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PubMed2000

The bone marrow in Hodgkin's disease--a two year study.

A total of forty bone marrow trephine biopsies and aspirates were studied from thirty five patients suffering from Hodgkin's disease during the two year period 1994 and 1995. Of these twenty five were at the time of diagnosis of the disease and fifteen after treatment. The biopsies were studied for incidence of involvement as well as associated findings in both the positive and negative biopsies. A comparison of the trephine biopsy with marrow aspirate with respect to yield of positivity was made. Five patients (20%) at the time of diagnosis and two (13.33%) after treatment showed involvement of the marrow. None of the seven corresponding aspirates were positive for involvement showing that biopsies were superior to aspirates in detecting marrow infiltration in Hodgkin's disease. Suppression of the marrow, fibrosis and lymphocytic aggregates were the other findings in positive biopsies. Eosinophilia and myelosuppression were notable changes in the negative biopsies. One biopsy also showed granulomas. The probable significance of these findings are also discussed.

Adult↗
PubMed2003

Histomorphometric study of megakaryocytes in bone marrow in selected myeloproliferative and lymphoproliferative diseases.

The aim of the study was an estimation of the histomorphometry of megakaryocytes (MK) in bone marrow in selected myeloproliferative and lymphoproliferative diseases. Bone marrow specimens were obtained by trephine biopsies from 41 patients with polycythaemia rubra vera (PV), idiopathic myelofibrosis (MF), chronic lymphocytic leukaemia (CLL), hairy cell leukaemia (HCL) and diffuse large B-cell lymphoma (L). Morphometric evaluation was performed using a standard program set MicroImage (OLYMPUS). The greatest number of typical nucleated MK, "naked" nuclei, anucleated cytoplasmic fragments and the largest area were found in PV. The circular deviation factor of MK and their nuclei increased in all cases. The greatest number of clusters was observed in PV and HCL. A significant increase in the number of dysplastic and "naked" nuclei of MK was noted in all selected haematological diseases. The presence of neoplastic cells in bone marrow increased the morphological changes in MK. Quantitative and morphometrical significant differentiation of MK in separate microscopic field in the same slides confirms the necessity of performing trephine biopsies in each patient with haematological disorders.

Bone Marrow Cells↗
PubMed1992

Atraumatic surgical technique and implant bed preparation.

The issues of bone necrosis and implant bed congruency are both central to the success or failure of endosseous dental implants to achieve osseointegration. Use of internally irrigated drilling instruments has been postulated to minimize bone necrosis. The ability of the cutting instruments to produce a smooth, congruent implant bed and retain fine bone structures is also critical to achieving primary integration. In the experiment conducted, the use of internally cooled instruments reduced the likelihood of thermal bone damage, particularly when trephine mills were used. Trephine mills were able to retain the fine bone structures of the walls of the implant bed site. No visible degradation occurred from multiple uses of the instruments.

Animals↗
PubMed2003

[Hypopituitarism and hematological abnormalities mimicking myelodysplastic syndrome. Report of four cases].

Insufficiency of the pituitary gland and hematological abnormalities may coexist in the context of two syndromes. In the course of some hematopoietic neoplasms, particularly acute leukemias, the pituitary insufficiency may be caused by destruction of the gland either by direct neoplastic infiltration or occlusion of vessels. Alternatively, thy pituitary dysfunction may be associated with but not caused by hematological abnormalities, usually mild peripheral cytopenias. We present four cases of the latter type (1. M/33, pituitary tumor, hypogonadism, hyperprolactinemia, anemia, mild leukopenia with leukocytosis, 2. F/54, pituitary tumor, hyperprolactinemia, thyreotropic and corticotropic insufficiency, anemia, thrombocytopenia, mild neutropenia, 3. F/27, pituitary tumor, diabetes insipidus, hypogonadism, sideropenic anemia, leukopenia, thrombocytopenia, 4. M/24, primary multihormonal insufficiency of the anterior portion of the pituitary gland, neutropenia, microcytosis). Trephine and aspiration bone marrow biopsies revealed topographic and cytological abnormalities partially resembling these found in myelodysplastic syndromes (MDS). Bone marrow cellularity varied markedly between and within the cases, and in three patients abnormal aplastic areas were found. The percentage of hematopoietic stem cells (CD34+) was low in three cases and normal in one case. Pituitary dysfunction may be associated with hematological abnormalities simulating MDS, but showing different, less aggressive clinical course. The proliferative potential of hematopoietic cells is low, the peripheral blood abnormalities are stable, and no patient developed acute leukemia. Detailed bone marrow examination, including the trephine bone marrow biopsy, is useful in differentiation with true MDS, which was also reported in the literature in the patients with pituitary insufficiency.

Adult↗
PubMed1992

Chronic frontal sinusitis in dairy cattle: 12 cases (1978-1989).

Chronic frontal sinusitis in 12 dairy cattle most often was associated with a history of dehorning, in which the sinus was entered (67%), or with respiratory tract disease (25%). The most common organisms isolated were Actinomyces pyogenes and Pasteurella multocida. Signs of infection did not develop for months in some cattle and were often intermittent. The most common clinical signs included anorexia, lethargy, fever, frontal bone distortion, exophthalmos, abnormal posture, nasal discharge, and neurologic abnormalities. Treatment consisted of trephination at 2 sites, drainage and lavage of the sinus cavity, and administration of antibiotics and analgesics. Eight cattle responded well to treatment and were discharged, but 4 others had signs of CNS involvement and died or were euthanatized. Trephination of the frontal sinus cavity at carefully chosen sites and antibiotic treatment are indicated when sinusitis is suspected. Drainage of the sinus cavity is imperative to avoid extension of the infection into the CNS.

Animals↗
PubMed2004

[Evaluation of bone marrow biopsy and smear examinations in differential diagnosis for patients with pancytopenia by simultaneously compartive study].

To simultaneously compare and evaluate the examinations of bone marrow smear and trephine biopsy in differential diagnosis and therapeutical effect of pancytopenia patients, the differences between bone marrow smear and trephine biopsy in degree of cellularity, misdiagnosis rate and therapeutical effect for 71 patients with pancytopenia were analyzed. The results showed that the degree of cellularity in bone marrow biopsy for cytologic morphology was higher than that from the smear, but misdiagnosis rate in the biopsy was lower than that in the smear. In conclusion, bone marrow biopsy is necessary to the differential diagnosis and more valuable for evaluation of therapeutical effect and prognosis of pancytopenia patients.

Adolescent↗
PubMed2004

Chronic myeloproliferative diseases on a pathologist's desk--a dilemma of distinct entities versus a clinico-pathologic continuum. A descriptive study based on a material from the Polish population.

Chronic myeloproliferative disorders (CMPD) are traditionally diagnosed using criteria based on clinical parameters. A framework for an alternative, trephine bone marrow histology-based approach, was provided by the Hanover group of hematopathologist (the "Hanover classification"). The present study describes a single institution experience with the Philadelphia-BCR/ABL negative CMPD diagnosed on the basis of the histopathology of bone marrow in the three consecutive years (2000 - 2002). Among 246 cases of CMPD (M:F=1:1.6), there were 75 cases of idiopathic myelofibrosis (IMF), 45 of polycythemia vera (PV), 93 of essential thrombocythemia (ET), and 33 cases that were unclassifiable on the basis of morphology (CMPD-U). The clinical profiles of the IMF, PV and ET group emerging from the histological examination correlated with the expected clinical features of these diseases. The ET patients were the youngest (median 51 years) compared to PV (59.5 years), IMF (63.9), and CMPD-U (54.7). In 158 cases (74.3%), the biopsy corroborated the preliminary clinical diagnosis of CMPD, and in the half of these cases it refined the clinical diagnosis of suspected unspecified CMPD placing the disease in a particular specific category (ET, IMF or PV). In the remaining cases the biopsy was done due to an abnormality of unknown origin (usually an accidentally discovered thrombocytosis) or the clinical picture suggesting a disease other than CMPD (11.7%). Some cases of CMPD presented with atypical histological features, such as slight megakaryocytic dysplasia in ET (not justifying the diagnosis of IMF), raising the issue of the subjectivity of histological diagnosis. The trephine bone marrow biopsy provides a useful tool for the diagnosis of CMPD, particularly in the early IMF that may present with a clinical picture undistinguishable from ET, but which carries poorer prognosis and requires more vigorous treatment. A special attention should be paid to the CMPD-U group. Its current nosological status (early phases of IMF/ET/PV or distinct entity or entities?) is still unclear and requires further research.

Adult↗
PubMed1992

Axial length in keratoconus.

Axial length is a major determinant of ocular refractive power that has not been well established for keratoconus eyes. The purpose of this study was to establish the mean and range of axial length among both keratoconus eyes with no previous surgery and postkeratoplasty keratoconus eyes, and to determine if there is a significant reduction of axial length following variations in surgical techniques in penetrating keratoplasty. The axial length of 157 keratoconus eyes with no previous surgery was measured using applanation ultrasonography. The mean axial length measurement was 24.39 (+/- 1.13 mm), with a range of 21.82-28.69 mm. The axial length of 66 postkeratoplasty keratoconus eyes was similarly measured. The mean axial length measurement was 24.10 (+/- 1.22 mm), with a range of 21.83-26.87 mm. These values are not significantly different from the axial length mean and range found among emmetropic eyes. A significant shortening of the axial length (F = 5.2, p = 0.04) was obtained in the postoperative penetrating keratoplasty eye if the donor trephine was 0.3 mm smaller in diameter than the recipient trephine. The axial length of individual keratoconus eyes is a major factor in determining postoperative refractive error. It therefore becomes important when considering variations in surgical procedures to reduce postoperative myopia.

Analysis of Variance↗
PubMed2005

[Proliferation of corneal epithelium and apoptosis of keratocytes in the rabbit cornea after treatment with 20% ethanol].

OBJECTIVE: To study the proliferation activity of corneal epithelial cells and the apoptosis of keratocytes in the rabbit cornea after treatment with 20% ethanol. The results were compared to the cornea treated with mechanical scraping of the epithelial cells. METHODS: The experimental group consisted of 42 rabbits. One of the two corneas of each rabbit was incised by 8 mm epithelial trephine using in LASEK and was exposed to 20% ethanol (in distilled water) in the trephine for 40 seconds. In the other eye, the corneal epithelium in the central area was mechanically scraped. The rabbits in the experimental group were randomly divided into seven sub-groups. Each sub-group had six rabbits and the rabbits were killed at 0, 4 hours, 1, 3, 5, 8 and 30 days after the surgery. Three rabbits without any treatment were used as blank controls. Immunohistochemical staining (Ki-67 antigen) was performed to detect the proliferation of corneal epithelial cells. Apoptotic cells were detected by TUNEL assay. Number of keratocytes in the central anterior stroma of cornea was determined by counting the total number of cells under 400 x magnification field in hematoxylin-eosin-stained corneal sections. RESULTS: In the ethanol-treated eyes, the number of Ki-67 positive cells peaked 5 days after the treatment in the central corneal epithelium and 1 day after the treatment in the peripheral corneal epithelium. TUNEL-positive cells were detected in the anterior central stromal keratocytes under the epithelial incisions and the number of TUNEL-positive cells reached a peak 4 hours after the treatment. There was no statistically significant difference in the number of central anterior stromal keratocytes between the ethanol-treated group and the controls (P = 0.68). In the mechanical scraping group, the number of Ki-67 positive cells in the peripheral corneal epithelium peaked 3 days after the treatment. The number of Ki-67 positive cells in the peripheral corneal epithelium of the scraping group was greater than that of the ethanol-treated group. TUNEL-positive cells were detected in the anterior central stromal keratocytes and reached a peak 4 hours after the scraping. The number of central anterior stromal keratocytes was decreased maximally 1 day after the scraping (P < 0.01). CONCLUSIONS: The cornea injury caused by treatment with 20% ethanol for 40 seconds is milder than that caused by mechanical scraping. The wound-healing process in the ethanol-treated cornea is faster than that of the cornea treated with scraping. Corneal epithelium treated with 20% ethanol for 40 seconds can protect the stromal keratocytes.

Animals↗
PubMed2005

Comparative study of myelodysplastic syndromes and normal bone marrow biopsies with conventional staining and immunocytochemistry.

OBJECTIVE: To study the histomorphometric features of megakaryocytic elements in bone marrow trephine biopsies of various subtypes of myelodysplastic syndrome (MDS). STUDY DESIGN: Comparative image morphometry using hematoxylin-eosin-stained and CD 61-stained trephine biopsies was carried out on 40 cases of MDS and 10 normal subjects to analyze the megakaryocytes objectively. The various variables analyzed were number of megakaryocytes and micromegakaryocytes, area, perimeter and diameter of the megakaryocytic elements. RESULTS: The mean number of megakaryocytes was lower in cases of MDS as compared to the normals in all except for a single case of hypoplastic MDS, in which the megakaryocytes were more abundant (3.6 per high-power field [hpf]). No micromegakaryocytes were observed in the 2 cases of chronic myelomonocytic leukemia. The mean area, perimeter and diameter of megakaryocytes decreased significantly on immunostaining with CD 61. CONCLUSION: The mean number of megakaryocytes per hpf was lower in the cases of MDS as compared to normal cases on hematoxylin-eosin. However, on CD 61 staining the number of megakaryocytes per hpf increased in cases of MDS. Micromegakaryocytes were seen in scanty numbers in the normals but increased in MDS cases and increased significantly on CD 61 immunostaining. The mean area, perimeter and diameter of megakaryocytes decreased significantly on immunostaining with CD 61, indicating the increased numbers of micromegakaryocytes in MDS. Hence, immunostaining is an efficient method of detecting increased numbers of megakaryocytes and micromegakaryocytes that would ordinarily be missed by using routine hematoxylin-eosin staining.

Anemia, Aplastic↗
PubMed2003

Bone marrow cryptococcosis: a case report.

A 35-year-old male presented with fever and bilateral cervical and axillary lymphadenopathy. Peripheral blood film examination revealed thrombocytopaenia. Bone marrow aspiration and trephine biopsy, done for evaluation of thrombocytopaenia and pyrexia showed presence of ill-defined granulomas along with cryptococcal yeast forms. Fine needle aspiration of lymph nodes, cerebrospinal fluid and sputum analyses also showed cryptococci. ELISA for Human Immunodeficiency Virus (HIV) antigen was positive. Granulomas, when found in bone marrow aspiration smears and trephine biopsy, are a valuable histological clue to an opportunistic infection. Disseminated fungal infection such as cryptococcosis should raise the possibility of immunosuppression, especially Acquired Immunodeficiency Syndrome. Bone marrow examination is a useful method of diagnosing opportunistic fungal and mycobacterial infections in patients with fever, anaemia or thrombocytopaenia and underlying HIV infection.

AIDS-Related Opportunistic Infections↗
PubMed2005

Grading of marrow fibrosis in chronic myeloid leukemia--a comprehensive approach.

In the course of Chronic myeloid leukemia (CML), appearance of increased number of blasts may herald evolution of accelerated phase as well as onset of marrow fibrosis (MF) thereby necessitating the need to perform trephine biopsy for correct diagnosis and appropriate treatment. In the existing grading systems of MF, a comprehensive view has not been taken of the variability of density and area occupied by reticulin and collagen fibres. To overcome this shortcoming, we quantitated the reticulin and collagen content of marrow, its pattern of distribution and percentage area occupied by each type of fibres in every individual case. We performed 50 bone marrow (BM) trephine biopsies in patients of CML in order to assess the incidence and degree of MF. Various grades of MF were correlated with peripheral smear including blast count, bone marrow aspirate and LAP score of the case. A positive correlation was found between increasing grades of MF and number of megakaryocytes in the BM.

Adult↗
PubMed1990

Effects of fluorouracil and fluorouridine on protein synthesis in rabbit retina.

5-Fluorouracil (5-FU) and its active metabolite 5-fluorouridine (FUR) are currently being evaluated for the treatment of proliferative vitreoretinopathy and the control of scarring after glaucoma filtering procedures. To test for retinal toxicity, the authors examined the effect of intravitreal injections of 5-FU and FUR on protein synthesis in rabbit retinal photoreceptors and ganglion cells. In addition, the toxic effect of subconjunctival 5-FU injections, after a trephine filtering procedure, on ganglion cell protein synthesis was examined. Albino rabbit eyes were given either unilateral intravitreal injections of 1 mg of 5-FU, 2.5 mg of 5-FU, or 0.1 mg of FUR, or subconjunctival injections of 3 mg of 5-FU twice daily after a trephine procedure. Quantitative autoradiography was used to study ganglion cells and photoreceptor outer segment renewal, and scintillation counting was used to quantify newly synthesized protein transported axonally from ganglion cell bodies to the superior colliculus (SC). Marked reduction of labeled protein reaching the SC was noted after either intravitreal 0.1 mg of FUR (41% inhibition after a single injection and 53% after two injections) or 2.5 mg of 5-FU (41% after one injection and 26% after two injections). This reduction was still present after 8 days in eyes receiving 0.1 mg of FUR (32%) and 2.5 mg of 5-FU (22%). Quantitative autoradiography of retinal photoreceptors and ganglion cells corroborated these data, demonstrating inhibition of outer segment renewal after one or two injections of either 0.1 mg of FUR or 2.5 mg of 5-FU. This inhibitory effect was statistically significant using the paired t-test for both drugs. No mean inhibition was observed after intravitreal 1 mg of 5-FU injections or after subconjunctival injections of 5-FU.

Animals↗
PubMed2006

Decrease of cone opsin mRNA in experimental ocular hypertension.

PURPOSE: This study was designed to test the hypothesis that photoreceptors are adversely affected in glaucoma. As a measure of this effect, we examined the levels of rod opsin, and red/green and blue cone opsin mRNAs in monkeys with experimental ocular hypertension and glaucoma and in human eyes from donors with diagnosed glaucoma. METHODS: Experimental ocular hypertension was induced in one eye of 19 cynomolgous and 2 rhesus monkeys by laser ablation of the trabecular meshwork. In 15 monkeys, the elevated IOP was reduced by trabeculectomy. When the animals had experienced prolonged elevations of IOP (128 to 260 days), they were killed and the eyes enucleated. Fresh retinal tissue from the macula, inferotemporal retina (mid-peripheral), and far peripheral regions were harvested from some animals using a 3 mm trephine. The remaining retinas from these monkeys, and whole retinas from other animals were fixed. RNA isolated from each trephined sample was used for RNase Protection Analysis or real time PCR analysis to quantify opsin mRNA levels from different photoreceptor cell types. Fixed tissue was used for in situ hybridization studies. Human donor eyes (7 glaucoma and 4 control) were obtained from eye banks. All human specimens were used for in situ hybridization studies. RESULTS: Quantitative mRNA analysis and in situ hybridization studies both showed a reduction in the expression of red/green and blue cone opsin mRNAs in 6 monkey eyes with chronic ocular hypertension, relative to the contralateral eye. No loss of rod opsin mRNA was observed. The principal reduction occurred in cells of the mid-peripheral retina, a region of retina that often shows early and progressive damage in humans with glaucoma. In monkeys with ocular hypertension followed by trabeculectomy, there was a similar decrease in cone opsin mRNAs, but only in six out of fifteen (40%) of the monkeys. The decrease in these animals was correlated with a significantly elevated IOP at some time during the 2 weeks prior to euthanization and not with the extent of glaucomatous damage. Of the 7 human eyes with diagnosed glaucoma that were examined, 5 showed a decrease of cone opsin mRNA in the mid-peripheral retina, whereas none of the 4 normal eyes examined showed a decrease. CONCLUSIONS: Ocular hypertension leading to glaucoma also affects the outer retina, particularly the cone photoreceptors. We speculate that these cells become stressed leading to a disruption in the expression of normal genes, such as that encoding opsin. There is some evidence that this effect is reversible, when IOP levels are reduced.

Aged↗
PubMed1990

[Mathematical model of the rotation of cornea].

The aim of our study is to informatise the procedure, ie, design the computer system and software necessary to automatically define the parameters of our problem. To achieve this, we have used an image analyser which permits us to acquire and digitalise a photograph of the lesioned cornea. Digitalisation of the image allows us to determine the co-ordinates (x, y) of the points which lie on the lesion periphery as well as the co-ordinates of the corneal centre, ie, geometric centre of the cornea. One calculates the centre of trephination and the optimal diameter of trephination as a function of a point situated on the lesion edge.

Cornea↗
PubMed1989

Shadow photogrammetric apparatus for the quantitative evaluation of corneal buttons.

We have developed a technique for the accurate, quantitative, geometric evaluation of trephined and punched corneal buttons. A magnified shadow of the frontal and edge views of a corneal button mounted on the rotary stage of a modified optical comparator is projected onto the screen of the comparator and photographed. This process takes approximately three minutes. The diameters and edge profile at any meridian photographed can subsequently be analyzed from the film. The precision in measuring the diameters of well cut corneal buttons is +/- 23 microns, and in measuring the angle of the edge profile is +/- 1 degree. Statistical analysis of inter observer variability indicated excellent reproducibility of measurements. Shadow photogrammetry offers a standardized, accurate, and reproducible method for analysis of corneal trephination.

Calibration↗
PubMed1989

Excimer laser keratoplasty. Part 1: Basic concepts.

A commercially available ophthalmic excimer laser was used with a new "open mask system" to perform noncontact and nonthermal excimer laser keratoplasty in 20 human and 40 pig cadaver eyes. Circular penetrating corneal trephinations and corneal grafts were performed with the excimer laser set at 193 nm. Light microscopy and scanning and transmission electron microscopy of the human and pig eyes demonstrated the high quality of excimer laser trephination (smooth wound margins that were approximately parallel to the optical axis of the eye), and the superior wound configuration and geometry.

Animals↗
PubMed1989

Investigation into the principal determinants of effective captive bolt stunning of sheep.

In order to identify the physical component of captive bolt stunning responsible for abolishing visual evoked responses, experimental forms of captive bolt stunning were carried out on anaesthetised sheep. Supporting the captive bolt pistol away from the skull to permit limited penetration of the brain was found to be as effective as conventional shooting methods at abolishing visual evoked responses (responses were lost in all animals). Whereas, manual insertion of the bolt through a trephined hole or shooting through a trephined hole was significantly less effective (respectively, one of eight and four of eight animals lost responses). It is concluded that the impact of the bolt with the cranium is the principal determinant of effective stunning, rather than the penetration of the bolt into the brain tissues.

Animals↗