Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Trephining”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,207 records · Page 67Linked to original sources
PubMed2000

[Diagnostic importance of flow cytometry in staging malignant lymphoma].

Bone marrow biopsy plays an important role in the clinical diagnosis of malignant lymphoma. Further diagnostic methods need to be established to increase accuracy in the light of advances over recent years in the immunophenotypical characterization of discrete lymphatic bone marrow lesions and the continuing difficulty in classifying them. This study compared the diagnostic value of flow cytometry to that of conventional bone marrow biopsy in 156 patients with 191 marrow biopsy specimens or bone marrow aspirates. The most important findings were that up to one-third of lymphomas could not be diagnosed by flow cytometry, and that the degree of infiltration was estimated as less than two-thirds. However, flow cytometric results were more satisfactory in acute lymphoblastic leukemia, lymphoblastic lymphoma, hairy cell leukemia, and chronic lymphocytic leukemia. In summary, flow cytometry has a complementary role in the staging of lymphoma but cannot fully replace conventional trephine biopsy.

Biopsy↗
PubMed2000

[Histologic and hematological findings in CML. A comparative immunohistochemical-morphometric and clinical study on bone marrow biopsies from 604 patients derived from two institutes of pathology (Cologne/Freiburg)].

An immunohistochemical and morphometric study was performed on bone marrow biopsies in 604 patients with chronic myelogenous leukemia (CML) to compare morphological and clinical features and to evaluate effects of interferon (IFN) and chemotherapy. Following morphometry significant correlations were calculated between number of CD61(+) megakaryocytes, including their precursors with fiber density. This finding is in line with the close functional relationship between megakaryopoiesis and fibroblasts regarding the complex pathomechanism of myelofibrosis. The latter was observed in about 28% of patients already at diagnosis. In a similar way, the frequency of CD68(+) macrophages was correlated with the amount of Ret40f(+) nucleated erythroid precursors, implicating an involvement of this cell lineage in iron turnover, hemoglobin synthesis, and degradation of the expelled nuclei from normoblasts. The (alpha-D-galactosyl residue-expressing) Pseudo-Gaucher cells were detectable in 30% of pretreatment specimens. Moreover, significant associations were calculable between reduction in erythropoiesis or increase in fibers with clinical features such as hemoglobin level, percentages of myelo- and erythroblasts in the peripheral blood, and spleen size. These variables are in keeping with more advanced stages of CML. Based on our morphometric evaluations, a classification into three different histological subgroups: granulocytic, megakaryocytic, and myelofibrotic was carried out. This simplified staging system was correlated with corresponding sets of hematological data. Sequential biopsies in 173 patients with monotherapy by IFN, hydroxyurea (HU), or busulfan (BU) revealed a fibrogenic effect of IFN in contrast to a fiber-reducing property of HU. The dynamics of myelofibrosis and changes of major cell lineages during treatment were readily demonstrable by calculating corresponding indices. These included the ratios between quantitative differences of corresponding variables at repeated examinations and time. Thus, in patients with complete hematological remission following IFN administration, regeneration of erythropoiesis was found to be accompanied by an increase in the total number of CD68(+) macrophages, including activated subpopulations. Histological subgroups showed a transition from a (nonfibrotic) granulocytic and megakaryocyte pattern to the myelofibrotic subtype in about 40% of patients. This change was opposed to a numerical reduction in the myelofibrotic subtype which occurred in 17 patients (36%), but predominantly in those under HU therapy. In conclusion, the striking heterogeneity of bone marrow features in CML warrants a careful morphological evaluation of trephine biopsies and appropriate means of processing to achieve relevant correlations with clinical data and, thus, allows a more elaborate insight into the dynamics of the disease process.

Biopsy↗
PubMed1995

[Differential "lymphoid cell infiltrates" diagnosis in bone marrow].

The purpose of this study was to provide criteria for the differentiation of reactive lymphoid hyperplasia (RLH) and focal involvement of the bone marrow by malignant lymphoma (ML). Using trephine bone-marrow biopsy specimens embedded in paraffin wax and unequivocally established samples with ML for comparison, all patients with questionable lymphoid or lymphohistiocytic marrow aggregates were re-examined, together with obviously reactive lesions. Following this procedure, a number of characteristics were found that differed in validity with regard to diagnosis. In addition to cytology, which is preferably assessed in Giemsa-stained specimens and evaluated by the Kiel classification, histotopography, fiber content, and immunohistochemical reactions are the most valuable tools for differential diagnosis. RLH is consistent with a central-perivascular localization, a distinctive border and the presence of germinal centers, no or only minimal reticulin fibrosis and a polyclonal reaction pattern with a mixed population of B- and T-lymphocytes, following staining with appropriate antibodies. In uncertain cases (i.e., extensive lymphoproliferations in HIV-myelopathy) the results of immunohistochemical staining are of definite importance for the diagnostic evaluation of these lesions.

Biopsy↗
PubMed2004

[Functional results after autologous rotational keratoplasty. A retrospective study].

BACKGROUND: Autologous rotational keratoplasty is a therapeutic option in patients with central corneal scars. Its advantage compared to allogeneic procedures is the absence of immunologic destruction. In this retrospective analysis, long-term results are presented. PATIENTS: Since 1988, autologous rotational keratoplasty was performed in 19 patients. The trephine size varied between 7.0 mm and 9.0 mm. Mean follow-up was 7.1+/-4.6 years. RESULTS: In 16 of the patients, the graft center remained clear during the entire follow-up period. Visual acuity improved from 0.25+/-0.16 preoperatively to 0.34+/-0.27 postoperatively with spectacles and to 0.43+/-0.3 with contact lenses. The mean postoperative astigmatism was 6.41+/-3.87 dpt with irregular components in six patients. CONCLUSION: Only a few postoperative graft complications were observed. Especially in patients with a markedly elevated risk for immune reactions (e.g., small infants), autologous rotational keratoplasty is a safe alternative to allogenic procedures.

Adult↗
PubMed2003

[Techniques for posterior lamellar keratoplasty through a scleral incision].

PURPOSE: To describe several techniques for posterior lamellar keratoplasty through a scleral incision, for management of corneal endothelial disorders like pseudophacic bullous keratopathy and Fuchs' endothelial dystrophy, and to report the mid-term clinical results. METHODS: Three techniques have been developed to perform a posterior lamellar keratoplasty procedure through a scleral incision, i.e. to replace the posterior corneal layers while leaving the anterior corneal surface intact and without the use of corneal sutures. In the first technique, a 9.0 mm scleral incision is made to accommodate an intracorneal trephine and spoon-shaped glide to insert a 7.5 mm donor posterior lamellar disc into the anterior chamber. In the second technique, the procedure is performed through a 5.0 mm scleral tunnel incision using microscissors and by folding a 8.5 mm donor posterior disc prior to insertion. In the third technique, a 4.0 mm tunnel incision is made to perform a descemetorhexis in the host cornea, i.e. Descemet's membrane is selectively excised from the recipient eye, and a 9.0 mm donor Descemet's membrane is inserted. In eyes with a minimal postoperative follow-up of 3-5 years ( n=16), we documented the best spectacle corrected visual acuity (BSCVA), keratometry readings, endothelial cell counts, and clinical events. RESULTS: In all cases, the graft adhered to the recipient posterior cornea without suture fixation. In patients without concomitant ocular disease, BSCVA was 0.7-1.0 in all eyes. The astigmatism averaged 2.1+/-0.7 D, endothelial cell counts averaged 2126+/-529 cells/mm(2) at 6 months, 1839+/-473 cells/mm(2) at 12 months, 1418+/-434 cells/mm(2) at 24 months, and 1137+/-420 cells/mm(2) at 36 months. In two patients, an irido-corneal adhesiolysis was performed within days after the procedure. In one patient, residual visco-elastic adherence was present at the donor-to-recipient interface, and a penetrating keratoplasty was performed 1 month postoperation. One patient developed significant interface haze, requiring a penetrating keratoplasty 13 months after the first surgery. CONCLUSION: Posterior lamellar keratoplasty can be an effective surgical technique to manage corneal endothelial disorders. An improved visual acuity can be obtained within the first weeks after surgery, and the visual perfomance of the graft is stable up to 5 years postoperation.

Corneal Diseases↗
PubMed1997

[Obtaining donor corneas without eyeball removal].

The goal of the present study was to compare the quality of 7-mm corneal buttons taken directly from donor eyes with commonly obtained transplants. Seven-mm porcine corneal specimens and 16-mm cornoscleral specimens were immersed for 3 and 7 days in Optisol culture medium. After 3 days, ultrasonic pachometry revealed a decline to 73% of the original thickness in the 7-mm and to 83% in the 16-mm specimens. After 8 days, the thickness in both groups had returned to 91% of the original values. Light microscopy revealed a homogeneous endothelial layer in both groups. Staining with 0.25% Trypan blue revealed only a few dead cells. The 7-mm specimens exhibited fewer wrinkles in Descemet's membrane than the 16-mm specimens. Scanning electron microscopy of human 7-mm corneal specimens, some obtained directly from donor eyes and stored in Optisol and some trephined from 16-mm corneoscleral specimens after immersion, detected uniformly smooth cutting edges in both groups. Even the endothelia displayed no marked differences. Our results show that the quality of donor specimens removed at the desired size in situ and stored in Optisol equals that of commonly obtained specimens. Further investigations must show the feasibility of this procedure in practice.

Animals↗
PubMed1997

[Homologous central limbo-keratoplasty in limbus stem cell damage. Retrospective study of 3 years' experience].

BACKGROUND: Problems with epithelial healing are the main cause of corneal graft failure in patients with limbal stem cell deficiency. This post-operative complication cannot be eliminated by conventional penetrating keratoplasty alone, but only by additional limbal grafting, which is, however, highly immunogenic. We report here our 3 years' experience with a new surgical procedure which we developed called homologous central limbokeratoplasty. PATIENTS AND METHODS: We have performed 52 homologous central limbo-keratoplasties in patients with limbal stem cell deficiency since February 1993. We report here the results of the first 18 transplantations with the longest follow-up periods (mean 22 months). The unmatched donor cornea was trephined in a way such that 40% of its circumference contained limbus. These grafts were then sutured centrally into the host cornea. Systemic cyclosporin A (CSA) was administered for at least 1 year after all transplantations. RESULTS: Fourteen of the 18 grafts failed during the follow-up period. The reasons for graft failure were severe surface disorders (7), severe surface disorders in combination with endothelial immune reactions (5) and endothelial immune reactions alone (2). The four patients with centrally clear grafts no longer receive systemic CSA with follow-up periods between 20 and 30 months. CONCLUSIONS: Central limbo-keratoplasty is a very promising procedure. However, the average results are not yet satisfying, because the majority of limbal stem cells undergo rejection within 2 years. Improved results will be achievable in the future by using well-matched instead of non-matched transplants and by further improving immune modulation beyond the effectiveness of current CSA treatment.

Adolescent↗
PubMed2001

[Morphological results after eccentric perforating keratoplasty].

OBJECTIVE: Due to unfavourable optical and immunological conditions, an eccentric position of the corneal transplant is limited to curative or tectonic indications. The purpose of this study was to assess the morphological results of eccentric homologous penetrating keratoplasty (PK) with respect to diagnosis as well as position and size of the corneal graft. PATIENTS AND METHODS: In our retrospective study, 122 cases of eccentric homologous PK in 96 eyes between 01/1989 and 10/1997 were included, which in 104 patients was necessary because of a corneal ulcer (36 previous PK, 21 areactive/rheumatic, 20 herpetic, 15 bacterial, 12 other). Elective PK was performed on 6 eyes with corneal scars, 7 eyes with ectatic corneal diseases (ECT) and 5 others. Using postoperative slides the following parameters were quantified: the graft diameter (GD) and transparency, the distance of the geometric centre of the cornea from the central trephination margin (ABS) as well as from the geometric centre of the graft (decentration, DEZ). Of these, 17 grafts were classified as eccentric peripheral keratoplasty (EPK) with the optical axis through the host cornea and 67 as eccentric central keratoplasty (ECK) with the optical axis through the graft. RESULTS: The average follow-up period was 25 months. In EPK (ulcers only, 5.0 +/- 1.7 mm) the mean GD was significantly lower than in ECK (78% ulcers, 7.0 +/- 1.3 mm) (p < 0.001). The decentration of EPK (3.5 +/- 1.1 mm) was significantly higher than for ECK (1.4 +/- 0.8 mm, p < 0.001). ABS of EPK was +1.3 +/- 0.9 mm and for ECK was -2.0 +/- 1.0 mm. Of the grafts in EPK and ECK 46%/57%, respectively were crystal clear, 18%/15% respectively showed minor decompensation and 36%/28% were completely cloudy. In cases of ulcers/scars/ECT/others, 45%/75%/100%/75% were crystal clear, respectively, 18%/25%/0%/0% showed minor decompensation and 37%/0%/0%/25% were completely cloudy. With increasing stages of cloudiness, the mean graft decentration increased from 1.4 +/- 1.1 mm (crystal clear) to 1.7 +/- 1.2 mm (minor decompensation) and 2.2 +/- 1.4 mm (completely cloudy). Transplants with greater GD (p = 0.04) and ABS (p = 0.01) were significantly more often clear. Ulcers were significantly more cloudy than scars/ECT (p < 0.01). The position of the graft and its cloudiness was not significantly correlated. CONCLUSION: The diagnosis leading to eccentric PK seems to have the greatest impact on long-term graft transparency. Our results indicate that an increasing decentration of the graft is not inevitably associated with an increasing probability of clouding. A central penetrating repeat keratoplasty may be considered in the non-inflamed interval after eccentric tectonic mini-keratoplasty.

Adolescent↗
PubMed2000

A survey of contemporary management of frontal sinus disease in the United Kingdom.

Surgery for frontal sinus disease historically has required an external approach. With the advent of endoscopic sinus surgery, endoscopic treatment for various frontal sinus pathologies has been described. This survey examined how widespread the use of endoscopy in frontal surgery has become. We were interested both in the acute emergency situation and in the more chronic situations such as mucocoeles. The replies of 266 practising United Kingdom surgeons to a postal questionnaire were evaluated. While 45% of surgeons regularly practise functional endoscopic sinus surgery (FESS), approximately 25% would attempt endoscopic drainage of acute frontal sinusitis and most perform an external trephine. Most surgeons also rely on external approaches to manage mucocoeles or pyocoeles (54%), although some (39%) attempt endoscopic drainage if the cyst lies sufficiently medially. Even with recurrent or intractable disease one-third attempt endoscopic surgery. When external surgery is used in the United Kingdom, only a small number of surgeons favour obliteration.

Abscess↗
PubMed2005

Preliminary results after implantation of four AlphaCor artificial corneas.

PURPOSE: The purpose was to evaluate the validity of implantation of the artificial cornea (AlphaCor) in human corneas considered too high risk for penetrating keratoplasty with donor tissue. METHODS: Four keratoprostheses, made from poly(2-hydroxyethyl methacrylate) (PHEMA) with a porous skirt and a transparent optical part, were implanted into the cornea of four patients. Keratocytes invading the skirt provide a watertight fixation with the scarred corneal tissue. Deep to the clear optical part, the posterior corneal lamella was excised to a diameter of 3.5 mm before the device was implanted, and the anterior lamella was trephined similarly 3 months after AlphaCor implantation. RESULTS: The eyes selected to receive an artificial cornea had significant neovascularisation, and 0-3 previous failed grafts. Follow-up for 6 months revealed best visual acuity between 20/400 and 20/50. Factors limiting the visual acuity outcome were optic atrophy and age-related macular disease. One patient underwent an extracapsular cataract extraction after the device was implanted, as a senile cataract was then noted. One complication occurred, a central corneal stromal melt, which was managed by covering with a 9-mm donor lamella. CONCLUSION: The flexible device AlphaCor may provide a substitute for donor corneal tissue in desperate cases. Advantages include the simple implantation technique, which avoids trauma to the surrounding structures. Visual acuity results may be limited by pre-existing pathology, but it appears that a patient's visual potential can be achieved. Further follow-up to exclude long-term complications is required.

Adult↗
PubMed2000

Repopulation of denuded murine Descemet's membrane with life-extended murine corneal endothelial cells as a model for corneal cell transplantation.

BACKGROUND: Corneal endothelial cell transplantation has been an intriguing concept as an alternative to full-thickness penetrating keratoplasty. Using a murine corneal transplantation model, we sought to establish the optimal conditions to repopulate, ex vivo, denuded murine Descemet's membrane with life-extended cell cultures of murine corneal endothelial cells. These ex vivo repopulated corneas were used as donor corneas in a murine orthotopic corneal transplantation model to assess, in vivo, the function of the transplanted, life-extended murine corneal endothelial cells (MCEC). METHODS: Mouse corneas were surgically trephined and the native corneal endothelium was removed mechanically using a sterile cotton swab. Cultured murine corneal endothelial cells (life extended by expression of the SV40 large T antigen) were added onto the denuded Descemet's membrane and allowed to attach in culture at 37 degree C. Evidence of corneal cell attachment to Descemet's membrane was determined between 1 and 8 h by scanning and transmission electron microscopy. Donor life-extended corneal endothelial cells were labeled with a fluorescent dye to allow tracking of the donor cells following seeding onto denuded Descemet's membrane. In four independent experiments, the Descemet's repopulated corneas were placed into syngeneic mice and evaluated for corneal clarity after 6 weeks. RESULTS: We could detect attachment of the life-extended murine CEC by scanning and transmission electron microscopy to denuded Descemet's membrane. The optimal time for adherence was 2 h and these repopulated corneas were used as donors in a murine model of penetrating keratoplasty. Of 20 mice evaluated after 6 weeks, 4 displayed corneal clarity, and fluorescent evaluation demonstrated that only the donor corneal endothelial cells were present. CONCLUSIONS: This experimental protocol establishes that "life-extended" MCEC can bind to Descemet's membrane ex vivo and form a distinct monolayer. The repopulated Descemet's membrane allowed us to directly test the hypothesis that cultured life-extended corneal endothelial cells are functional when reintroduced into an in vivo milieu and provides evidence that specific corneal endothelial cell transplantation may be a viable alternative to pentrating keratoplasty.

Animals↗
PubMed2001

Testing of corneoscleral discs and their culture media of seropositive donors for hepatitis B and C virus genomes.

UNLABELLED: The prevalence of donors seropositive for hepatitis B virus (HBV) surface antigen (HBsAg) or hepatitis C virus (HCV) antibody (anti-HCV) in western countries is estimated to be 0.5%-1%. There have been only two cases, however, published so far, where hepatitis B was suspected to have been transmitted by penetrating keratoplasty [4]. Concerning HCV, no suspected transmission by keratoplasty has been reported so far. This is also true for the time before serological screening for infectious diseases became mandatory for corneal donors. In the Lions Cornea Bank North Rhine Westfalia, 4.7% (HBV) and 3.2% (HCV) respectively of the corneas of the years 1995 to 1999 were discarded due to a "non-negative serology". In about 50% of these cases the screening test (ELISA) generated no valid signal and, therefore, a "questionable positivity" was assumed. Since in Germany corneal graft shortage still is a limiting factor for penetrating keratoplasty, this study was to evaluate the detectability of HBV-DNA and HCV-RNA in the serum samples, organ culture media and corneas of donors tested seropositive for HBsAg or anti-HCV in an attempt to obtain information as to the potential infectivity of this donor material. In this study, 29 corneas of 17 donors seropositive by ELISA for HBsAg and 27 corneas of 14 donors seropositive by ELISA for anti-HCV were evaluated. The organ culture media and the sera were screened for the presence of HBV-DNA or HCV-RNA by PCR. The corneoscleral discs were divided into a central trephinate (7 mm) and the corneoscleral rim. Concerning HBV-DNA both tissues were examined separately by polymerase chain reaction (PCR). In the case of HCV-RNA, a further, more sensitive nucleotide amplification method (NAT), the transcription mediated amplification (TMA), was used to test media, central corneas and cornealscleral rims. The media were additionally tested by PCR. Viral nucleic acid was detected in the sera from 6 of 17 HBsAg positive donors and from 6 of 14 anti-HCV positive donors. Viral genomes could not be detected in the organ culture media nor in the central corneas or corneoscleral rims by PCR at a detection limit of 1000 and 100 copies/ml. Concerning HCV-RNA, two media were positive in the TMA with 50-100 copies/ml. CONCLUSION: according to our results, the risk of transmitting hepatitis B or C virus by penetrating keratoplasty appears to be low: although hepatitis C virus RNA could be detected in 2 media (from two donors) out of 27 with a low concentration of virus copies between 50-100/ml. It remains open whether such a low virus particle number may cause infection in the recipient.

Adolescent↗
PubMed2000

A novel brain trauma model in the mouse: effects of dexamethasone treatment.

We describe a novel methodological approach for inducing cold lesion in the mouse as a model of human cortical contusion trauma. To validate its reproducibility and reliability, dexamethasone (Dxm) was repeatedly applied to demonstrate possible antioedematous drug effects. Following the induction of anaesthesia with halothane, the dura was exposed via trephination. Using a micromanipulator a pre-cooled (-78 degrees C) copper cylinder, 3 mm in diameter, was pressed down to a depth of 1 mm onto the dura for 30 s under microscopic control. The body temperature was held constant at 37 degrees C throughout the procedure. Blood pressure (BP), measured by a modified photosensor-monitored tail-cuff method, and acid-base status were not significantly different when analysed before and after cold lesion and prior to sacrifice. However, there was a marginal mixed respiratory and metabolic acidosis. The antioedematous action of Dxm was studied in four standard pre-and post-treatment paradigms: 2x0.5 mg/kg (II), 2x12.5 mg/kg (III) and 4x6.25 mg/kg (IV: 3x pre-, 1x post-treatment: V: 1x pre-, 3x post-treatment). Physiological saline injections served as controls. High doses of Dxm (III-V) significantly attenuated the cold-lesion-induced loss of body mass. Dxm treatment also resulted in a reduction of brain water content (III; P<0.05), and brain swelling (IV; P<0.05) in the lesioned hemisphere, relative to controls. In conclusion, we have characterized a novel cold lesion model in the mouse to mimic traumatic brain injury and the beneficial effect of Dxm treatment on the extent of brain oedema.

Acid-Base Equilibrium↗
PubMed2004

Microvessel density, endothelial-cell proliferation and carbonic anhydrase IX expression in haematological malignancies, bone-marrow metastases and monoclonal gammopathy of undetermined significance.

The aim of the study was to compare the angiogenic status, potential qualitative differences in microvessels and carbonic anhydrase IX expression in bone-marrow (BM) metastases and different haematological tumours at time of diagnosis. The microvessel density (MVD), endothelial-cell proliferation (ECP) and carbonic anhydrase IX (CA IX) immunoreactivity were determined on 210 trephine biopsies from 57 patients with multiple myeloma (MM), 13 with acute myeloid leukaemia (AML), 48 with chronic myeloproliferative syndrome (CMPS), 26 with chronic lymphocytic leukaemia (CLL), 25 with epithelial BM metastases, 18 with monoclonal gammopathy of undetermined significance (MGUS) and from a control group composed of 23 patients without haematological neoplasm. There was an increased MVD and ECP in epithelial BM metastases, MM, AML, CMPS and in a part of CLL. While an ECP greater than 0 was detected in 72% of MM, 75% of CMPS and 92% of AML, it was invariably observed (100%) in the BM metastases. The absence of ECP together with a MVD comparable with the control group in our MGUS cases supports the view that MGUS is a pre-angiogenic condition. Qualitative differences in microvessels were associated with growth patterns in MM and CLL and were observed between the different entities of CMPS. In one-third of the epithelial BM metastases, there was a focal CA IX immunoreactivity, which was never observed in the haematological diseases.

Antigens, Neoplasm↗
PubMed2005

Quantification of clonal hematopoiesis in polycythemia vera.

Polycythemia vera (PV) is believed to represent a clonal trilineage myeloaccumulative hematopoietic disorder. This study was undertaken to estimate for the first time the proportion not only of the neoplastic clone but also of clonal and residual nonneoplastic CD34(+) progenitor cells. Chromosomal abnormalities, including trisomy 8 or 9, are phenomena associated in about 20% of PV patients. Therefore, we screened peripheral blood (PB) mononuclear cells of PV patients in the chronic phase of the disease and looked for chromosomal abnormalities performing comparative genomic hybridization. Two of the ten patients revealed cytogenetic changes, including trisomy 8 or 9. To quantify the proportion of cytogenetic abnormal cells in these patients, we applied fluorescence in situ hybridization (FISH) technique on immunomagnetically enriched cell fractions. Ninety percent of the mononuclear cells and up to 79% of PB-derived CD34(+) progenitor cells presented three signals for chromosome 8 or 9. The diagnostic value of FISH to detect trisomies in trephine biopsies was then tested in all patients under study. Although the probability to detect FISH signals in a certain section plane is reduced, constantly 10-15% of the cells revealed three signals. Concerning the CD34(+) progenitor cell pool, a distinct nonclonal population exists in these patients. Our data underline the stem cell character of PV and additionally quantify the proportion of clonal CD34(+) progenitor cells for the first time. The finding of a distinct, not aberrant, CD34(+) progenitor cell population in chronic phase PV may offer perspectives in treatment of the disease. Finally, FISH analysis of bone marrow biopsies can be helpful to consolidate diagnosis of early PV.

Adult↗
PubMed2000

Macrophages and their subpopulations following allogenic bone marrow transplantation for chronic myeloid leukaemia.

A morphometric and immunohistochemical study was performed on 354 bone marrow trephine biopsies derived from 126 patients with chronic myeloid leukaemia (CML) before and after allogeneic bone marrow transplantation (BMT). The purpose of this investigation was to evaluate the macrophage population, including several subsets and their dynamics in the posttransplant period. In addition to the total CD68+ resident (mature) macrophages the so-called activated fraction identified by its capacity to express alpha-D-galactosyl residues, the pseudo-Gaucher cells (PGCs) and the iron-laden histiocytic reticular cells were also considered. Following immuno- and lectin-histochemical staining morphometric analysis was carried out on sequential postgraft bone marrow specimens at standardized intervals. Compared to the normal bone marrow and calculated per haematopoiesis (cellularity) an overall decrease of about 40-50% in the quantity of CD68+ macrophages and the BSA-I+ subpopulation was detectable in the early posttransplant period (9-45 days after BMT). Noteworthy was the temporal recurrence of PGCs in the engrafted bone marrow, which was not associated with a clonally transformed cell population or leukaemic relapse. Reappearance of postgraft PGCs was most prominent in the first 2 months after BMT. This conspicuous feature was presumed to be functionally associated with a pronounced degradation of cell debris following pretransplant myelo-ablative therapy (scavenger macrophages). Evidence for an activation of the BSA-I+ macrophage subset was derived from the identical carbohydrate-binding capacity shown by the PGCs. In the regenerating haematopoiesis shortly after BMT a significant correlation between the number of BSA-I+ macrophages and erythroid precursor cells was determinable. This result implicates a close functional relationship between postgraft reconstitution of erythropoietic islets and centrally localized activated macrophages. In conclusion, findings emerging from this study included the reappearance of PCGs in the engrafted bone marrow independently of a leukaemic relapse and the significant association of the activated BSA-I+ macrophage subset with the recovery of erythropoiesis.

Adult↗
PubMed2005

Use of midazolam and ketamine as sedation for children undergoing minor operative procedures.

OBJECTIVES: We used intravenous midazolam and ketamine for children undergoing minor operative procedures with satisfactory results. We aimed to further evaluate its efficacy and adverse effects in pediatric ward setting. METHODS: This was a prospective study of all children undergoing minor operations with sedation in our pediatric general and oncology wards from July 1998 to June 1999. The procedures included lumber puncture+/-intrathecal chemotherapy, bone marrow aspiration+/-trephine biopsy, central venous catheter removal, skin biopsy, or their combination. All sedation procedures were started with midazolam 0.1 mg/kg and ketamine 1 mg/kg; they were increased gradually to 0.4 and 4 mg/kg, respectively, if necessary. Heart rate and SaO2 were continuously monitored. RESULTS: Altogether, 369 minor operations were performed in 112 patients (male:female=2:1, median age 6 years, range 5 months-17 years). All achieved adequate sedation, with 96% within 30 s and 75% required just the starting dose. Younger children required a higher dosage (p=0.003 for midazolam, p<0.001 for ketamine). The median recovery time was 87 min, with no association with age, sex, or dosage of sedation, but was longer in patients having hallucination (p=0.001). Adverse effects included tachycardia (27.9%), increased secretion (17.6%), agitation (13.6%), nausea and vomiting (9.2%), hallucination (8.7%), desaturation (8.4%), and cataleptic reaction (0.8%). All desaturation episodes were transient and responded to oxygen supplement alone. None developed bronchospasm or convulsion. Some adverse effects were dose-related. Half of the children who received 0.3 mg/kg midazolam developed desaturation. CONCLUSIONS: Intravenous midazolam-ketamine can provide rapid, effective, and safe sedation for children undergoing minor operations in ward setting. Adverse effects are mild. Midazolam above 0.3 mg/kg should be used with caution.

Adolescent↗
PubMedDate not supplied

Bone marrow metastasis in Ewing's sarcoma and peripheral primitive neuroectodermal tumor: An immunohistochemical study.

Bone marrow metastases from small round cell tumors can present diagnostic difficulties. In this study, we assessed the value of immunohistochemistry, using two monoclonal antibodies to CD99, for the diagnosis of metastatic disease in bone marrow trephine specimens from patients with Ewing's sarcoma or primitive neuroectodermal tumor (PNET). The proportions of specimens showing metastases were 10.3% with routine staining and 20.7% with immunohistochemistry. The specimens that were negative on conventional light microscopy and positive with immunohistochemistry all showed other abnormalities. The results do not support the routine use of immunohistochemistry in specimens that are normal by conventional light microscopy, but indicate that useful information may be gained in cases where marrow histology is obscured by fibrosis, necrosis, or distortion artefact. Neither of the two antibodies tested was superior for this purpose.

12E7 Antigen↗