Novel Microbial Palladium Nanoparticles with a High Photothermal Effect for Antibacterial Applications.

Novel biocompatible palladium nanoparticles (Pd-NPs) have been prepared by microorganisms via Bacillus megaterium Y-4. It was demonstrated that ultrasonication treatment of biologically reduced Pd-NPs impart a much higher absorption in NIR regions and a better photothermal conversion efficiency to the material. The as-prepared material showed excellent biocompatibility and antibacterial activity under NIR irradiation. In less than 10 min, the disinfection efficiency for a low dosage of Pd-NPs (20 mg/L) was 99.99% toward both Staphylococcus aureus and Escherichia coli. The exclusive and even dispersed microbial Pd-NPs display a high efficiency of photothermal conversion under the irradiation of NIR, which endows them with excellent antibacterial activity in a low dosage.

On the fossil and non-fossil fuel sources of carbonaceous aerosol with radiocarbon and AMS-PMF methods during winter hazy days in a rural area of North China plain.

Regional transport is a key source of carbonaceous aerosol in many Chinese megacities including Beijing. The sources of carbonaceous aerosol in urban areas have been studied extensively but are poorly known in upwind rural areas. This work aims to quantify the contributions of fossil and non-fossil fuel emissions to carbonaceous aerosols at a rural site in North China Plain in winter 2016. We integrated online high resolution-time of flight-aerosol mass spectrometer (HR-TOF-AMS) observations and radiocarbon (14C) measurements of fine particles with Positive Matrix Factorization (PMF) analysis as well as Extended Gelencsér (EG) method. We found that fine particle concentration is much higher at the rural site than in Beijing during the campaign (Dec 7, 2016 to Jan 8, 2017). PMF analysis of the AMS data showed that coal-combustion related organic aerosol (CCOA + Oxidized CCOA) and more oxidized oxygenated organic aerosol (MO-OOA) contributed 48% and 30% of organic matter to non-refractory PM1 (NR-PM1) mass. About 2/3 of the OC and EC were from fossil-fuel combustion. The EG method, combining AMS-PMF and 14C data, showed that primary and secondary OC from fossil fuel contribute 35% and 22% to total carbon (TC), coal combustion emission dominates the fossil fuel sources, and biomass burning accounted for 21% of carbonaceous aerosol. In summary, our results confirm that fossil fuel combustion was the dominant source of carbonaceous aerosol during heavy pollution events in the rural areas. Significant emissions of solid fuel carbonaceous aerosols at rural areas can affect air quality in downwind cities such as Beijing and Tianjin, highlighting the benefits of energy transition from solid fuels to cleaner energy in rural areas.

Case report of squamous cell cancer arising in perineal epidermal inclusion cyst, presenting as rapidly enlarging and cavitating lesion.

INTRODUCTION: Cutaneous squamous cell cancer (cSCC) is a common condition, with straight forward and well-known heuristics regarding diagnosis, treatment, and surveillance. cSCC arising in an epidermal inclusion cyst is rare, but not unheard of. In contrast, the authors' are unaware of any prior reports of cSCC arising in an epidermal inclusion cyst within an atypical cavernous and cavitating lesion in the perineum. PRESENTATION OF CASE: A 48-year-old male presented with a cavitating and rapidly growing cutaneous perineal lesion. Preliminary diagnostic procedures (biopsy) showed benign pathology and imaging showed no involvement of perineal organs such as prostate or rectum. Discordance between initial diagnostics and clinical features prompted multi-specialty consultation, including dermatological pathology. Repeat biopsy yielded in situ, possibly invasive squamous cell cancer, arising in the background of an epidermal inclusion cyst. Wide excision with advancement flap reconstruction was employed, with temporary diverting colostomy to avoid perineal sepsis. DISCUSSION: Location and appearance of this lesion provided a diagnostic and treatment challenge requiring multi-specialty involvement for diagnosis and successful treatment. Specialists from urology, general surgery, dermatology, general and dermatological pathology, plastic and reconstructive surgery, colorectal surgery and medical and radiation oncology were involved in diagnosis, treatment plan and execution. None of the specialists involved had seen this singular presentation before, and this created an ownership and management challenge. CONCLUSION: The cavitating, atypical appearance of lesion complicated diagnosis. Location required pre-treatment coordination and deliberation between dermatology, urology, general surgery, and plastic surgery. Malignant degeneration of inclusion cysts, although rare, has to be kept in mind, especially when presenting with rapid growth, and persistence in ruling out malignant diagnosis is fundamental.

Podoplanin is a useful marker for identifying mesothelioma in malignant effusions.

The diagnosis of malignant mesothelioma in serosal effusions continues to be a major challenge because some of its cytomorphological features closely resemble adenocarcinomas. Immunohistochemistry is a valuable tool in the differentiation of epithelioid mesothelioma from metastatic adenocarcinomas. However, no single antibody has demonstrated absolute sensitivity or specificity. In this study, we evaluated the value of immunostaining pattern for podoplanin to differentiate mesothelioma from adenocarcinomas of various origins.Cell blocks from previously collected paraffin-embedded cell blocks of 86 effusions (18 mesothelioma, 35 reactive mesothelium, 9 breast adenocarcinoma, 14 ovarian adenocarcinoma, and 10 lung adenocarcinoma) were retrieved from the file of the Department of Pathology at University of Michigan and Lund University in Sweden and were used for the study. Slides prepared from the cell blocks were stained for podoplanin. The percentage of immunostained cells was recorded as follows: 1+ (5-25%), 2+ (26-50%), and 3+ (>50%). A stain result involving <5% of cells was considered negative. The intensity of positive results was evaluated as strong, moderate, or weak.Podoplanin is expressed in 94% of malignant mesothelioma cases (17/18), 97% (30/31) of cases of reactive mesothelial, 0% of lung adenocarcinoma cases (0/9), 0% of breast adenocarcinoma (0/9), and 7% of ovarian adenocarcinoma (1/14). All positive cases of malignant mesothelioma and reactive mesothelium showed strong membranous reactivity to podoplanin. The one positive case of ovarian adenocarcinoma showed a weak membranous podoplanin immunostaining.On the basis of our results and published data, we believe that membranous podoplanin immunoreactivity, in conjunction with calretinin, would be more specific than CK5/6 and WT-1 in differentiating epithelioid malignant mesothelioma from adenocarcinoma of the lung, breast, and ovary.

Computer-assisted image analysis of amyloid deposits in abdominal fat pad aspiration biopsies.

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.

Fine-needle aspiration biopsy of metastatic malignant melanoma resembling a malignant peripheral nerve sheath tumor.

We report a case of metastatic malignant melanoma resembling a malignant peripheral sheath tumor, which posed a significant diagnostic challenge. The patient is a 76-year-old male, who presented in the emergency room with bilateral chest pain exacerbated by inspiration. The pain was present for 3 week and was not exacerbated by physical exercise. The diagnostic workup revealed bilateral parenchymal pulmonary infiltrates. The CT-scan guided fine-needle aspiration and the core biopsies of the largest pulmonary lesion revealed high-grade spindle cell neoplasm with individual cell apoptosis and necrosis. The immunohistochemical profile on the cell block showed that the cells are positive for Vimentin. The S-100 stain showed only focal positivity. The immunohistochemical stains for HMB45, Melan A, pancytokeratin, and smooth muscle actin were negative. Five years ago the patient was diagnosed with melanoma on the back with Clark level of IV. The melanoma was excised with clear margins and sentinel lymph nodes were negative. Careful examination of patient's previous slides revealed an area of spindle cell melanoma adjacent to a nodular type melanoma. Based on the patient's previous history, current clinico-pathologic presentation and immunohistochemical profile, the diagnosis of metastatic malignant melanoma resembling peripheral nerve sheath tumor was favored over the diagnosis of metastatic malignant spindle cell neoplasm of unknown primary site, which by itself is very rare clinical scenario.

Restoring satisfactory status in ThinPrep Pap test specimens with too few squamous cells and containing microscopic red blood cells.

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.

Utility of WT-1, p63, MOC31, mesothelin, and cytokeratin (K903 and CK5/6) immunostains in differentiating adenocarcinoma, squamous cell carcinoma, and malignant mesothelioma in effusions.

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.

Cellular adequacy for thyroid aspirates prepared by ThinPrep: how many cells are needed?

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%.

Diagnosis of foregut and tailgut cysts by endosonographically guided fine-needle aspiration.

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.

The binding of thyroid transcription factor-1 and hepatocyte paraffin 1 to mitochondrial proteins in hepatocytes: a molecular and immunoelectron microscopic study.

We studied the antibodies hepatocyte paraffin 1 (Hep Par 1) and thyroid transcription factor-1 (TTF-1; clone 8G7G3/1) in normal human liver tissue with immunoelectron microscopy using renal tubules as control samples. TTF-1 (8G7G3/1) and Hep Par 1 bound exclusively to the mitochondria of hepatocytes but not to those of the renal tubular epithelium. Both antibodies labeled mitochondria in a similar pattern and density. These findings confirm that the binding site of Hep Par 1 in hepatocytes is mitochondrial. The specific binding of TTF-1 (8G7G3/1) in hepatocyte mitochondria suggests its potential usefulness for identifying hepatocellular carcinoma. Western blot analysis with cellular proteins extracted from normal human liver and thyroid tissue demonstrated that Hep Par 1 and TTF-1 (8G7G3/1) bound to a protein band of approximately 150 kd in liver cells, with TTF-1 (8G7G3/1) showing less affinity. It is likely that different epitopes to Hep Par 1 and TTF-1 (8G7G3/1) share the same protein molecule in hepatocyte mitochondria.

Diagnostic value of nipple cytology: study of 466 cases.

BACKGROUND: Nipple discharge/scraping cytology is a simple, noninvasive method that complements patient assessment. Despite low reported sensitivities for detecting malignancy, the authors predicted that this method would provide important diagnostic information when applied to patients with nonphysiologic nipple discharge or eczematous nipple lesion. METHODS: From 1995-2002, 466 case specimens from 395 patients were evaluated by nipple discharge or scraping cytology. Of the 98 patients with abnormal cytologic findings, histologic follow-up was available for 45 cases (39 patients). After review, each case was categorized as negative or positive for malignancy. Cytologic findings were compared with the findings of subsequent biopsy or excision of the affected duct or nipple lesion. RESULTS: Of the 13 cases of in situ or invasive carcinoma diagnosed by histology, 11 had positive cytology (sensitivity, 85%). Two malignant cases were not represented by preceding cytology and one case with positive cytology failed to demonstrate malignancy after a subsequent biopsy was performed (specificity, 97%). Clinically, all but one case of malignancy was associated with a serosanguinous discharge or eczematous nipple lesion. The cytology of all malignant cases showed dyshesive epithelial cell groups and single cells with prominent nucleoli in a bloody background. The positive predictive value for cytology was 92% and the negative predictive value was 94%. CONCLUSIONS: Cytologic examination of nipple discharge and nipple lesion scrapings is highly specific and sensitive in the detection of carcinoma when applied to patients with unilateral serosanguinous nipple discharge or an eczematous nipple lesion.