Microbiology 2.0-A "behind the scenes" consideration for artificial intelligence applications for interpretive culture plate reading in routine diagnostic laboratories.

Laboratory automation with Artificial Intelligence (AI) features have now emerged into routine diagnostic clinical use to interpret growth on agar plates. Applications are currently limited to urine samples and infection control screens, yet some of the details around the development of algorithms remain entrenched with AI development specialists and are not well understood by laboratorians. The generation of algorithms is not a trivial task and is a highly structured process, with several considerations needed to develop the appropriate data for specific intended uses. Understanding these considerations highlights the limitations of any algorithm created and informs better design practices so that algorithm objectives can be thoroughly tested prior to routine use.

Subpolar North Atlantic western boundary density anomalies and the Meridional Overturning Circulation.

Changes in the Atlantic Meridional Overturning Circulation, which have the potential to drive societally-important climate impacts, have traditionally been linked to the strength of deep water formation in the subpolar North Atlantic. Yet there is neither clear observational evidence nor agreement among models about how changes in deep water formation influence overturning. Here, we use data from a trans-basin mooring array (OSNAP-Overturning in the Subpolar North Atlantic Program) to show that winter convection during 2014-2018 in the interior basin had minimal impact on density changes in the deep western boundary currents in the subpolar basins. Contrary to previous modeling studies, we find no discernable relationship between western boundary changes and subpolar overturning variability over the observational time scales. Our results require a reconsideration of the notion of deep western boundary changes representing overturning characteristics, with implications for constraining the source of overturning variability within and downstream of the subpolar region.

A sea change in our view of overturning in the subpolar North Atlantic.

To provide an observational basis for the Intergovernmental Panel on Climate Change projections of a slowing Atlantic meridional overturning circulation (MOC) in the 21st century, the Overturning in the Subpolar North Atlantic Program (OSNAP) observing system was launched in the summer of 2014. The first 21-month record reveals a highly variable overturning circulation responsible for the majority of the heat and freshwater transport across the OSNAP line. In a departure from the prevailing view that changes in deep water formation in the Labrador Sea dominate MOC variability, these results suggest that the conversion of warm, salty, shallow Atlantic waters into colder, fresher, deep waters that move southward in the Irminger and Iceland basins is largely responsible for overturning and its variability in the subpolar basin.

Incorporating blood-based liquid biopsy information into cancer staging: time for a TNMB system?

Tissue biopsy is the standard diagnostic procedure for cancer. Biopsy may also provide material for genotyping, which can assist in the diagnosis and selection of targeted therapies but may fall short in cases of inadequate sampling, particularly from highly heterogeneous tumors. Traditional tissue biopsy suffers greater limitations in its prognostic capability over the course of disease, most obviously as an invasive procedure with potential complications, but also with respect to probable tumor clonal evolution and metastasis over time from initial biopsy evaluation. Recent work highlights circulating tumor DNA (ctDNA) present in the blood as a supplemental, or perhaps an alternative, source of DNA to identify the clinically relevant cancer mutational landscape. Indeed, this noninvasive approach may facilitate repeated monitoring of disease progression and treatment response, serving as a means to guide targeted therapies based on detected actionable mutations in patients with advanced or metastatic solid tumors. Notably, ctDNA is heralding a revolution in the range of genomic profiling and molecular mechanisms to be utilized in the battle against cancer. This review will discuss the biology of ctDNA, current methods of detection and potential applications of this information in tumor diagnosis, treatment, and disease prognosis. Conventional classification of tumors to describe cancer stage follow the TNM notation system, heavily weighting local tumor extent (T), lymph node invasion (N), and detectable metastasis (M). With recent advancements in genomics and bioinformatics, it is conceivable that routine analysis of ctDNA from liquid biopsy (B) may make cancer diagnosis, treatment, and prognosis more accurate for individual patients. We put forward the futuristic concept of TNMB tumor classification, opening a new horizon for precision medicine with the hope of creating better outcomes for cancer patients.

Dermatofibroma-like granular cell tumor.

BACKGROUND: There have been several reports in the literature of dermatofibromas with granular cells. Here we report a granular cell tumor with the architecture of a dermatofibroma. This is the first report of this histological variant of granular cell tumor. The lesion was a 2.5-cm oval, hyperpigmented plaque present for "years" on the back of a 60-year-old African-American woman. METHODS: The specimen was processed using formalin fixation and paraffin embedding. Tissue sections were stained with hematoxylin and eosin. Immunohistochemical studies were performed with antibodies directed against S-100 protein, neuron-specific enolase, and factor XIIIa. RESULTS: Histopathologic examination revealed granular cells, some of which were spindle shaped, distributed singly and in small groups between collagen bundles resembling a dermatofibroma. Immunohistochemical studies showed the tumor cells to be positive for S-100 and neuron-specific enolase and negative for factor XIIIa. CONCLUSION: The immunohistochemical findings support the diagnosis of a granular cell tumor with a dermatofibroma-like pattern.

Primary localized extranodal hodgkin disease of the transverse colon.

Extranodal Hodgkin disease presenting as a primary localized neoplasm is uncommon, with rare case reports describing primary sites other than lymph nodes. The gastrointestinal tract is the most frequent site of involvement by extranodal Hodgkin disease, typically involving the stomach or small bowel. To date, we have been able to find only one fully documented case of Hodgkin disease of the sigmoid colon confirmed by immunohistochemical studies. We report a case of extranodal Hodgkin disease involving the transverse colon, presenting as inflammatory bowel disease and documented by light microscopic, immunohistochemical, cytogenetic, and molecular studies.

Immunohistologic evaluation of metastatic carcinomas of unknown origin: an algorithmic approach.

Pathologists are now asked frequently to determine the primary site for metastatic carcinomas of unknown origin (MCUO), using adjunctive morphological techniques such as electron microscopy, immunohistology, and other modalities. The authors present an algorithmic immunohistochemical approach to this problem that is based on their experience with over 2,800 routinely-processed epithelial malignancies of various types. These have been studied with antibodies to keratins, vimentin, epithelial membrane antigen, MOC-31, tumor associated-glycoprotein-72 (recognized by monoclonal antibody B72.3), prostate-specific antigen, thyroglobulin, gross cystic disease fluid protein-15, carcinoembryonic antigen, CA-125, CA19-9, placental alkaline phosphatase, S100 protein, and estrogen receptor protein. The algorithm that is structured around these 14 analytes is based on the relative predictive value of each marker, which in turn, determines its place in the sequence of interpretation. The authors' experience with this approach shows 67% accuracy with regard to the ultimately determined site of origin for MCUO, a figure which is similar to that reported by other investigators.

CD31 immunoreactivity in small round cell tumors.

CD31 has been shown to be a sensitive and specific marker for endothelial differentiation among epithelioid and spindled-pleomorphic human neoplasms. However, the role of this marker in the evaluation of small round cell tumors has not been evaluated. Formalin-fixed, paraffin-embedded tissue sections from 276 small round cell tumors, including 85 Ewing's sarcoma/primitive neuroectodermal tumors (ES/PNET), 52 rhabdomyosarcomas, 10 extraabdominal polyphenotypic small cell tumors, six desmoplastic small cell tumors, 11 neuroblastomas, 23 Wilms' tumors, 20 retinoblastomas, 13 esthesioneuroblastomas, and 56 small cell malignant lymphomas were stained with CD31 (JC/70A, 1:40), using a modified avidinbiotin-peroxidase complex technique, after citrate buffer microwave epitope retrieval. Among nonlymphoid small round cell tumors, four of 85 ES/PNET were at least focally reactive. No other lesion in this group was positive. In contrast, the majority of well-differentiated (11 of 17), intermediately differentiated (two of three), and lymphoblastic lymphomas (three of three) were positive. Small cleaved lymphomas (three of 13 follicular, one of 13 diffuse) were less often reactive, whereas small noncleaved lesions were negative. Although reactivity for CD31 in ES/PNET is uncommon, the presence of platelet/endothelial cell adhesion molecule in a small cell neoplasm should not in isolation be taken as evidence of hematopoietic origin. These results further define the utility of CD31 in the evaluation of human neoplasms.

MOC31 immunoreactivity in primary and metastatic carcinoma of the liver. Report of findings and review of other utilized markers.

Differentiating between primary tumors of the liver and metastatic lesions can, at times, be difficult. Various histochemical and immunohistochemical methods have been used in an effort to better delineate between hepatocellular carcinoma (HCC), especially the microglandular variant, primary cholangiocarcinoma, and metastatic adenocarcinoma; these ancillary studies can yield less than satisfactory results. Recently, anti-MOC31, a monoclonal antibody directed against a cell surface glycoprotein, has been shown to be helpful in distinguishing between adenocarcinoma and mesothelioma. This study addresses whether this antibody might be helpful in distinguishing between HCC, primary cholangiocarcinoma, and metastatic adenocarcinoma in the liver. Formalin-fixed, paraffin-embedded tissue sections from 15 HCC (including 10 microglandular variants), 14 primary cholangiocarcinomas, and 33 metastatic adenocarcinomas (7 colon, 1 lung, 8 breast, 4 GE jct/gastric, 9 pancreas, 2 small intestine, 1 renal, 1 ovary) were immunostained with anti-MOC 31 (1:40, Dako) after protease digestion and biotin block using a modified ABC technique. Positive staining was limited to membrane based reactivity; controls stained appropriately. Immunoreactivity for MOC31 was observed in 14 of 14 cholangiocarcinomas and 33 of 33 metastatic tumors. Staining was diffuse, intense, and readily interpretable, with rare exceptions. All 15 cases of HCC were negative. We conclude that cholangiocarcinoma and metastatic adenocarcinoma from a variety of sites express MOC31; HCC is uniformly negative for this marker. Anti-MOC31 may prove useful in the evaluation of liver neoplasms where primary hepatocellular and adenocarcinoma enter the differential diagnosis; it is not useful in separating primary cholangiocarcinoma from metastatic adenocarcinoma.

Femoral medullary infarction secondary to canine total hip arthroplasty.

OBJECTIVE: To evaluate the prevalence of femoral intramedullary infarction after total hip arthroplasty (THA) and to determine whether any specific femoral morphology predisposes to bone infarction. STUDY DESIGN: Retrospective clinical study. SAMPLE POPULATION: All dogs from our hospital population undergoing THA between 1984 and 1997 with radiographic follow-up available at 1 year or more postoperatively. METHODS: A case control study was conducted within the THA group to determine risk factors predisposing to femoral infarction after THA. Medical records and radiographs were reviewed. Data were collected on clinical parameters, femoral morphology, prosthesis, and bone changes. Radiographic diagnosis was confirmed using histopathology in 11 femora. Radiographs of 50 age-matched control dogs weighing more than 20 kg with coxofemoral degenerative joint disease were randomly chosen to determine the prevalence of bone infarction in nonoperated dogs. RESULTS: Ninety-one dogs with 110 THA were included in the study. Fifteen of the 110 femora with THA had radiographic evidence of infarction (14%). Infarction was not present in any femora in the control group. There was no significant difference in the prevalence of infarction between dogs that received cemented or uncemented prostheses. Clinical signs were not reported in any patient that developed femoral infarction. Young age (P = .03) and a distance between the greater trochanter and nutrient foramen greater than 79 mm (P = .008) predisposed dogs to femoral infarction. Over time, three infarcts decreased in size radiographically, five remained unchanged, and three expanded. An osteosarcoma developed at the site of a bone infarct in one dog. CONCLUSION: Femoral intramedullary infarction occurred in 15 of 110 THA. Young age at the time of THA and a greater distance between the greater trochanter and the nutrient foramen predisposed to infarction. CLINICAL RELEVANCE: Intramedullary infarction occurs after canine THA. These bone infarcts do not appear to cause clinical signs; however, they may present a diagnostic challenge. Malignant transformation could potentially result from medullary infarction.

Angiosarcoma of the mandible: a case report and review of the literature.

Angiosarcoma is a rare malignancy that is characterized by endothelial cell differentiation. In the head and neck area, most of these lesions arise in the scalps of elderly individuals. Less commonly, angiosarcomas can be found within bone. The purpose of this report is to describe an example of angiosarcoma involving the floor of the mouth and right body of the mandible. The histopathologic and immunopathologic features of these lesions are also reviewed.

Phase I trial of exisulind (sulindac sulfone, FGN-1) as a chemopreventive agent in patients with familial adenomatous polyposis.

Exisulind (sulindac sulfone; FGN-1), a metabolite of sulindac without known effects on prostaglandin synthesis, can promote apoptosis and inhibit tumorigenesis in preclinical systems. We performed a Phase I trial of this compound in patients with familial adenomatous polyposis (FAP) to examine the tolerability and safety of this drug in the cancer chemoprevention setting. Six patients each were treated with exisulind at doses of 200, 300, and 400 mg p.o. twice a day. Reversible hepatic dysfunction was noted in four of six patients treated at the 400-mg p.o., twice-a-day dose level, but in only one to two of six patients treated at each of the lower dose levels. The serum half-life of exisulind was 6-9 h; little drug accumulation was noted over time. A nonsignificant trend toward increased apoptosis in polyps was noted at the maximum tolerated dose, but no decrease in polyp numbers or significant effects on cellular proliferation was noted. After treatment, polyps tended to display a "halo" appearance grossly and mucinous differentiation histologically. The maximum safe dose of exisulind is 300 mg p.o. twice a day in patients with subtotal colectomies. Reversible hepatic dysfunction limits further dose escalation. A decrease in polyp numbers could not be demonstrated, but the trend toward increased apoptosis at the MTD and the observation of mucinous change histologically suggest that further investigation of drugs of this class might be warranted.

Canine uncemented porous-coated anatomic total hip arthroplasty: results of a long-term prospective evaluation of 50 consecutive cases.

OBJECTIVE: To evaluate the long-term clinical and radiographic results of a canine uncemented porous-coated anatomic (PCA) total hip arthroplasty (THA). STUDY DESIGN: Prospective study of consecutive clinical patients using survival analysis. ANIMALS: Forty-one dogs that underwent PCA THA; nine had bilateral PCA THA (50 prostheses). METHODS: Gait observation, orthopedic examination, and radiographic assessment were conducted before THA, 6 months after THA, and yearly thereafter. A zonal analysis system was used to document osseous changes in the femur and the acetabulum. Acetabular cup and femoral stem subsidence and migration, femoral canal fill, and implant orientation were measured. Survival analysis of the procedure was conducted. RESULTS: Long-term follow-up was available for 37 dogs (46 prostheses). The median follow-up was 63 months. Limb function was normal for 37 limbs and abnormal for 9 limbs because of dislocation (n = 3), lumbosacral disease (n = 2), degenerative myelopathy (n = 1), autoimmune disease (n = 1), brain tumor (n = 1), or osteosarcoma of the femur (n = 1). All prosthetic stems and cups were fixed by bone ingrowth fixation. Osteolysis was not observed. Bone infarction occurred in five femoral canals (four dogs). The 6-year survival rate for the procedure was 87% (95% confidence interval, 72%-96%). CONCLUSIONS: Long-term fixation of the uncemented PCA acetabular cup and stem is successful in dogs, and long-term clinical function is excellent.

Sulindac sulfone induced regression of rectal polyps in patients with familial adenomatous polyposis.

Sulindac sulfone (Exisulind), a metabolite of the non-steroidal anti-inflammatory drug, sulindac, was evalauted for its effects on the development of rectal polyps in patients with familial adenomatous polyposis. Three cohorts of 6 patients each were given doses of 200, 300, or 400 mg Exisulind twice daily. Hepatotoxicity, shown by elevation in blood transaminase levels, was the dose-limiting toxicity and occurred at the 400 mg bid dose. Due to this toxicity, all patients treated with the 400 mg dose were subsequently reduced to the 200 mg dose level. Subsequently, 2 of the 6 patients were dose-escalated to 400 mg bid dose. The patients were treated with Exisulind for a period of six months. Sixteen of 18 patients had regression of small polyps (> or = 6 mm in diameter) characterized by a flattening of the polyps and a macular "halo" appearance. Histopathologic examination of the polyp biopsy specimens showed a marked increase in the proportion of mucin producing cells in the glands after treatment with Exisulind at all dose levels. Ki-67 staining, a measure of cell proliferation, was higher in the polyps than in normal mucosa. There was no significant change in the proliferation index between baseline and six month values in any of the groups treated with Exisulind or in normal tissues. The median apoptotic labeling index, as determined by the TUNEL technique, was higher in the polyps than in normal-appearing mucosa. Overall, there was no significant change in the apoptotic labeling index between base-line and 6 months in normal-appearing mucosa however, the index in polyps was increased. These results suggest that treatment of FAP patients with Exisulind for a period of six months may lead to regression of small polyps, and that the mechanisms of Exisulind--induced regression appear to be through stimulation of mucus differentiation and apoptosis in glandular epithelium.

An immunohistochemical study of Na+/I- symporter in human thyroid tissues and salivary gland tissues.

The human Na+/I- symporter (hNIS) is the plasma membrane protein that mediates active iodide uptake into several tissues, such as the thyroid and salivary glands. To study the distribution and cellular localization of the hNIS protein, we have generated a polyclonal antibody that could detect the hNIS protein by immunohistochemical staining on tissue sections. In normal thyroids, hNIS expression is heterogeneous, and it is only detected in sporadic thyrocytes of a given follicle. The hNIS protein was not detected in thyroid carcinomas, yet it was detected in the majority of thyrocytes in Graves' thyroids. In salivary glands, hNIS protein was not detected in acinar cells, but it was detected in ductal cells. The hNIS proteins are clustered in the basal and lateral membranes in cells stained positive for hNIS.

Frequent mutation of p16 in squamous cell carcinoma of the head and neck.

RNA was isolated from 22 squamous cell carcinomas (SCCs) obtained from diverse sites within the head and neck and from matched normal tissue where available. Tissue samples were then screened for expression of RNA from tumor suppressor gene p16 by utilizing semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) analysis. p16-Specific PCR amplification products generated from tumor samples were subject to further analysis by direct DNA sequencing to determine if any tumor sample harbored a p16 mutation. The results show the presence of mutations in 10 of 22 (45%) of the tumor samples. Mutations comprise two identical point mutations, two small deletions (1 bp and 2 bp), one single-nucleotide insertion, four larger deletions, and an insertion/deletion. No mutations in p16 have been identified by analysis of PCR products generated from normal matched tissue, suggesting that p16 alterations are generated by somatic mutation and are not germline in origin. All 22 samples were analyzed additionally by immunohistochemistry for nuclear expression of the retinoblastoma (RB) tumor suppressor gene product. Results show lack of RB nuclear expression in only one sample, suggesting that mutation of RB is an infrequent event in the development of SCC of the head and neck (SCCHN).

Single-stage revision using an uncemented, porous-coated, anatomic endoprosthesis in two dogs: case report.

OBJECTIVE: To describe the clinical and radiographic features of septic and aseptic failure of two femoral endoprostheses and their successful revision. STUDY DESIGN: Case report. ANIMALS OR SAMPLE POPULATION: Two skeletally mature male research dogs. METHODS: An uncemented porous-coated anatomic (PCA) endoprosthesis was implanted in a single-stage revision procedure after thorough debridement and lavage of the femoral canal. An autogenous cancellous bone graft was used in dog 2 (aseptic loosening). Serial clinical and radiographic examinations were performed postoperatively. The dogs were euthanatized 1 year (dog 1) and 2 years (dog 2) after revision surgery, and necropsy was performed. High-resolution contact radiographs and histopathologic evaluation of femoral sections were obtained. RESULTS: The cause of implant failure was septic loosening in dog 1 and aseptic loosening in dog 2. In both dogs, clinical function returned to normal after revision. Serial radiographic assessment after revision documented disappearance of the bone pedestal and the periprosthetic lucency. Cancellous hypertrophy seen adjacent to the proximal porous-coated region of the implants provided radiographic evidence of bony fixation. Histological evaluation of femoral sections documented successful implant integration with bone and fibrous tissue. CONCLUSION: Revision with an uncemented implant in a single-stage procedure was successful in the two dogs described in this report. CLINICAL RELEVANCE: This report provides a detailed description of the clinical course and serial radiographic assessment of septic and aseptic loosening of two femoral endoprostheses. Single-stage revision is a potential treatment for either condition as demonstrated by the successful outcome in these two dogs.

Alterations in the expression of alpha6beta4 integrin and p21/WAF1/Cip1 in N-nitrosomethylbenzylamine-induced rat esophageal tumorigenesis.

Integrin alpha6beta4 is altered in many neoplastic cells, but no data exist to show this happens in esophageal neoplasms. To examine the expression of this integrin in rat esophageal tumorigenesis induced by N-nitrosomethylbenzylamine (NMBA), (alpha6 and beta4 expression was evaluated in normal esophageal epithelium, in NMBA-induced preneoplastic lesions, and in papillomas by quantitative reverse transcription (RT)-polymerase chain reaction (PCR) and immunohistochemical analysis. Because the 34 subunit of this integrin has been found to cause cell-cycle arrest by the induction of p21/WAF1/Cip1, the expression of p21/WAF1/Cip1 was also analyzed by RT-PCR. Compared with the levels in normal epithelium, the alpha6A, alpha6B, and beta4 integrin levels in esophageal papillomas were 1.9-, 2.2-, and 2.1-fold lower, respectively. RT-PCR analysis showed no significant differences in integrin levels between preneoplastic and normal samples, and northern blot analysis of the beta4 integrin produced results in agreement with the RT-PCR results. The p21/WAF1/Cip1 level was decreased 1.6-fold in preneoplastic tissues and 3.1-fold in papilloma samples when compared with the mRNA levels in normal epithelium. Immunostaining showed that alpha6beta4 integrin was localized at the basolateral surface of the basal cells in normal esophageal epithelium. In preneoplastic lesions, however, the expression of this integrin was not polarized and was expressed in basal cells as well as in suprabasal cells. Beta4 expression was significantly reduced and alpha6A expression was decreased and delocalized in papillomas. These findings suggest that alteration in alpha6beta4 integrin and p21/WAF1/Cip1 expression may be an important biomarker for tumor progression in NMBA-induced rat esophageal tumorigenesis.