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Biomedical subjects

U A Almagro

Publications and source records attributed to U A Almagro.

At least 19 recordsLinked to original sources

Combined robotic and nonrobotic telepathology as an integral service component of a geographically dispersed laboratory network.

To achieve real-time connectivity between its 8 hopital-based laboratories, Veterans Integrated Service Network (VISN) 12, headquartered in Chicago, IL, has implemented a hybrid dynamic store-and-forward (HDSF) telepathology network that extends across portions of 3 states. The majority of diagnostic telepathology functions are provided to the 3 hospitals (Iron Mountain, MI; Tomah, WI; and North Chicago, IL), which lack on-site pathologists and are serviced by the 4 pathologists located in Milwaukee, WI. In surgical pathology, routine primary diagnosis, frozen section diagnosis, and clinical consultation are provided with telepathology. In addition, autopsy and specialty clinical conferences are frequently performed by using telepathology. Telepathology has been applied to a variety of areas within clinical pathology as well, including protein electrophoresis, immunoelectrophoresis, peripheral blood smears, body fluids, microbiology, and distance learning. Implementation of telepathology has allowed VISN 12 to reach the goal of providing a single standard of accurate and timely pathology service, even at small sites that lack an on-site pathologist.

Computer Communication Networks↗

Telepathology networking in VISN-12 of the Veterans Health Administration.

The Veterans Integrated Service Network (VISN)-12, headquartered in Chicago, has implemented a telepathology network between the eight VISN-12 hospital laboratories and Loyola University Medical School linked by an economical, high-speed wide-area network (WAN). Implementation of the WAN has reduced monthly telecommunications costs in VISN-12 by approximately 67%. In addition to telepathology, the WAN enables real-time teleradiology (general, computer tomography, and ultrasound), telefluoroscopy, telenuclear medicine imaging, telepsychiatry, and other forms of teleconsultation. Current applications of telepathology in VISN-12 include: primary diagnosis and consultation in surgical pathology, interpretation of serum protein electrophoresis and immunofixation gels, provision of support for consolidated microbiology laboratories, review of problematic peripheral blood smears, and distance learning. We have learned a variety of lessons from telepathology. The enthusiasm and technical skill of providers are essential for success. As well, frequent communication and rapid technical support are necessary. Finally, in a supportive environment, telepathology is a tool that can help bring together clinical laboratories with shared missions and goals.

Computer Communication Networks↗

Routine surgical telepathology in the Department of Veterans Affairs: experience-related improvements in pathologist performance in 2200 cases.

OBJECTIVE: To determine whether diagnostic concordance, case deferral rate, and/or time required to review slides changed significantly as telepathologists gained additional experience using a hybrid dynamic/store-and-forward (HDSF) telepathology (TP) system on the 2000 cases following an initial 200 consecutive surgical cases, previously reported. MATERIALS AND METHODS: Gross surgical pathology specimens were prepared by specially trained personnel in Iron Mountain, Michigan. For TP, glass slides were placed on the stage of a robotic microscope at the Iron Mountain VAMC (remote site); control of the motorized microscope was then transferred to a pathologist located 220 miles away at the Milwaukee, Wisconsin, VAMC (host site). For each case, a telepathologist had the option of either rendering a diagnosis or deferring the case for later analysis by conventional light microscopy (LM). After the slides were read by TP and a surgical pathology report had been generated (for nondeferred cases), the slides were transported to Milwaukee, where they were reexamined by the same pathologist, now using LM. When there was disagreement between the TP and LM diagnosis, a supplemental or revised report was issued, and the referring physician was notified by telephone immediately. All supplemental and revised reports were reviewed by a third pathologist in the group. The slides were then reviewed by the pathology group practice or, when there was no consensus, by the Armed Forces Institute of Pathology to establish a "truth" diagnosis. To determine changes in telepathologist performance with experience after the initial start-up of the service, their performance in handling 10 consecutive sets of 200 surgical pathology cases was analyzed. RESULTS: Concordance rates for clinically significant TP and LM diagnoses were high for all 10 sets, ranging from 99% to 100%. Comparing the first set (Cases 201-400) with the last set (Cases 2001-2200), viewing times per case were reduced from 10.26 min to 3. 58 min. Viewing times per slide were reduced from 3.44 min to 1.13 min per slide, comparing the first and last sets. Case turnaround times (TAT) decreased from 2.46 days to < or =1.5 days. CONCLUSION: Thes results demonstrate that improvements in TP services occur over time as the result of additional experience using the TP system. The high diagnostic concordance and low rate of case deferral lend additional support to the proposal that a host-site pathologist using HDSF TP can substitute effectively for an on-site pathologist as a service provider.

Clinical Competence↗

Telepathology.

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Humans↗

L-arginine uptake and metabolism by lung macrophages and neutrophils following intratracheal instillation of silica in vivo.

Nitric oxide (NO) has been associated with lung inflammation following exposure to silica. L-arginine can be converted to NO and L-citrulline by nitric oxide synthase (NOS), or into urea and L-ornithine by arginase. We tested the hypothesis that after instillation of silica into rat lungs in vivo, lung inflammatory cells increase L-arginine metabolism by both NOS and arginase, which is associated with an increase in L-arginine uptake. We isolated lung inflammatory cells 3 d after silica or saline (control) exposure. The uptake of [3H]L-arginine at 24 h by cells from silica-exposed lungs (73.9 +/- 4.8%) was significantly greater than uptake by control cells (24.7 +/- 2.2%; P < 0.05) and was a saturable process. The greater [3H]L-arginine uptake by cells from silica-exposed lungs was associated with greater NO and urea production than by control cells. The uptake of [3H]L-arginine by cells from control or silica-exposed lungs was blocked in a dose-dependent manner by L-ornithine (an inhibitor of L-arginine transport) and by Nomega-nitro-L-arginine methyl ester (L-NAME) (an NOS inhibitor), but not by L-valine (an arginase inhibitor). The production of NO by cells from silica-exposed lungs was completely blocked by L-NAME. The addition of L-arginine to media resulted in dose-dependent production of NO and urea. The results show that lung inflammatory cells increase L-arginine uptake and metabolism by both NOS and arginase following in vivo silica exposure. The increase in L-arginine uptake may represent a mechanism to maintain an intracellular supply of this amino acid. NO can react to generate peroxynitrite, a potential mediator of lung injury following silica exposure.

Animals↗

Dynamic-robotic telepathology: Department of Veterans Affairs feasibility study.

In this retrospective study, we assess the accuracy, confidence levels, and viewing times of two generalist pathologists using both dynamic-robotic telepathology and conventional light microscopy (LM) to render diagnoses on a test set of 100 consecutive routine surgical pathology cases. The objective is to determine whether telepathology will allow a pathology group practice at a diagnostic hub to provide routine diagnostic services to a remote hospital without an on-site pathologist. For TP, glass slides were placed on the motorized stage of the robotic microscope of a telepathology system by a senior laboratory technologist in Iron Mountain, MI. Real-time control of the motorized microscope was then transferred to a pathologist in Milwaukee, WI, who viewed images of the glass slides on a video monitor. The telepathologists deferred rendering a diagnosis in 1.5% of cases. Clinically important concordance between the individual diagnoses rendered by telepathology and the "truth" diagnoses established by rereview of glass slides was 98.5%. In the telepathology mode, there were five incorrect diagnoses out of a total of 197 diagnoses. In four cases in which the telepathology diagnosis was incorrect, the pathologist's diagnosis by LM was identical to that rendered by telepathology. These represent errors of interpretation and cannot be ascribed to telepathology. The certainty of the pathologists with respect to their diagnoses was evaluated over time. Results for the first 50 cases served as baseline data. For the second 50 cases, confidence in rendering a diagnosis in the telepathology mode was essentially identical to that of making a diagnosis in the LM viewing mode. Viewing times in the telepathology mode also improved with more experience using the telepathology system. These results support the concept that an off-site pathologist using dynamic-robotic telepathology can substitute for an on-site pathologist as a service provider.

Feasibility Studies↗

Use of telepathology for routine surgical pathology review in a test bed in the Department of Veterans Affairs.

BACKGROUND: Routine surgical pathology review by telepathology could be an important service component of multi-institutional pathology laboratory systems. Such service networks would increase access for rural hospitals without on-site pathologists to a broader range of pathology services on a daily basis. METHODS: In this clinical trial, we analyzed the diagnostic accuracy, deferral rates, and viewing times of two generalist pathologists using a hybrid dynamic/store-and-forward (HDSF) telepathology (TP) system to render diagnoses in real time on 200 consecutive surgical cases. The objective was to assess the efficacy of TP in providing diagnostic surgical pathology services to a remote hospital without an onsite pathologist. Surgical pathology specimens underwent gross preparation by specially trained personnel. When appropriate, this was done under the video supervision of a telepathologist. For TP, glass slides were placed on the stage of a robotic microscope at the Iron Mountain (MI) Department of Veterans Affairs Medical Center (VAMC) (remote site); control of the motorized microscope was then transferred to a pathologist located 220 miles away at the Milwaukee VAMC (host site). For each case, the telepathologist had the option of rendering a diagnosis or deferring the case for later analysis by conventional light microscopy (LM). After the slides were read by TP and a surgical pathology report had been generated, the slides were transported to Milwaukee, where they were reexamined by the telepathologist using LM and then by the pathology group practice or, when there was no consensus, by an outside consultant to establish a "truth" diagnosis. RESULTS: Compared with the consensus ("truth") diagnosis, clinically important and overall concordance were 99.0% and 97.4%, respectively, by TP, and clinically important and overall concordance were 100.0% and 98.5%, respectively, by LM. The deferral rate was 2.5%. Examining glass slides by HDSF telepathology took an average of 4.43 minutes per slide and 12.09 minutes per case. CONCLUSION: The high diagnostic accuracy and low rate of case deferral support the proposal that an offsite pathologist using HDSF telepathology can substitute effectively for an onsite pathologist as a service provider.

Biopsy↗

Hydroxyl radical production and lung injury in the rat following silica or titanium dioxide instillation in vivo.

The hydroxyl radical (.OH) is a highly reactive oxygen free radical that has been implicated as a cause of lung injury following exposure to silica and silicates. Despite evidence that silica generates .OH in vitro, there has been no previous demonstration of in vivo production of .OH after exposure to nonfibrous mineral oxide dusts. We tested the hypothesis that instillation of silica into rat lungs is associated with greater .OH production and acute lung inflammation in vivo relative to the instillation of a less toxic nonsilicate particle, titanium dioxide. The production of .OH in the lungs following dust instillation was measured using sodium salicylate as an .OH trap. Seven days after dust exposure, the rats were given intraperitoneal salicylate, the lungs isolated, and salicylate hydroxylation products (2,3- and 2,5-dihydroxybenzoic acid), reflecting .OH, were measured. There was significantly more 2,3-dihydroxybenzoic acid in silica-exposed lungs compared with lungs instilled with titanium dioxide. In addition, the instillation of silica into rat lungs in vivo was associated with a greater acute inflammatory response. We conclude that following in vivo exposure, silica stimulates greater .OH production relative to the less toxic particle, titanium dioxide. These differences in .OH generation correspond to disparities in acute lung inflammation.

Animals↗

Richter's syndrome presenting as primary central nervous system lymphoma. Transformation of an identical clone.

The development of a central nervous system (CNS) large cell lymphoma in a patient simultaneously diagnosed with chronic lymphocytic leukemia (CLL) is reported. Although differences in phenotypic expression were demonstrated in study of the peripheral blood and CNS disease, identical immunoglobulin gene rearrangements were identified, providing evidence for evolution of two morphologically distinct neoplasms from the same clone. Beyond histologic transformation, acquisition of an aneuploid cell population in the CNS tumor was demonstrated by analysis of DNA content. Isolated parenchymal involvement of the CNS by large cell transformation of CLL has not been previously described; its relationship to CNS lymphoma and Richter's syndrome are reviewed.

Aged↗

Idiopathic pulmonary fibrosis. A rare cause of scintigraphic ventilation-perfusion mismatch.

A case of idiopathic pulmonary fibrosis with multiple areas of mismatch on ventilation-perfusion lung imaging in the absence of pulmonary embolism is presented. Idiopathic pulmonary fibrosis is one of the few nonembolic diseases producing a pulmonary ventilation-perfusion mismatch. In this condition, chest radiographs may not detect the full extent of disease, and xenon-133 ventilation imaging may be relatively insensitive to morbid changes in small airways. Thus, when examining patients with idiopathic pulmonary fibrosis, one should be aware that abnormal perfusion imaging patterns without matching ventilation abnormalities are not always due to embolism. In this setting, contrast pulmonary angiography is often needed for accurate differential diagnosis.

Diagnosis, Differential↗

Tuberculous epididymitis occurring 35 years after renal tuberculosis.

An unusual case of tuberculous epididymitis occurring 35 years after renal tuberculosis is reported. The possible mechanisms of this delayed presentation of the epididymal lesion are discussed. This case emphasizes the importance of adequate treatment as well as long-term followup of patients with genitourinary tuberculosis.

Aged↗

Metastatic tumors involving testis.

Two cases of metastatic tumors involving the testis are reported: one from an adenocarcinoma of the prostate and the other from an adenocarcinoma of the colon. The first was found incidentally in the orchiectomy specimen done for prostatic cancer while the other was noted clinically as a part of a widely disseminated disease. Although there are numerous pathways through which tumors may metastasize to the testis, the occurrence of testicular metastasis is extremely rare. The reason for this rarity remains unknown.

Adenocarcinoma↗

Primary renal carcinoid tumor.

A case of primary renal carcinoid tumor in a sixty-seven-year-old man is presented. Radical nephrectomy removed the primary disease, but hepatic metastases developed and the patient subsequently died. Review of the literature disclosed 8 other cases of primary renal carcinoid. Three of these had metastatic spread.

Aged↗

Argyrophilic, 'carcinoid-like' prostatic carcinoma. An immunocytochemical study.

Four cases of argyrophilic or carcinoid-like prostatic carcinoma were studied immunocytochemically, using immunoperoxidase stains for prostatic-specific antigen, neuron-specific enolase, hydroxytryptamine (serotonin), somatostatin, and adrenocorticotropic hormone. All four showed strong positive reaction to prostatic-specific antigen and uniformly negative results with neuron-specific enolase, hydroxytryptamine, somatostatin, and adrenocorticotropic hormone. These findings lend further support to the concept that this particular prostatic tumor is truly a carcinoma that somehow manifests a carcinoid-like histomorphology, but does not possess evidence of true neuroendocrine or carcinoidal nature.

Adenocarcinoma↗

Argyrophilic prostatic carcinoma. Case report with literature review on prostatic carcinoid and "carcinoid-like" prostatic carcinoma.

An unusual prostatic neoplasm characterized by a carcinoid-like light microscopic pattern together with argyrophilia of tumor cells is described. Immunoperoxidase stain for prostatic specific antigen, however, was positive, indicating that this neoplasm was an argyrophilic prostatic carcinoma. Although the clinical significance of a carcinoid-like pattern and/or argyrophilia in prostatic carcinoma is currently unknown, pathologic recognition of these features is of paramount importance because prostatic carcinoma with these features has to be distinguished from true primary prostatic carcinoid tumor or, in areas of metastasis, from metastatic carcinoid originating from other sites such as the gastrointestinal or respiratory tracts. The value of the immunoperoxidase technique for prostatic specific antigen as well as prostatic acid phosphatase in this differentiation is stressed.

Adenocarcinoma↗

Splenic phagocytic function after partial splenectomy and splenic autotransplantation.

We investigated splenic reticuloendothelial activity after splenic preservation procedures to determine their effect upon the phagocytic function of the spleen. We performed the following procedures in Sprague-Dawley rats: sham laparotomy, total splenectomy, hemisplenectomy, subtotal splenectomy, or total splenectomy with intraperitoneal splenic autotransplantation. At nine weeks after operation, phagocytic function of the spleen was determined by measuring radiocolloid uptake. Mean (+/- SEM) splenic phagocytic indices for sham laparotomy (41.2 +/- 2.9), hemisplenectomy (44 +/- 2.9), and subtotal splenectomy (43.2 +/- 5.2) were similar; however, the phagocytic index was reduced markedly after autotransplantation (15.8 +/- 2.2). These data demonstrate that the phagocytic function of the spleen after hemisplenectomy and subtotal splenectomy correlates highly with the weight of the splenic remnant; however, phagocytic function after autotransplantation remains reduced even after accounting for differences in splenic weight.

Animals↗