoresis of large genomic DNA restriction enzyme fragments, the 16 case isolates were found to be identical. This strain of M. fortuitum was also cultured from a tap connected to the water line supplying the ARW showers, but not from the showers themselves. No further cases were identified after the showers were disconnected and decontaminated. To our knowledge, this is the first clinical use of pulsed-field gel electrophoresis for genetic comparison of mycobacterial strains. It demonstrates the important potential of this technique for studying the epidemiology of mycobacterial infections. Showers should be considered a possible source of nosocomial respiratory tract colonization with M. fortuitum.
ABSTRACT MoO3-Bi2SiO5/SiO2 catalysts with a Mo/Bi molar ratio of 5, prepared by a two-step hydrot... more ABSTRACT MoO3-Bi2SiO5/SiO2 catalysts with a Mo/Bi molar ratio of 5, prepared by a two-step hydrothermal and simple impregnation method, were investigated for the epoxidation of propylene by O2 and characterized by XRD, N2 absorption–desorption isotherms, thermogravimetric analysis (TGA), temperature-programmed reduction, NH3 temperature-programmed desorption (TPD), and IR, Raman, and X-ray photoelectron spectroscopy (XPS). On MoO3-Bi2SiO5/SiO2 with Mo/Bi=5 calcined at 723 K, a propylene conversion of 21.99 % and a propylene oxide selectivity of 55.14 % were obtained at 0.15 MPa, 673 K, and flow rates of C3H6/O2/N2=1/4/20 cm3 min−1. XRD, IR spectroscopy, and XPS results show that Bi2SiO5 and MoO3 are crystalline nanoparticles. NH3-TPD results indicate that the surface acid sites are necessary for the high catalytic activity. The results of TGA and N2 absorption–desorption isotherms reveal that a reasonable calcination temperature is 723 K. The reaction mechanism of propylene epoxidation on MoO3-Bi2SiO5/SiO2 catalysis is hypothesized to involve an allylic radical generated at the molybdenum oxide species and the activation of O2 at the bismuth oxide cations.
A dimolybdenum derivative of decamethylpentasilacycloheptyne (1) was synthesized by direct reacti... more A dimolybdenum derivative of decamethylpentasilacycloheptyne (1) was synthesized by direct reaction of the heptyne with Mo2(CO)4(η5-C5H5)2. 1 crystallized in the space group P1, a=9.386(2), b=9.866(3), c=20.178(4) Å, α=92.17(2), β=97.17(2), γ=115.71(2)°. The acetylenic bond is lengthened from 1.213 Å in the free ligand to 1.359(4) Å and all the Si–Si bond lengths in 1 are significantly lengthened upon complexation. This is due to relaxation of the ring strain as evidenced by the Si–C–C bond angles in 1 of 132.7 and 140.9° compared to 159.2 and 162.6° in the uncomplexed ring. 29Si-NMR data exhibit significant downfield chemical shifts upon complexation for the Si atoms adjacent to the triple bond, with moderate upfield shifts for the other Si atoms. The related cycloheptyne·Mo2(CO)4(η5-C5H5)2 (2) was synthesized by the reaction of cyclohepteno-1,2,3-selenadiazole with Mo2(CO)4(η5-C5H5)2. 2 crystallized in the space group C21/c, a=30.396(10), b=8.9093(3), c=16.156(4) Å, β=115.39(2)°. The acetylenic bond in 2 is 1.345 Å, compared with a calculated value (ab initio 3-21 G*) of 1.190 Å for the free cycloheptyne.
Although it is well established that ThinPrep introduces artifacts to thyroid aspirates, no crite... more Although it is well established that ThinPrep introduces artifacts to thyroid aspirates, no criteria have been established for adequacy of such specimens. This study evaluates the adequate number of cells needed to establish the correct diagnosis based on ThinPrep alone. A total of 218 thyroid aspirates prepared by TP with surgical pathology follow-up were reviewed. The cellularity was calculated as follows: Count the total number of clusters, randomly select 10 clusters and count each, calculate the average number per cluster and multiply by the total number of clusters. A minimum number of 6 clusters with 10 cells each was arbitrary established to assume adequacy for a definitive diagnosis. Cytologic diagnoses were classified as: Nondiagnostic (ND), cystic contents, thyroiditis, nodular hyperplasia (NH), follicular/Hurthle (F/H) cell lesion, F/H cell neoplasm, and carcinoma: qualify. Histologic diagnoses were classified as: Cyst (colloid or otherwise), thyroiditis, NH, F/H adenoma, F/H carcinoma, carcinoma: qualify. Appropriate treatment triage was considered to be clinical for the former 4 cytologic categories and surgical for the latter 3 with ND warranting repeat aspiration. The results were subjected to logistic regressions analysis and contingency tables correlating the number of cells with the cytologic and histologic diagnosis as well as with treatment triage. Cellularity of sample was ranked in 10 deciles according to the number of cells and in 4 quartiles according to the number of clusters. The agreement percentage, for both diagnostic and treatment, was computed for each decile and quartile. 146 (67%) cases had cells and received a diagnosis while 72 (33%) were acellular. Of the 146 cases, 21 contained histiocytes or colloid only. 91/146 (62.3%) were correctly diagnosed and 123/146 (84.3%) would have been correctly triaged for treatment based upon the cytologic diagnosis. Samples with 180 cells or fewer had an agreement rate below 50%. Agreement rate increases to 80% when cellularity is 180-320. Above 320 agreement rate remains high but not uniformly. Total number of clusters did not play an independent role and only the number of cells per cluster had a significant correlation with diagnostic agreement. A 25-cell increase in average cells per cluster increases the odds of agreement between diagnoses by 65%.
To distinguish carcinoma, either adenocarcinoma (ADC) or squamous cell carcinoma (SCC), and malig... more To distinguish carcinoma, either adenocarcinoma (ADC) or squamous cell carcinoma (SCC), and malignant mesothelioma (MM) in effusion can be a diagnostic challenge based on morphology alone. This study evaluates the utility of WT-1, p63, MOC31, mesothelin, and cytokeratin (K903 and CK5/6) immunostains in effusions when ADC and SCC of the lung are in the differential diagnosis with MM. A cohort of 43 effusions consisting of lung ADC (N = 10), SCC (N = 15), and MM (N = 18, mostly (16) pleural based), was subjected to immunostains using the above mentioned antibodies. WT-1 was positive in 100% MM, 0% ADC, and 0% SCC cases while p63 was positive in 0% MM, 30% ADC, and 80% SCC cases. Stain for MOC31 was positive in 100% ADC, 67% SCC, and 35% MM cases. Similarly, mesothelin antibody stained 100% ADC, 60% SCC, and 47% MM cases. Antibodies for K903 and CK5/6 stained 100% SCC cases but fewer ADC cases (40 and 10%, respectively). In conclusion, in this cohort of mostly pleural malignant effusion, MM can be identified with positive staining for WT-1 and negative staining for p63. Conversely, negative staining with WT-1 and positive staining for p63 exclude MM. Used as part of an immunostain panel, cytokeratin markers (CK5/6 and K903) are useful in differentiating SCC from ADC when MM is already excluded, and MOC31 might have limited value in differentiating ADC from MM. A negative stain with MOC31 can exclude lung ADC. Mesothelin, on the other hand, is not useful in the differential diagnosis of ADC, SCC, and MM.
Foregut, hindgut, and tailgut cysts are uncommon developmental anomalies. Clinical and radiologic... more Foregut, hindgut, and tailgut cysts are uncommon developmental anomalies. Clinical and radiological diagnosis can present many challenges, especially in adult patients or when the lesions are in unique locations. Thus, diagnosis has traditionally been provided upon surgical resection. We describe the diagnoses of a gastric foregut cyst and a retrorectal tailgut cyst by endosonographically guided fine-needle aspiration in two adults. The common cytologic features of the specimens are ciliated epithelial cells, proteinaceous material with degenerated debris, histiocytes, and benign appearing epithelium of squamous and/or gastrointestinal type that lack cytologic atypia. The identification of ciliated columnar cells is the key finding. Cytologic diagnosis via endosonographically guided fine-needle aspiration of foregut/hindgut cyst is accurate and less traumatic than surgical biopsies.
Amyloidosis is a heterogeneous group of diseases with a common outcome: deposition of insoluble p... more Amyloidosis is a heterogeneous group of diseases with a common outcome: deposition of insoluble protein in the visceral organs and tissues. Primary amyloidosis is a consequence of different plasma cell disorders, and it is the most common form of amyloidosis in the United States with an estimated 2,000 new cases annually. Other forms of amyloidosis include chronic inflammatory processes, familial type of amyloidosis, and localized forms like Alzheimer's disease.The diagnosis of amyloidosis is based on the clinical picture and demonstration of amyloid deposit in tissues with Congo-red stain. In our article, we describe a simple methodology for image analysis of fat pad biopsies for amyloidosis using a commercially available software Adobe Photoshop CS3(c) Extended Edition. The principle is based on calculation of the mean gray value of each blue and green channel and comparison of their ratios. As a negative control, we have used samples from heart, scar tissue, and skin with their representative control. Fibrous tissue often gives a white:blue to blue:green birefringence, which often is confused with the apple: green birefringence of the amyloid stain; however, we were successful in discriminating these colors using the methodology described in this article. We also analyzed 22 patients with at least 2 years follow-up in our institution. The specificity and the sensitivity of the computer-assisted image analysis were calculated to be 75% and 100%, respectively. These results are in agreement with the published papers (references here); however, caution should be exercised before drawing firm conclusions because of the small sample size presented here.
Treatment of specimens that contain excessive blood can effectively reduce the unsatisfactory rat... more Treatment of specimens that contain excessive blood can effectively reduce the unsatisfactory rate; however, a considerable number of unsatisfactory specimens remain. We evaluated the effectiveness of reprocessing unsatisfactory specimens that had too few squamous cells and contained microscopic red blood cells (TFSQRBC).Out of the 688 unsatisfactory specimens at microscopic screening, 197 (28.63%) were TFSQRBC that were reprocessed by treatment of glacial acetic acid (GAA). Red blood cells were observed clogging the pores in the filter of the ThinPrep device. After reprocessing, 129 (68.48%) yielded a satisfactory diagnosis, which accounted for a reduction of the unsatisfactory rate by 18.25%. In the restored satisfactory specimens, abnormal diagnoses of 1 high-grade squamous intraepithelial lesion (HSIL) (0.78%), 3 atypical glandular cells (AGC) (2.33%), and 13 atypical squamous cells of undetermined significance (ASCUS) (10.08%) were made. The abnormal diagnoses in this group of patients were significantly higher than that in the general population screened.Reprocessing unsatisfactory ThinPrep (TP) specimens of TFSQRBC can reduce the unsatisfactory rate of the TP Pap test significantly and is a cost-effective measure. The initially unsatisfactory specimens are more likely to represent cases with an abnormal diagnosis, which also justifies the effort of reprocessing this group of specimens. Adjustment of the pore size on the ThinPrep filter device may reduce the interference of red blood cells.
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Papers by Yijun Pang