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PubMed1997

Evaluation of the Roche AMPLICOR MTB assay for the detection of Mycobacterium tuberculosis in sputum specimens from prison inmates.

The reliability of the Roche Mycobacterium tuberculosis polymerase chain reaction (PCR) assay (AMPLICOR MTB) for the diagnosis of pulmonary tuberculosis was evaluated by testing expectorated sputum specimens from 187 inmates in Texas state prisons and comparing the results to culture and medical history. Of the 80 specimens that were culture positive for mycobacteria, 36 specimens from 16 patients grew M. tuberculosis. Forty-six specimens were smear positive for acid-fast bacilli (AFB), and of these, M. tuberculosis was isolated from 24. On initial testing, 52 specimens were PCR positive. Thirty-one of these 52 were culture positive for M. tuberculosis, and 21 were culture negative, resulting in a PCR sensitivity and specificity of 86.1 and 96.1%, respectively. After resolving discrepancies by review of the medical history and repeat testing, PCR sensitivity, specificity, and positive and negative predictive values, respectively, were 92.8, 99.8, 98.1, and 99.2%. For AFB smear-positive specimens, the sensitivity, specificity, and positive and negative predictive values, were 95.8, 100, 100, and 93.3, respectively; whereas, for AFB smear-negative specimens, these values were 87.5, 99.7, 95.5, and 99.4%, respectively. These results confirm the reliability of the AMPLICOR MTB assay for direct detection of M. tuberculosis in AFB smear-positive sputum specimens and suggest a potential role in evaluating AFB smear-negative sputum specimens.

Humans↗
PubMed1998

Optimal recovery of cytomegalovirus from urine as a function of specimen preparation.

Cytomegalovirus (CMV) is a significant pathogen among immunocompromised patients. We compared supernatant and sediment fractions of centrifuged urine for the optimal recovery of CMV by shell vial culture and polymerase chain reaction (PCR). Of 336 urine specimens, 31 (9.23%) were positive by shell vial culture; of these 29 (93.5%) were identified using the sediment fraction and 17 (54.8%) using the supernatant fraction (p = 0.001, chi2). Of the 29 positive sediment fraction specimens, 24 (82.8%) were identified as CMV positive at 24 h and 5 (17.2%) were identified as positive at 48 h. Two (0.064%) of the total 31 positive specimens were lost to microbial contamination in the sediment inoculated cultures. Of the 17 supernatant fraction specimens, 9 (53.9%) were identified as CMV positive at 24 h and 8 (47.1%) were identified as positive at 48 h. Fourteen (45.2%) of the total 31 positive specimens were lost to either toxicity or microbial contamination in the sediment-inoculated cultures. Thirty-four CMV culture-positive specimens were tested by PCR; 5 of these specimens (14.7%) were PCR negative for both sediment and supernatant fractions; 26 (76.5%) were found to be positive using the sediment fraction and negative using the supernatant; 3 (8.8%) were PCR positive for both the sediment and the supernatant. None of the 34 was identified as positive using the supernatant fraction only (p = 0.001, chi2). These findings demonstrate that the method of specimen preparation can significantly affect the outcome of diagnostic testing for CMV from urine specimens.

Antigens, Viral↗
PubMed1999

Evaluation of ELVIS HSV ID/Typing System for the detection and typing of herpes simplex virus from clinical specimens.

BACKGROUND: Herpes simplex virus (HSV) is a common pathogen with two serotypes: HSV-1 and HSV-2. HSV infection does not pose much of a threat to an immunocompetent host but to an immunocompromised host or a neonate the infection can be fatal. The Enzyme-Linked Virus Inducible System (ELVIS) employs a genetically altered baby hamster kidney (BHK) cell line that allows for the rapid overnight detection of HSV but also includes an immunofluorescent stain for the simultaneous detection and typing of HSV-1 and HSV-2. OBJECTIVE: To evaluate the ELVIS HSV ID/Typing System in comparison with HSV identification and typing in primary rabbit kidney (PRK) cells grown in shell vials. STUDY DESIGN: Over a period of 6 weeks, 130 specimens were submitted to the diagnostic virology laboratory and cultured for the presence of HSV. Two PRK shell vials and one ELVIS BHK shell vial were inoculated with patient specimen. PRK shell vials were observed for cytopathic effect (CPE) for up to 4 days. When CPE was observed the PRK shell vials were fixed and one shell vial was stained with HSV-1 monoclonal antibody (Mab) and the other was stained with HSV-2 Mab. The coverslips were observed under the fluorescent microscope for specific apple-green fluorescence. The BHK shell vials were incubated overnight, fixed, and stained with galactopyranoside (X-Gal). If blue cells were present, the specimen was positive for HSV. The coverslip was then observed under the fluorescent microscope for the presence of specific apple-green fluorescence, indicating HSV-2. If no specific apple-green stain was observed, the coverslip was stained with a fluorescent conjugated goat anti-mouse IgG to determine the presence of HSV-1. RESULTS: Of the 130 specimens, PRK shell vials detected 43 positive HSV; 30 were HSV-2 and 13 were HSV-1. The ELVIS BHK shell vials detected 42 positive HSV; 30 were HSV-2 and 12 were HSV-1. One low titer specimen was not identified as being HSV positive. Two specimens were not directly typed by the ELVIS system. One specimen had only one blue cell present and did not show specific staining for either HSV-1 or HSV-2. The other specimen had only five blue cells present and only one fluorescent cell present that was difficult to type. As suggested by the manufacturer's instructions, both specimens that were not directly typed were re-grown overnight from their supernatants and were correctly identified and typed. CONCLUSION: The ELVIS HSV ID/Typing System is a rapid, highly specific and sensitive method of overnight HSV detection and typing.

Animals↗
PubMed1997

An assessment of the usefulness of serum prostate-specific antigen level and cancer volume in biopsy specimens to predict the extent of prostate cancer.

OBJECTIVE: To evaluate the usefulness of the combination of serum prostate-specific antigen (PSA) and cancer volume in biopsy specimens as markers to predict the extent of prostate cancer. PATIENTS AND METHODS: Of patients presenting at our hospital with urinary symptoms suggesting prostatic disease, 311 (median age 70 years, range 42-88) with either nodules in the prostate detected by digital rectal examination or with elevated serum PSA levels (> 2.0 ng/mL) underwent systematic biopsy; 69 had prostate cancer. The cancer volume in the biopsy specimens was examined pathologically by measuring the percentage of the biopsy core involved with cancer, the length of cancer tissue per biopsy core and the percentage of cancer in the biopsy specimen. The relationship of serum PSA level, cancer volume in the biopsy specimen and the extent of disease was examined. RESULTS: The volume of cancer in the biopsy specimens increased with increasing serum PSA concentration and the incidence of skeletal metastasis. The number of patients with extraprostatic disease or bony metastasis was significantly higher for these Japanese patients with a serum PSA of < 10 ng/mL. All six patients with a positive bone scan and who had a serum PSA level of < 10 ng/mL had a larger volume of cancer in their biopsy specimens. Among patients who underwent radical prostatectomy and pelvic lymphadenectomy, the incidence of extraprostatic disease increased with the value of each biopsy variable. Among patients with similar serum PSA levels, those showing higher values for the biopsy variables also showed extraprostatic disease. Among those with extraprostatic disease, seminal vesicles were involved by cancer in four of six patients with > 40% positivity in the biopsy cores, > 1.5 mm of cancer per biopsy core or > 20% cancer in the biopsy specimens. Lymph node metastasis was found in four of five patients with serum PSA levels of > 20 ng/mL and a large cancer volume in the biopsy specimen. CONCLUSIONS: These results indicate that a combination of serum PSA level and cancer volume in the biopsy specimen could be useful markers for predicting the extent of prostate cancer.

Adult↗
PubMed1999

[The demonstration of microcalcification in breast core biopsies: DIMA specimen radiography (7x) compared to the histopathological findings].

PURPOSE: Comparing the sensitivity in detecting microcalcifications in stereotactically guided core biopsy specimen of the breast of direct magnification (DIMA) specimen radiography (x7) with the histological examination. MATERIALS AND METHODS: In 52 patients 509 stereotactically obtained core biopsy (14-gauge) specimens of the breast were radiographed by direct magnification (DIMA) specimen radiography (x7) and examined histologically. RESULTS: In 188 specimen microcalcifications were detected by magnification radiography compared to 98 by histological examination. Only 3% of the specimen microcalcifications were seen exclusively in the histological examination. In core biopsies with malignancy the relative proportion of biopsies with radiologically detected microcalcifications was increased (59% versus 32%). CONCLUSION: Concerning the detection of microcalcifications in core biopsy specimen of the breast, the direct magnification (DIMA) radiography (x7) was superior compared to the histological examination. Due to the high relative proportion of biopsies with radiologically detected microcalcification and malignancy, we recommend a comprehensive histological examination of these specimen. Confirmation of microcalcifications in core biopsies should be achieved by magnification radiography to prove that the suspicious area in the breast was truly sampled. Specimen radiography simultaneously with the biopsy procedure can reduce the number of punctures in the process of documenting the presence of calcifications early in the biopsy procedure.

Biopsy↗
PubMed2002

Specimen morcellation after laparoscopic radical nephrectomy: confirmation of histologic diagnosis using needle biopsy.

BACKGROUND AND PURPOSE: Laparoscopic radical nephrectomy (LRN) is being increasingly offered for the management of renal-cell carcinoma (RCC). Specimen removal may be performed through a small or hand-port incision or by specimen morcellation. Limited studies exist addressing the accuracy of histopathologic diagnosis in morcellated renal tumors. Because of concerns about the lack of a diagnosis secondary to the morcellation process, we performed premorcellation needle biopsies to obtain nondisrupted tissue for pathologic analysis. Herein, we compare the histopathologic diagnosis achieved via needle biopsy prior to morcellation with that of the final specimen. PATIENTS AND METHODS: Following successful laparoscopic resection, specimens were entrapped in a Lapsac. Needle biopsies were performed manually through the mouth of the Lapsac, and morcellation was then done in some patients using manual and mechanical methods. The histopathologic diagnoses in the needle biopsy specimens and the morcellated material were compared. RESULTS: Laparoscopic radical nephrectomy with specimen morcellation was performed in 15 patients. Nine patients had premorcellation needle biopsies. Eight of these biopsies had sufficient tissue for diagnosis of RCC. This finding correlated with final diagnosis from the morcellated material. Perinephric fat invasion was identified in three morcellated specimens. CONCLUSIONS: Needle biopsy prior to specimen morcellation confirmed the histologic diagnosis of the morcellated specimen. This finding suggests that such histopathology material is adequate for diagnosis and may make premorcellation needle biopsy redundant.

Biopsy, Needle↗
PubMed2006

The impact of assessing specimen adequacy and number of needle passes for fine-needle aspiration biopsy of thyroid nodules.

Fine-needle aspiration biopsy (FNAB) of thyroid nodules is a safe, cost-effective procedure but the rates of inadequate cytology specimens range from approximately 1% to 15%. This study tests the hypothesis that ultrasonographically (US) guided FNAB and onsite assessment of cytology improves the adequacy rate of FNAB. A retrospective analysis was performed on 693 thyroid FNAB specimens obtained with and without ultrasound guidance and with or without onsite cytology assessment. Overall, 29 specimens (4%) were inadequate for diagnosis. Among 163 cystic nodules and 530 solid nodules, inadequacy rates were 15% (n = 24) and 1% (n = 5) respectively (p = 0.0001). An onsite assessment of cytology for adequacy was done in 550 cases (83%), which was more accurately performed by a cytopathologist (97%) than a cytotechnologist (93%, p = 0.015). With US-guided FNAB, 3% of the cytology specimens were inadequate, compared to a 7% rate when US was not done (p = 0.003). The mean number of needle punctures necessary for an adequate specimen was 3.8 +/- 0.06 (median, 3.0; range, 1-11), which was different among various types of doctors, ranging from 3.2 +/- 0.07 to 5.4 +/- 0.12 (p = 0.001 analysis of variance [ANOVA]). The fewest number of needle passes to achieve an adequate specimen were required by university endocrinologists and pathologists working together (average, 3.2 +/- 0.07; median, 3.0; range, 1-11). Sample inadequacy rate varied significantly among physician groups, ranging from 3% to 18% (p = 0.0001 ANOVA). Stepwise regression analysis showed that onsite assessment of cytology, US-guided FNAB (p = 0.16), and cystic nature of the nodule (p < 0.0001 for all) correlated with adequacy of the specimen. We conclude that US-guided FNAB with onsite evaluation of cytology specimens substantially increases the adequacy of cytology specimens and decreases the number of required needle passes, which ultimately reduces patient discomfort and diagnostic errors, thus raising the question as to whether this should eventually become the standard of care. We believe this is a goal that training programs should strive to achieve.

Adolescent↗
PubMed1999

Perineural invasion in prostate needle biopsy specimens. Correlation with extraprostatic extension at resection.

The significance of perineural invasion in prostate needle biopsy specimens for predicting extraprostatic extension is controversial. We correlated the presence of perineural invasion in needle biopsy specimens from 340 men with the presence of extraprostatic extension in corresponding radical prostatectomy specimens. Perineural invasion was present in 57 biopsy specimens. The sensitivity of perineural invasion for predicting extraprostatic extension was 32%, the specificity 88%, and the positive predictive value 42%. Biopsy specimens with perineural invasion had significantly more core specimens involved with tumor and higher biopsy-determined Gleason scores than those without invasion. Biopsy specimens with perineural invasion were significantly more likely to show extraprostatic extension and Gleason scores were higher in the resection specimens than those without perineural invasion. Multivariate logistic regression analysis showed that perineural invasion remained an independent predictor of extraprostatic extension. However, in multivariate analysis, including preoperative serum prostate-specific antigen (PSA) for 173 of the patients, the only independent predictor of extraprostatic extension was PSA. While perineural invasion in biopsy specimens is a predictor of extraprostatic extension at resection that is independent of other histologic features, the positive predictive value is low and it is not an independent predictor when serum PSA is included.

Adult↗
PubMed1975

Cellular composition of the nipple aspirate specimen of breast fluid. I. The benign cells.

A nipple aspirator device was used to obtain breast secretions for cytologic examination, as well as for viral and biochemical analysis. Examination of the first 1,456 specimens from 796 women revealed ductal epithelium in 54%. Ductal epithelial cells were often absent in specimens from normal women; however, 78.5% of women with benign breast disease on tissue biopsy had specimens containing ductal epithelium. Apocrine metaplastic cells were a further indication of the presence of breast disease, and were rarely found in specimens from asymptomatic women. Foam cells were often abundant in specimens from normal breasts, but were found in decreased numbers in specimens from women benign breast disease. Differences in the occurrence of ductal epithelial cells, apocrine metaplastic cells, and foam cells suggest an alteration in the rate of maturation of ductal epithelium in women with both benign and malignant breast disease. The finding of a relative abundance of cells in nipple aspirate specimens from women with breast disease and few or no cells in specimens from women with normal breasts is believed to be of great importance in the cytologic evaluation of nipple aspirate specimens.

Body Fluids↗
PubMedDate not supplied

Analysis of spleen specimens for carbon monoxide.

Crucial to the investigation of aircraft fatalities is the analysis of biological specimens for carbon monoxide (CO). In many cases, blood specimens are unavailable or unsuitable for analysis, and the testing of an alternate specimen for CO becomes necessary. Spleen specimens provide a rich source of red blood cells and hence can be a primary substitute for blood. To verify this, 40 paired blood and spleen specimens were analyzed for CO by using a gas chromatographic method. Ten specimens with a spleen CO saturation level (sat.) of less than 10% were associated with corresponding blood specimens with CO sat. less than 10%. Fifteen of the 18 spleen specimens with CO sat. greater than 29% were associated with blood specimens with greater than 48% sat. Results were inconclusive when the spleen CO sat. was between 10 and 29%. We concluded that spleen CO sat. can reflect blood CO sat. in certain situations, particularly when spleen CO sat. is high.

Carbon Monoxide↗
PubMed2006

Prevalence of use study for amphetamine (AMP), methamphetamine (MAMP), 3,4-methylenedioxy-amphetamine (MDA), 3,4-methylenedioxy-methamphetamine (MDMA), and 3,4-methylenedioxy-ethylamphetamine (MDEA) in military entrance processing stations (MEPS) specimens.

The Roche Abuscreen Onlinetrade mark Amphetamine immunoassay (IA), modified to include sodium periodate, and the Microgenics DRI Ecstasy IA were used to determine the prevalence of amphetamine (AMP), methamphetamine (MAMP), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxyethylamphetamine (MDEA) in urine specimens from applicants seeking to join the United States Armed Forces. Over a 4-month period, a total of 85,658 specimens were IA screened using the Department of Defense 500 ng/mL administrative cutoff level for AMP and MDMA. All presumptively positive specimens were confirmed using a solid-phase extraction procedure coupled with simultaneous analysis of AMP, MAMP, MDA, MDMA, and MDEA by fast gas chromatography-mass spectrometry using the same cutoff levels as the IA. The Roche Online Amphetamine IA identified 216 specimens as presumptively positive; of these, 70 specimens confirmed positive for AMP and 87 specimens confirmed positive for AMP and/or MAMP, resulting in a confirmation rate of 73%. The Microgenics DRI Ecstasy IA identified eight specimens as presumptively positive; of these, five specimens confirmed positive for MDMA and/or MDA, resulting in a confirmation rate of 63%. The total use prevalence for AMP, MAMP, MDA, MDMA, and/or MDEA in military entrance processing stations specimens over the testing period was determined to be 0.19%.

Amphetamines↗
PubMedDate not supplied

Drug population in one thousand geographically distributed urine specimens.

Hundreds of drugs and other substances are excreted in urine. In a comprehensive drug screen, it is impossible to identify every detectable substance. In order to delineate the most commonly detected drugs, approximately 1000 urine specimens from geographically distributed clinical laboratories were analyzed for drug substances. Twenty-nine (29) clinical laboratories submitted up to 76 consecutive urine specimens found to be positive for substances other than nicotine and caffeine. Specimens were analyzed by thin layer chromatography and special procedures for salicylates, benzoylecgonine, PCP, benzodiazepines, and cannabinoid metabolites. Every specimen was also tested for opiates, PCP, and cannabinoid metabolites by an enzyme immunoassay procedure. The total number of drugs detected in 1000 specimens was 3014, an average of three drugs per specimen; and 110 different drugs were identified. Of these, 50 drugs accounted for 95% of the total detected; 21% of the specimens contained cannabinoid metabolites, and 4% of the specimens contained cocaine and/or benzoylecgonine. Most of the specimens were routine, and only 4% originated from comatose patients.

Humans↗
PubMed2004

Influence of the image quality deterioration of a tilted thick specimen on electron tomography.

In electron tomography (ET) based on a transmission electron microscope, the effective thickness of a specimen increases with the tilt angle and, therefore, the projection quality may deteriorate because of electron scattering. The information-missing region, however, can be reduced by broadening the specimen tilt range. To clarify the general influence of these effects on ET, the projection quality varying with the tilt angle was quantitatively evaluated for a 5-microm thick specimen observed with a 3 MV ultrahigh-voltage electron microscope. Simulations of three-dimensional reconstruction were then performed for different specimen thicknesses and tilt ranges. As a result, the ET accuracy was shown to decrease as the specimen thickness increased. However, an optimum specimen-tilt range, at which ET could reach its highest accuracy, was found to exist and become small with the increase of the specimen thickness. The presented results are helpful for determining the specimen thickness limitation on the ET resolution and improving the ET fidelity of thick specimens.

Computer Simulation↗
PubMed1996

Effects of the serotonin2 receptor agonist DOI on skeletal muscle specimens from malignant hyperthermia-susceptible patients.

BACKGROUND: Administration of serotonin2 (5-HT2) receptor agonists in pigs triggers malignant hyperthermia (MH) and psychotic-like behavior. Both can be reduced by 5-HT2 receptor antagonists. Furthermore, an increase in the plasma concentration of 5-HT has been found during onset of halothane-induced MH in pigs. Therefore, in this study, the in vitro effects of the 5-HT2 receptor agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) were investigated in muscle specimens from MH-susceptible (MHS) and -negative (MHN) patients. METHODS: After MH classification using the caffeine-halothane contracture test (CHCT), surplus muscle specimens from 23 MHS and 17 MHN patients were used to examine the effects of DOI. In the first study, DOI was added to the bath in a concentration of 0.02 mM. In a second experiment, muscles were preincubated for 60 min with 0.02 mM DOI, and subsequently, halothane was added incrementally to the organ bath (0.11-0.22-0.44 mM) for 15 min according to the CHCT protocol. The in vitro effects of DOI on contracture development and muscle twitch were measured for 120 min in both investigations. RESULTS: Muscle specimens form all patients developed contractures after administration of DOI, characterized by a significantly earlier development of contracture in MHS (16.8 +/- 1.7 min) than in MHN (66.3 +/- 5.8 min) muscles (P < 0.05). There was no overlap between the groups in the range of times. The onset of contracture development after DOI was prolonged by halothane in specimens from MHN patients (89.7 +/- 5.6 min) but not MHS patients. Preincubation with DOI increased the halothane-induced contractures in specimens from MHS patients compared to the results of the CHCT. The contracture development in specimens from MHS patients was larger than from MHN patients. At the end of the experiment, contractures had reached a maximum of 12.9 +/- 1.1 mN in specimens from MHS and 5.3 +/- 0.6 mN in MHN patients (P < 0.05). The additional administration of halothane led to significantly increased contractures in specimens from MHS individuals (15.9 +/- 0.9 mN) at 120 min. However, the contracture development decreased significantly to 3.1 +/- 0.4 mN in MHN muscles. Muscle twitch after DOI administration was reduced significantly in specimens from MHS and MHN patients. CONCLUSIONS: A functional or structural altered serotonin system might be involved in the development of MH in humans.

Adolescent↗
PubMedDate not supplied

High resolution CT mammography of surgical biopsy specimens.

PURPOSE: Our goal was to assess the performance of high resolution CT on breast biopsy specimens before considering the reevaluation of refined CT techniques in patients with breast abnormalities. METHOD: High resolution CT was done in 44 surgical biopsy specimens following conventional X-ray specimen mammography. The specimens comprised 38 palpable and nonpalpable soft tissue abnormalities with mean size of 19 mm and 6 specimens with clustered microcalcifications only. There were 21 carcinomas, 10 fibroadenomas, and 13 other benign conditions. Evaluation of CT and conventional images was done separately, and a feature-grading list was used to compare the two modalities. RESULTS: In fatty specimens, grading of morphologic features of masses and the confidence to detect a soft tissue abnormality were equal with both techniques. CT significantly improved the confidence to detect a mass in 17 specimens with dense tissue: On a scale of 0-10, the mean score for detection was 3.8 with radiography and 5.8 with CT (p<0.008). For clustered microcalcifications, X-ray was superior to CT. The mean CT attenuation of 18 malignant masses (82 HU) was significantly lower than the mean attenuation of 10 fibroadenomas (131 HU; p = 0.003). CT scans of the American College of Radiology test phantom met the requirements for X-ray accreditation. CONCLUSION: For soft tissue abnormalities, CT specimen mammography performed equally as or better than specimen radiography. These in vitro results suggest potential advantages for increased sensitivity and specificity with CT and justify further investigations.

Biopsy↗
PubMed2002

Ultrastructure of the human intervertebral disc during aging and degeneration: comparison of surgical and control specimens.

STUDY DESIGN: Human intervertebral disc tissue from the annulus was obtained in a prospective study investigating the ultrastructural features of disc cells and extracellular matrix. Experimental studies were approved by the authors' Human Subjects Institutional Review Board. Discs were obtained from surgical specimens and control donors. OBJECTIVE: To compare the cellular and extracellular matrix characteristics of the annulus from control and surgical disc specimens using electron microscopy and specialized fixation that visualizes proteoglycans. SUMMARY OF THE BACKGROUND DATA: The ultrastructural features of disc cells and the disc matrix have received little attention, as compared with the literature on age- and disease-related changes in bone and cartilage. METHODS: Ultrastructural studies investigated disc tissue obtained from control and surgical disc specimens using transmission electron microscopy. Specialized fixation with ruthenium red was used to highlight matrix proteoglycans. RESULTS: Cellular and extracellular matrix fine structure was assessed in disc specimens from 29 control donors (newborns to 79-year-olds) and surgical disc specimens from 49 patients (16- to 77-year-olds). Control and surgical tissue showed similar ultrastructural features. Unusual matrix surrounding and encircling single cells or clusters of cells was common (48% of control and 63% of surgical specimens) and often contained fibrous long-spacing collagen (41.3% of control and 36.7% of surgical specimens). Ruthenium red greatly aided visualization of proteoglycans pooled in lacunar spaces. Variable cross-sectional diameters of collagen fibrils was present in 34% of control and 59% of surgical specimens. Regions with sparse interterritorial matrix were common. Cell morphology showed both cells with apoptotic nuclei and synthetically active cells that appeared healthy. CONCLUSIONS: Control and surgical specimens of the annulus showed similar ultrastructural features. Heterogeneity of collagen fibril diameter is an important observation because it is believed that fibril size relates to biomechanical disc function. Fibrous long-spacing collagen may reflect extracellular matrix remodeling or the presence of previous fibril depolymerization followed by repolymerization and reassociation with proteoglycans. Synthetic activity of disc cells is reflected in active rough endoplasmic reticulum, Golgi, and pools of proteoglycans in lacunar spaces and unusual extracellular matrix components that encircle cells and cell clusters. Such components may influence biomechanical quality. Departures from normal extracellular matrix organization of the aging or degenerating disc undoubtedly contribute to decreased biomechanical function of the annulus because they disrupt the normal annulus architecture. This study underscores the need for a fuller understanding of the dynamic relation between disc cells and the surrounding extracellular matrix, which they continually produce and remodel.

Adolescent↗
PubMed1997

Apoptosis of mononuclear cell infiltrates in cardiac allograft biopsy specimens questions studies of biopsy-cultured cells.

During acute rejection, CD4 and CD8 T cells infiltrate the myocardium and cause myocyte death and dropout. CD4 and CD8 cells use a number of cytotoxic mechanisms, including fas-fas ligand interactions, which lead to apoptotic death. Since fas is expressed on myocytes, we investigated endomyocardial biopsy specimens from cardiac transplant patients to determine whether apoptosis is one of the mechanisms of cell death in acute rejection. Serial sections of individual endomyocardial biopsy specimens from patients histologically diagnosed as having grade 3A rejection (n=22 biopsy specimens), biopsy specimens showing a typical "Quilty effect" (n=10), and specimens with concurrent grade 3A rejection and the Quilty effect (n=6) were evaluated using the C-terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) technique for frequency of apoptosis in myocytes and mononuclear cell infiltrates. None of the examined sections showed detectable evidence of apoptotic myocytes, even within regions clearly showing myocyte damage. Of interest was our consistent finding that 85-98% of mononuclear cell infiltrates within biopsy specimens scored as having grade 3A rejection had undergone apoptosis. In marked contrast, 9 of the 10 specimens with Quilty lesions showed <5% apoptotic mononuclear cells in the endomyocardial infiltrates. Of further interest was our finding of 85-98% apoptotic mononuclear cell infiltrates within Quilty lesions associated with biopsy specimens scored as having grade 3A rejection. The frequency of apoptotic cells determined by the TUNEL technique was confirmed by histological examination of the morphology of the cells and with a technique that involves detection of c-jun. These results prompt a note of caution in the interpretation of data on the phenotype, cytokine profile, Vbeta T cell receptor repertoire, and donor specificity of mononuclear cells cultured and propagated from such cardiac biopsy specimens. The possible reasons for apoptosis of graft-infiltrating mononuclear cells are discussed.

Adult↗
PubMed2002

Confirmation of the Department of Transportation criteria for a substituted urine specimen.

The purpose of this study was to determine whether people could naturally produce urine sufficiently dilute to meet the federal criteria for a "substituted" specimen. The United States Department of Transportation Regulations (49 Code of Federal Regulations Part 40) defines a urine specimen as substituted if it has a creatinine concentration of < or = 5 mg/dL and a specific gravity of < or = 1.001 or > or = 1.020. These criteria have been criticized based on the contention that an insufficient number of specimens had been tested from the same urine sample for both creatinine and specific gravity measurements. We reviewed the results of 803,130 random urine specimens measured for creatinine and/or specific gravity in a hospital-based laboratory. In this database, 13,467 urine specimens had both creatinine and specific gravity measurements. None of these 13,467 paired urine specimens met the lower limit of specific gravity (< or = 1.001) and creatinine (< or = 5 mg/dL) criteria for a Department of Transportation substituted specimen. We also examined the medical records of those patients meeting even one of the two criteria; creatinine concentration < or = 5 mg/dL or specific gravity < or = 1.001. These patients were neonatal, moribund, or so severely ill that essentially none could have been among the working population. These data in patients with various pathologic states support our belief that normal individuals do not produce urine dilute enough to meet the lower limit of the specific gravity (< or = 1.001) and creatinine (< or = 5 mg/dL) required for meeting substituted specimen criteria. Eleven patients met the criteria for a substituted specimen, with elevated specific gravity of > or = 1.020 and creatinine concentration of < or = 5 mg/dL; however, these patients were seriously ill or terminally ill.

Adolescent↗