Biomedical subjects

M Ozcan

Publications and source records attributed to M Ozcan.

At least 55 records · Page 3Linked to original sources

PubMed2001

Allogeneic peripheral blood stem cell transplantation for severe aplastic anemia.

Allogeneic peripheral blood stem cell transplantation (PBSCT) is rarely applied for the treatment of severe aplastic anemia (SAA) because of questionable durability of engraftment and increased risk of graft versus host disease (GVHD). We performed allogeneic PBSCT in 3 SAA patients from their human leukocyte antigen (HLA)-identical siblings. One received bone marrow after conditioning with cyclophoshamide (Cy) plus antithymocyte globulin. He had a second transplant with peripheral blood stem cells from the original donor because of a graft failure (GF). Two other patients received PBSCT as a first option, with Cy as the only conditioning drug. The 3 patients received short-term methotrexate and cyclosporine as a postgrafting immunosupression. In the latter 2 cases, no GF has been observed, and a successful and complete hematological recovery was achieved and maintained for 28 and 25 months, respectively. In conclusion, PBSCT provides a quick and complete hematological recovery in SAA patients.

Adolescent↗

PubMed2001

A case of familial Mediterranean fever with amyloidosis as the first manifestation.

We describe a 22-year-old Turkish woman with nephrotic syndrome who had a history of acute myelocytic leukemia. After careful clinical evaluation, the patient underwent a renal biopsy. Light microscopic examination showed deposition of Congo-positive material both in the mesangium and around the small vessels. By histochemical analyses, the deposited material was proved to be amyloid A (AA). Because the patient's history did not reveal any event that might explain the development of secondary amyloidosis, she was screened for mutations causing familial Mediterranean fever (FMF) and was found to be homozygous for the M694V mutation by denaturing gradient gel electrophoresis. We recommend that FMF-Phenotype II and the development of amyloid nephropathy, before or without other symptoms of FMF, should be kept in mind in the face of unexplained proteinuria/amyloidosis, especially in high-risk ethnic groups.

Adult↗

PubMed2001

Effects of human amniotic fluid on peritendinous adhesion formation and tendon healing after flexor tendon surgery in rabbits.

The effect of the topical application of human amniotic fluid (HAF) on peritendinous adhesion formation and tendon healing was investigated in 32 New Zealand adult rabbits. The long flexor tendons of the digits of each hind paw were completely divided and repaired with a modified Kessler technique. The rabbits were randomly divided into 4 experimental groups according to the type of repair used: sheath excision, sheath excision and local HAF application, sheath repair, and sheath repair and local HAF application. The extent of adhesions and the healing status of the tendons were macroscopically and histologically evaluated at 12 weeks. Tensile strength of the repaired tendons was measured biomechanically at 20 weeks. The least adhesion and the best healing were observed in tendons treated with sheath repair and HAF application. Tendons treated with HAF had significantly higher tensile load values. Topical application of HAF immediately after tenorrhaphy is significantly effective in preventing peritendinous adhesion formation without impairment of tendon healing in this rabbit model.

Amniotic Fluid↗

PubMed2001

Biological suppression of aflatoxicosis in Japanese quail (Coturnix coturnix japonica) by dietary addition of yeast (Saccharomyces cerevisiae).

The amelioration of aflatoxicosis in Japanese quails was examined by the dietary addition of live yeast (Saccharomyces cerevisiae; SCE). Yeast incorporated into the diet at 1 g kg(-1) was evaluated for its ability to reduce the deleterious effects of 2.5 mg total aflatoxin (AF; 82.30 per cent AFB1, 2.06 per cent AFB2, 7.68 per cent AFG1 and 7.96 per cent AFG2) kg(-1)diet on growing Japanese quail chicks from 10 days to 45 days of age. Forty 10-day-old Japanese quail chicks were assigned to 2x2 factorial arrangement of treatments (control, AF, SCE, AF plus SCE) each consisting of 10 quails. The performances of birds were evaluated. The AF treatment significantly and dramatically decreased food consumption and body-weight gain from the first week onwards. The significant adverse effect of AF on the food conversion ratio was also determined from week 1 to the end of the experiments. The addition of SCE to the AF -containing diet significantly reduced these deleterious effects of AF on food consumption, body-weight gain and food conversion ratio. Compared to controls, the cumulative body weight gain was reduced by 37 per cent among the quails consuming AF without SCE, but increased 15 per cent for the birds fed AF plus SCE. Interestingly, the single inclusion of SCE to the AF-free diet provided significant improvements in all the investigated growth performances of birds (approximately 40 per cent) compared to controls.

Aflatoxins↗

PubMed2001

Allogeneic hematopoietic cell transplantation without myeloablative conditioning for patients with advanced hematologic malignancies.

BACKGROUND: The effect of allogeneic hematopoietic cell transplantation (alloHCT) on hematologic malignancies is based on the graft-versus-malignancy effect. Obtaining this effect with reduced toxicity has been possible by non-myeloablative (NMA) alloHCT. Once mixed chimeric status, and host versus graft with graft versus host tolerance are achieved, further strengthening of chimerism and graft-versus-malignancy effect can be obtained by donor lymphocyte infusions (DLIs) when needed. METHODS: The patient group consisted of 13 patients with advanced hematological malignancies: seven had CML, four of them in blastic-, two in chronic- and the remainder in accelerated-phase; four patients with AML, refractory or in second remission state; one patient with primary refractory secondary AML; and one patient with ALL relapsed after alloHCT. Conditioning regimen consisted of fludarabine 30 mg/m(2)/day for 6 days and anti-T-lymphocyte globulin (ATG) 10 mg/kg/day for 4 days as immunosuppressive. Ara-C or Bu or melphalan were used as the cytoreductive component. All transplants were performed using HLA-identical sibling donors' peripheral blood hematopoietic cells, after priming with filgrastim. Post-transplant GvHD prophylaxis was achieved with CsA alone in 10 patients, and with CsA plus mycophenolate mofetil in the last three patients. RESULTS: Median follow-up is 3 months (range, 0-20) for all the patients and 6 months (range, 2-15) for the live patients. Donor chimerism was shown in 10 patients, not regarding any pretransplant feature. DLIs were performed in seven patients after transplantation and two of them achieved complete chimeric status and molecular remission. Two CML patients in blastic phase (CML-BP), and the primary refractory secondary AML patient did not respond to procedure. In four patients, drug therapy in conventional doses was added to post-transplant DLIs for their relapsed or refractory diseases. Two patients with AML in second CR, and another CML-BP patient, relapsed or progressed after transplantation. A patient with CML-BP achieved CR and full donor chimerism after transplantation, but developed refractory post-transplant lymphoproliferative disease in the 19th month. Two patients with refractory AML, one patient with relapsed ALL and two patients with CML in chronic phase were in complete chimeric status and free of disease signs. Acute GvHD, Grade II-III, was observed in five patients, and two of them developed secondary progressive chronic GvHD subsequently. We observed one early death in a platelet transfusion refractory blastic phase CML patient due to intracranial hemorrhage. Procedure-related severe toxicity was not observed, either in standard-risk patients or stem-cell donors. DISCUSSION: Establishing engraftment with donor chimerism was the first successful step in this approach. The second step, which was the result of the graft-versus-malignancy effect, could be seen in most of the patients, but was not sustained in all of them because of the aggressiveness of their malignancy. It can be suggested that the immunotherapeutic efficacy of this approach could be more successful, and with acceptable toxicity, when performed in patients with minimal residual disease. The role of NMA conditioning, and of the treatment in standard disease indications, remains to be determined in further studies.

Adult↗

PubMed2001

Value of combined 67Ga and 99Tc(m)-human immunoglobulin G whole-body scanning in malignant lymphoma.

Human immunoglobulin G labelled with 99Tc(m) (99Tc(m)-HIG) is an agent introduced for the localization of inflammatory lesions. There is also a limited number of reports concerning the uptake of this agent by malignant lesions. The aim of this study was to evaluate the uptake of 99Tc(m)-HIG by lymphoma. Twenty-three patients (five female, 18 male) with known Hodgkin's or non-Hodgkin's lymphoma for a period of 2-6 years (mean 4.2 years) and which, by using computed tomography (CT), showed recurrence, were included in the study. The patients were aged between 32 and 68 years (mean 38 +/- 5 years). No evidence of inflammation or infection was seen in any of these patients. CT, 99Tc(m)-HIG and a 67Ga scan were performed in the same week. CT showed abdominal involvement in 17 patients, pelvic involvement in 11, and thorax involvement in 11. 99Tc(m)-HIG showed higher sensitivity (94.1%) in the abdomen, a similar sensitivity (63.6%) in thorax, but lower (18.1%) in pelvic area than for 67Ga. 99Tc(m)-HIG was found to be more useful for the evaluation of abdominal involvement compared to 67Ga due to gastrointestinal excretion of the latter. The resolution of 67Ga was better than 99Tc(m)-HIG in thorax and pelvis. Using 99Tc(m)-HIG and 67Ga together in lymphoma may increase sensitivity.

Adult↗

PubMed2001

Whole blood tissue factor procoagulant activity remains detectable during severe aplasia following bone marrow and peripheral blood stem cell transplantation.

Using a novel whole blood assay, we recently demonstrated that tissue factor procoagulant activity (TF PCA) is present in normal individuals. Preliminary experiments suggested that this activity is localized in the mononuclear cell fraction. Postulating that whole blood TF PCA would therefore be undetectable when monocytes and neutrophils are absent from peripheral blood, we assayed TF PCA during the peri-transplant period in 15 consecutive patients undergoing allogeneic (n = 12) or autologous (n = 3) bone marrow transplantation (BMT) or peripheral blood stem cell transplantation (PBSCT). Baseline (pre-transplant) mean TF PCA was higher in patients compared to normal controls (P <0.005). Unexpectedly, although TF PCA during the period of profound aplasia was significantly reduced compared to baseline (p <0.05), fully 55% of the initial activity remained detectable. During the engraftment phase, TF PCA returned to pre-transplant levels, with a linear correlation between monocyte counts and TF PCA (r = 0.63). In contrast to normal whole blood, incubation of aplastic samples with E. Coli lipopolysaccharide ex vivo failed to induce TF PCA. Throughout the period of study--but especially during the aplastic phase--the absolute number of circulating endothelial cells (CECs) that were TF antigen-positive was increased compared to normals (P <0.001). However, removal of these cells from whole blood samples failed to significantly diminish total TF PCA indicating that CECs alone could not account for the detectable TF PCA during aplasia. We conclude that neither circulating mature myelo-monocytic cells nor endothelial cells can account for all the functionally intact TF in peripheral blood. Further studies are needed to identify the other source(s) of TF PCA.

Adolescent↗

PubMed2001

Laser-evoked potentials to noxious stimulation during hypnotic analgesia and distraction of attention suggest different brain mechanisms of pain control.

Psychological accounts of hypnosis have hypothesized that hypnosis and attention might share similar mechanisms and that hypnosis simply represents an extensive state of reduced attention. This assumption implies that reports of pain and electrocortical brain responses to painful stimulation should be similarly reduced when subjects are exposed to suggestions of hypnotic analgesia (HA) or requested to distract their attention from painful stimuli (distraction of attention: DA) as compared to a control condition (CC). To test this hypothesis, we recorded event-related electrical brain potentials to noxious laser-heat stimuli and pain reports during HA, DA, and CC from subjects highly susceptible to hypnotic suggestions. Pain reports were significantly reduced during HA and DA as compared to CC. The amplitudes of the late laser-evoked brain potential (LEP) components N200 and P320 were also significantly smaller during DA than during CC. However, no significant difference of these late LEP amplitudes was obtained for HA as compared to CC. Results indicate that hypnotic analgesia and distraction of attention represent different mechanisms of pain control and involve different brain mechanisms.

Adult↗

PubMed2001

Concomitant vagal neurofibroma and aplasia of the internal carotid artery in neurofibromatosis type 1.

We report the case of a patient with neurofibromatosis type 1 who had both aplasia of an internal carotid artery (ICA) and a vagal neurofibroma. To our knowledge, this is the first report in the literature of the simultaneous presence of these two rare disorders in a single patient. We believe that this is also the first report of an absence of an ICA in a patient with neurofibromatosis type 1. The patient was a 19-year-old woman who complained of a slowly growing neck mass. The mass occupied the right parapharyngeal space and upper cervical region. The patient had no other masses on physical examination, but widespread café au lait spots were evident. This led us to suspect the presence of a vagal neurofibroma. The tumor was removed, and pathology confirmed the diagnosis. No intracranial aneurysms were detected on cerebral angiography.

Adult↗

PubMed2001

Reliability of radiological parameters measured on anteroposterior pelvis radiographs of patients with developmental dysplasia of the hip.

In order to evaluate the reliability of radiological parameters, we retrospectively reviewed the anteroposterior pelvic x-rays of 30 hips in 15 patients with developmental dysplasia of the hip. The following parameters were studied: acetabular index, center-edge angle, c/b ratio, Sharp's angle and teardrop figure. Each of the two authors measured the parameters twice on two separate days. Statistical assessment of the interobserver and intraobserver reliability was performed. The measurements of acetabular index and c/b ratio were reliable according to both intra- and interobserver reliability analysis, whereas center-edge angle, teardrop figure and Sharp's angle evaluations were reliable in the intraobserver comparisons but not in the interobserver comparisons. In conclusion, both acetabular index and c/b ratio may be used safely in the evaluation of developmental dysplasia of the hip.

Child, Preschool↗

PubMed2001

A clinical evaluation of ceramic inlays bonded with different luting agents.

PURPOSE: The purpose of this study was to evaluate the clinical performance of a fired ceramic inlay system bonded with three different luting agents. MATERIALS AND METHODS: A total of 45 Ducera LFC ceramic inlays (12 in premolars, 33 in molars) were placed in 26 patients. Fifteen of the inlays were inserted with one of three different luting agents: (1) Variolink High Viscosity, (2) Enforce, and (3) Geristore. The restorations were evaluated for a period of 3 to 46 months, with a mean of 26.3 months after insertion using modified USPHS criteria. The evaluation period ended when the restoration had to be replaced due to fracture or secondary caries. Postoperative sensitivity was determined by direct questioning. Kaplan-Meier statistical analysis was used to calculate the survival rate of the inlays. Selected restorations were further evaluated indirectly with SEM. RESULTS: The fracture rates observed for Variolink, Enforce, and Geristore were 13%, 13%, and 33%, respectively. There was a high rate of early bulk fracture, seen mainly within 12 months, for inlays luted with Geristore. For all groups, secondary caries was found to be relatively low. The inlays in all luting agent groups showed acceptable color match and surface roughness scores during the whole evaluation period. SEM observation revealed that the deterioration of marginal adaptation was found to be more severe for inlays luted with Geristore, and that the rate of submargination was also higher for Geristore-luted inlays in comparison to those luted with Variolink and Enforce. CONCLUSION: The use of a polyacrylic acid modified glass ionomer, Geristore, resulted in a higher fracture rate and loss of marginal adaptation in fired ceramic inlays. The marginal adaptation of the luting agent was more durable at the enamel interface than that at ceramic interface.

Adult↗

PubMed2000

Circulating CD44 and intercellular adhesion molecule-1 levels in low grade non-hodgkin lymphoma and B-cell chronic lymphocytic leukemia patients during interferon-alpha-2a treatment.

BACKGROUND: Despite published reports regarding the association of elevated circulating CD44 and CD54 levels with unfavorable outcome in non-Hodgkin lymphoma (NHL) and chronic lymphocytic leukemia (CLL), little is known about therapy-related changes in either adhesion molecule. In an attempt to evaluate the effect of interferon-alpha (IFNalpha), the authors measured serum CD44 (sCD44) and sCD54 in 22 low grade NHL and 14 CLL patients. METHODS: Twenty-six patients fulfilling the criteria for therapy received daily doses of 3 x10(6) IU IFNalpha-2a. Ten patients not requiring therapy also were observed for the same period. Fasting sera were collected at baseline and in 4 monthly intervals from all patients including the IFNalpha-treated (Group 1) and the untreated group (Group 2). RESULTS: Higher baseline sCD44 values were observed in Group 1 as compared with the Group 2 patients (P = 0.057). Within Group 1, patients were further divided between those who responded to IFNalpha, referred to as responders, and those who did not respond to IFNalpha, known as nonresponders. Responders showed a gradual decrease in sCD44 starting at the 4th month until the 12th month (P = 0.003, P = 0.002, and P = 0.01). Neither a difference in baseline nor an IFNalpha effect on the sCD54 levels could be shown. Soluble CD44 levels between responders and nonresponders were not different at the baseline but were significantly lower in responders, starting at month 4 and continuing throughout the therapy period (P = 0.04, P = 0.017, and P = 0.043). This decrease did not accompany a leukocyte or lactate dehydrogenase decrease and was not correlated with an early disappearance of the clinical findings. Similarly, after treatment, the sCD44 values of Group 1 were lower than the Group 2 levels at months 4 and 8 (P = 0.007 and P = 0.05, respectively). CONCLUSIONS: Soluble CD44, but not sCD54, can be used for monitoring therapy in patients with low grade NHL and CLL who have received IFNalpha, and for deciding whether further IFN therapy is necessary for those patients who have not responded to IFNalpha over a previous 12-month period.

Adolescent↗

PubMed2000

Effect of Valsalva maneuver on surface electrocardiographic P-wave dispersion in paroxysmal atrial fibrillation.

The purpose of this study was to investigate the effect of the Valsalva maneuver on P-wave durations and dispersion. After the Valsalva maneuver, we found that maximum P-wave duration increased, minimum P-wave duration decreased, and P-wave dispersion increased in controls, whereas the opposite was true for unselected patients with paroxysmal AF. It was concluded that patients with paroxysmal AF performing the Valsalva maneuver normalized their P-wave dispersion, thereby correcting the inhomogeneous intra-atrial conduction.

Anti-Arrhythmia Agents↗

PubMed2000

Allogeneic peripheral blood stem cell transplantation for standard risk leukemia: experience of Ibni Sina Hospital.

Fifty-three patients with standard risk leukemia who underwent allogeneic peripheral blood stem cell transplantation (alloPBSCT) from their HLA-identical siblings were analyzed for engraftment, incidence and severity of GVHD, and relapse rate. Standard risk leukemia was defined as AML in first complete remission or CML in first chronic phase within the first year after diagnosis. The median age was 34.5 years (range 13-47). Stem cells were mobilized by using 10 microg/kg G-CSF subcutaneously for 5 days. A median of 5. 7 (2.1-21.4) x 106/kg CD34+ cells was collected over a median of 2 (range 1-5) apheresis procedures. Cyclosporin A (CsA) plus short-course MTX were used for GVHD prophylaxis. Recovery to granulocytes >0.5 x 109/l and platelets >20 x 109/l occurred at a median of day +13 (range 8-32) and +13 (range 8-51), respectively. Day +100 transplant-related mortality was 13.2% (7/53). Acute GVHD occurred in 20 of 49 (41%) evaluable patients and only six (12.3%) of them had severe disease (grade III-IV). Chronic GVHD occurred in 30 of 42 (71.4%) evaluable patients. Relapse rate at 2 years was 7. 5%. The median overall and leukemia-free survivals were 22 (4-44) and 20 (3-44) months, respectively. Estimated 4 year leukemia-free and overall survival rates were 60% and 62%, respectively. In conclusion, alloPBSCT in standard risk leukemia seems to be associated with a low relapse rate and no increased risk of acute GVHD, but there is a trend for higher incidence of cGVHD. Bone Marrow Transplantation (2000) 25, 1229-1232.

Adolescent↗

PubMed2000

An experimental study of bilateral repositioning of the Stensen's duct orifices with autologous vein and artery grafts in dogs.

Sialorrhoea is an indication of dysfunction in the coordination of the swallowing mechanism. Disturbance in this coordination results in excess pooling of saliva in the anterior mouth and resultant drooling. Several surgical techniques have been described for the management of sialorrhoea. In this experimental study, we planned to try a more safe and physiologic technique by repositioning of the parotid duct orifices into the glossopalatal arch, using autologous free grafts of vein and artery in dogs. Ten adult dogs were used. In each dog, both of the parotid duct orifices were included in the study. The surgical procedure involved the dissection of both parotid duct orifices and their relocation via a submucosal tunnel into the glossopalatal arch, using a vein graft for the right side and an artery graft for the left side. Functional assessment was based on the clinical observations and retrograde sialography done on the 60th day. Results were excellent. No stricture or obstruction was noted. Histological examinations done on the 90th day showed the replacement of endothelium by multilayered cubic Stensen's duct epithelium in both artery and vein grafts. There was no difference between the results of artery and vein grafts. Surgical transposition of Stensen's duct into the glossopalatal arch with autologous vein or artery graft is a safe technique which may be used in clinical cases of drooling as an alternative to the other techniques described.

Animals↗

PubMed2000

Use of the distally-based radial forearm flap supplied by the dorsal carpal arch, or palmar carpal arch, or both, in mutilating injuries. Two case report.

The distally-based radial forearm flap is safe, easy, and versatile as a regional, one-stage procedure to reconstruct soft tissue defects of the hand. However, there is a general perception that the deep and superficial palmar arches have to be intact to raise a distally-based radial forearm flap. We successfully used two flaps supplied by the dorsal carpal arch, or the palmar carpal arch, or both, despite the fact that the deep and the superficial palmar arches were damaged in mutilating injuries.

Adult↗

PubMed2000

Soluble adhesion molecules (sICAM-1, sL-Selectin, sE-Selectin, sCD44) in healthy allogenic peripheral stem-cell donors primed with recombinant G-CSF.

BACKGROUND: We analysed the effects of rhG-CSF (Amgen-Roche, USA) on serum changes of four soluble adhesion molecules (SAM) (sICAM-1, sL-Selectin, sE-Selectin and sCD44) in healthy peripheral allogeneic stem-cell transplantation donors and their correlation with acute GvHD and effect on engraftment kinetics. METHODS: Serum SAM of 15 consecutive healthy HLA identical-sibling donors (median age 30 years, male:female ratio, 7:8) were monitored using a commercial ELISA Kit (Bender Med, Austria) prior to, on the day of first apheresis and 24 h after the cessation of rhG-CSF (10 microg/kg/day s.c. on 5 days) administration. Leukapheresis was started on the fifth day of rhG-CSF administration, using a continuous-flow blood separator (Cobe Spectra, COBE BCT, Inc, Lakewood, CO). Apheresis cycles were continued daily until a target of 4.0 x 10(6) CD34(+) cells/kg was reached. RESULTS: The results indicate a steady rise of sL-Selectin, sE-Selectin, and sCD44, but not of sICAM-1. Median number of mononuclear cells (MNC) and CD34(+) cells transfused were 7.7x 10(8)/kg and 6.0 x 10(6)/kg, respectively. There was a near-significant correlation between the sL-Selectin levels and CD34(+) cell yield (r = 0.49, 0.06). Median granulocyte and platelet engraftment days were 11 (10-18) and 12 (9-33), respectively. There was a significant inverse correlation between the CD34(+) cell dose and granulocyte levels (r = -0.68, p = 0.022), but not for platelet engraftment. The only correlation between SAM levels and engraftment was for sICAM-1 levels. Increasing sICAM-1 levels were a sign of prolonged neutropenia (r = 0.72, p = 0.011). No correlation between the apheresis day serum levels of adhesion molecules and acute GvHD was documented. DISCUSSION: Analysis of sICAM-1, sL-Selectin, sE-Selectin and sCD44 levels during allogeneic PBSC apheresis did not reveal any significant effect on engraftment and GvHD, except the correlation of sL-Selectin levels and collected CD34(+) cells. More research and data about the role of not only SAM levels, but also antigenic expression of SAM are required to enlighten leukocyte-endothelial cell interactions and egress of stem cells during G-CSF administration.

Adult↗

PubMed2000

A modified reversed digital island flap incorporating the proper digital nerve.

A standard reversed digital artery flap is based on the digital artery and vena comitantes alone, leaving the proper digital nerve intact. In the authors' opinion, in situations in which the fingertip pulp is lost completely, it is unnecessary to leave the nerve in situ. Using their technique, the proper digital nerve is included in the pedicle. The pedicle is raised as a monobloc of fatty tissue containing the small veins important for drainage. The proper digital nerve in the flap is sutured to the stump of the opposite proper digital nerve. They found this flap to be very reliable, and quite easy and quick to raise. A patient is presented and discussed in detail.

Adult↗