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I Aydogdu

Publications and source records attributed to I Aydogdu.

36 records · Page 2Linked to original sources
PubMed2000

Pathophysiological mechanisms of oropharyngeal dysphagia in amyotrophic lateral sclerosis.

We investigated the pathophysiological mechanisms of dysphagia in amyotrophic lateral sclerosis. Forty-three patients with sporadic amyotrophic lateral sclerosis were examined by clinical and electrophysiological methods that objectively measured the oropharyngeal phase of voluntarily initiated swallowing, and these results were compared with those obtained from 50 age-matched control subjects. Laryngeal movements were detected by a piezoelectric sensor and EMG of submental muscles, and needle EMG of the cricopharyngeal muscle of the upper oesophageal sphincter of both the amyotrophic lateral sclerosis and control groups was recorded during swallowing. Amyotrophic lateral sclerosis patients with dysphagia displayed the following abnormal findings. (i) Submental muscle activity of the laryngeal elevators, which produce reflex upward deflection of the larynx during wet swallowing, was significantly prolonged whereas the laryngeal relocation time of the swallowing reflex remained within normal limits. (ii) The cricopharyngeal sphincter muscle EMG demonstrated severe abnormalities during voluntarily initiated swallows. The opening of the sphincter was delayed and/or the closure occurred prematurely, the total duration of opening was shortened and, at times, unexpected motor unit bursts appeared during this period. (iii) During voluntarily initiated swallows there was significant lack of co-ordination between the laryngeal elevator muscles and the cricopharyngeal sphincter muscle. These results point to two pathophysiological mechanisms that operate to cause dysphagia in amyotrophic lateral sclerosis patients. (i) The triggering of the swallowing reflex for the voluntarily initiated swallow is delayed and eventually abolished, whereas the spontaneous reflexive swallows are preserved until the preterminal stage of amyotrophic lateral sclerosis. (ii) The cricopharyngeal sphincter muscle of the upper oesophageal sphincter becomes hyper-reflexic and hypertonic. As a result, the laryngeal protective system and the bolus transport system of deglutition lose their co-ordination during voluntarily initiated swallowing. We conclude that these pathophysiological changes are related mainly to the progressive degeneration of the excitatory and inhibitory corticobulbar pyramidal fibres.

Adult↗
PubMed2000

Thrombopoietic cytokines in patients with iron deficiency anemia with or without thrombocytosis.

Iron deficiency anemia is a cause of reactive thrombocytosis. A moderate increase in platelet numbers is common but sometimes counts may exceed 1,000 x 10(9)/l. The mechanisms causing reactive thrombocytosis are unclear. In this study, we evaluated 15 women with iron deficiency anemia and thrombocytosis (platelets >450 x 10(9)/l) and 16 women with iron deficiency anemia with normal platelet counts. Serum samples were taken before oral iron replacement therapy, after 1 and 3 months and at the end of replacement therapy. Thrombopoietin, erythropoietin (EPO), leukemia inhibitory factor, interleukin-6 and interleukin-11 levels were assayed. There was no change in the levels of thrombopoietic cytokines except for EPO. The correlation between high EPO levels and high platelet counts may suggest that EPO increases platelet counts, but the same EPO level changes can also be demonstrated in women with iron deficiency anemia but normal initial platelet counts. The fact that the levels of other cytokines remained unchanged during treatment suggests that either these cytokines have no effect on reactive thrombocytosis or the change in platelet counts in our patients is in a narrow range and is thus not affected by the cytokine levels.

Adolescent↗
PubMed2000

Mechanisms of dysphagia in suprabulbar palsy with lacunar infarct.

BACKGROUND AND PURPOSE: The objective of the present study was to investigate the neural mechanisms of dysphagia in suprabulbar palsy (SBP) with multiple lacunar infarct. METHODS: We evaluated the swallowing disorders of patients with SBP (n=34) and age-matched healthy control subjects (n=35) by means of an electrophysiological method that recorded the oropharyngeal swallowing patterns. With this method, dysphagia limit, the triggering of voluntarily initiated swallows, duration of laryngeal relocation time, and total duration of oropharyngeal swallowing were recorded and measured. In addition, the EMG behavior of the cricopharyngeal (CP) muscle of the upper esophageal sphincter was also assessed. RESULTS: In patients with SBP, the dysphagia limit in all except 1 patient was pathological with limits of <20-mL bolus volume, which is contrary to normal subjects, in whom the dysphagia limit exceeds the 20-mL bolus volume. Either triggering of swallowing reflex was delayed (P<0.04), or the swallow could hardly be triggered in 7 patients on the voluntary attempts for 3 mL water. Whenever the reflex swallowing could be triggered, it was slow and prolonged (P<0.01). The CP muscle of the upper esophageal sphincter appeared to have become hyperreflexic and incoordinated with laryngeal movements during swallowing. CONCLUSIONS: It was proposed that the progressive involvement of the excitatory and inhibitory corticobulbar fiber systems linked with the bulbar swallowing center is mainly responsible for the triggering difficulties of the swallowing reflex and for the hyperreflexic/incoordinated nature of the CP sphincter. In addition, the dysfunction of the extrapyramidal system has a specific role in the slowing of oropharyngeal swallowing and the accumulation of saliva in the mouth.

Adult↗
PubMed2000

Bilateral transient hearing loss associated with vincristine therapy: case report.

Vincristine, adriamycin, and dexamethasone (VAD) chemotherapy protocol is first-choice treatment in newly diagnosed multiple myeloma patients in many centers. Sudden hearing loss associated with vincristine therapy is a rarely observed event in the VAD protocol. We describe a 69-year old male patient diagnosed with multiple myeloma 7 months ago who developed sudden bilateral hearing loss related to vincristine therapy. This uncommon adverse effect of vincristine is discussed and the literature reviewed.

Aged↗
PubMed2000

A prospective randomized study of Chop versus Chop plus alpha-2B interferon in patients with intermediate and high grade non-Hodgkin's lymphoma: the International Oncology Study Group NHL1 Study .

UNLABELLED: The addition of a brief alpha interferon regimen to each CHOP induction cycle, plus one year of alpha interferon thrice weekly maintenance therapy, has no early effect on response rates or survival in patients with Intermediate or High grade cell NHL. BACKGROUND: The CHOP (Cyclophosphamide, Adriamycin. Vincristine, Prednisone) regimen is the most widely used first-line therapy for patients with Intermediate or High Grade (IG/HG) non-Hodgkin's lymphoma (NHL). Alpha 2b interferon (INF) enhances response rates and improves survival in low-grade NHL. The International Oncology Study Group (IOSG) conducted a prospective randomized study comparing CHOP alone or combined with INF in patients with IG/HG-NHL. The primary study aim was to compare the objective response rates in these patient cohorts. PATIENTS AND METHODS: Patients with a confirmed diagnosis of measurable NHL of International Working Formulation (IWF) groups D to H histology were randomized to receive CHOP alone or CHOP with 5Mu INF s.c. for 5 days on days 22 to 26 of each 28 day cycle with INF 5 million units (Mu) given three times per week subcutaneously for 52 weeks in those patients who responded to CHOP plus INF. RESULTS: The overall response rates were equivalent in both groups: CHOP alone (214 patients) 81% (complete 55%, partial 26%); CHOP plus INF (221 patients) 80% (complete 54%, partial 26%). At 36 months, the actuarial survival rate was equivalent in both groups. CONCLUSIONS: There is no apparent early advantage in terms of response or survival conferred by adding the study INF regimen to CHOP therapy for patients with IG/HG-NHL.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

A prospective randomized study of alpha-2b interferon plus hydroxyurea or cytarabine for patients with early chronic phase chronic myelogenous leukemia: the International Oncology Study Group CML1 study.

A prospective randomized international study of 143 patients showed no apparent early survival advantage conferred by combining cytarabine, rather than hydroxyurea, with INF as first-line CML therapy. Combinations of alpha-interferon (INF) and chemotherapeutic agents are currently first-line therapy for the majority of patients with chronic myeloid leukemia (CML). The International Oncology Study Group conducted a prospective randomized study comparing INF combined with hydroxyurea or cytarabine. The primary study aim was to compare the survival durations in these patient cohorts. Patients with early chronic phase CML were randomized to receive INF 5 million units (Mu) given five times per week subcutaneously plus hydroxyurea or cytarabine as required to achieve a complete hematologic response and to maintain a WBC count between 2x10(9)/L and 10x10(9)/L and a platelet count between 75x10(9)/L and 100x10(9)/L. Therapy continued as tolerated unless progressive or blast phase disease occurred. At 36 months, the actuarial survival rate was equivalent in both groups: HI group (79 patients) survival was 85% (95% CI, 68-100%), as compared to 95% (95% CI, 79-100%) in the CI group (64 patients). In conclusion if seems that there is no apparent early survival advantage conferred by combining cytarabine, rather than hydroxyurea, with INF as first-line CML therapy.

Adolescent↗
PubMed1998

Electrodiagnostic methods for neurogenic dysphagia.

OBJECTIVE: Swallowing mechanisms and neurogenic dysphagia have not been systematically studied by the EMG technique. It is desirable to evaluate neurogenic dysphagia for diagnostic and possibly for therapeutic purposes using electrophysiological methods. METHODS: The following methods were described: mechanical upward/downward movements of the larynx were detected using a piezoelectric sensor, while submental integrated EMG activity was recorded during dry and wet swallowing. The EMG activity of cricopharyngeal muscle of the upper oesophageal sphincter was also recorded in some normal subjects and patients. Piecemeal deglutition and the dysphagia limit were determined in all patients to detect dysphagia objectively. In this study 75 normal subjects and 177 neurological patients with various degrees of dysphagia were investigated. RESULTS: Voluntarily triggered oropharyngeal swallowing was commonly pathological in the majority of patients, with or without overt dysphagia. The dysphagia limit appeared to be an objective measure of the degree of dysphagia in more than 90% of patients. Pathophysiological mechanisms were different in at least three groups of patients with neurogenic dysphagia. In the group of patients with muscular disorders, laryngeal elevators were involved while the CP-sphincter was intact. The second group included patients with the clinical signs of corticobulbar fibre involvement such as amyotrophic lateral sclerosis and pseudobulbar palsy. In these patients, there was incoordination between paretic laryngeal elevators and hyperreflexic CP-sphincter. In the third group (patients with Parkinson's disease), the swallowing reflex was delayed and prolonged. CONCLUSIONS: EMG methods described in the present study are very useful for the diagnosis of neurogenic dysphagia, objectively and quickly. They are important to understand the physiological mechanisms for deglutition and its disorders.

Adolescent↗
PubMed1998

Clinical and electrophysiological evaluation of dysphagia in myasthenia gravis.

OBJECTIVE: To evaluate dysphagia at the oropharyngeal stage of swallowing and to determine the pathophysiological mechanisms of dysphagia in patients with myasthenia gravis. METHODS: Fifteen patients with myasthenia gravis with dysphagia and 10 patients without dysphagia were investigated by a combined electrophysiological and mechanical method described previously. Laryngeal movements were detected by a piezoelectric transducer and the related submental EMG (SM-EMG) and sometimes the EMG of cricopharyngeal muscle of the upper esophageal sphincter (CP-EMG) were recorded during dry or wet swallowing. The results of these electrophysiological variables were compared with those of normal age matched control subjects. RESULTS: In patients with myasthenia gravis with dysphagia, it was found that the time necessary for the larynx to remain in its superior position during swallowing and swallowing variability in successive swallows increased significantly compared with normal subjects and with patients with myasthenia gravis without dysphagia. The total duration of SM-EMG activity was also prolonged in both groups but more severely in the dysphagic patients. Electromyographic activity of the CP sphincter was found to be normal in the dysphagic patients investigated. All the patients with myasthenia gravis with dysphagia had pathological dysphagia limits (<20 ml water) whereas other patients except two, were within normal limits. CONCLUSIONS: Because the electrophysiological variables related to oropharyngeal swallowing were prolonged even in patients with myasthenia gravis without dysphagia, it is concluded that the submental and laryngeal elevators are involved subclinically in myasthenia gravis and, because of compensating mechanisms, the patient may not be dysphagic. As the CP-EMG behaviour was found to be normal, a coordination disorder between normal CP sphincter muscle and the affected striated muscles of the laryngeal elevators may be one of the reasons for dysphagia in myasthenia gravis. This method also made it possible to investigate the myasthenic involvement in the laryngeal elevators that cannot be evaluated by other electrophysiological methods in myasthenia gravis.

Adult↗
PubMed1998

Serum erythropoietin levels in patients with leukemia on cytostatic treatment.

Anemia is the major stimulus for erythropoietin (Epo) secretion. Various studies have reported increase of Epo following chemotherapy. The mechanism of this phenomenon is not yet clarified. In this study, the serum Epo levels have been evaluated before, during (7 and 14 days), and after (day 25) chemotherapy in patients with acute myeloblastic leukemia (n = 13) and lymphoblastic leukemia (n = 4). As a control group, 12 healthy age-matched subjects were evaluated. Epo levels were high in untreated leukemia patients compared to controls and continued to increase following chemotherapy. There was no significant difference in post-treatment values of Epo as compared with pre-treatment levels. In patients with pre-treatment values of Hb < or = 9 g/dl, Epo levels were inversely correlated with Hb (r = 0.552; p < 0.05). This correlation disappeared during and following treatment. There was no correlation between Epo levels and hematological or biochemical parameters. Therefore, elevated levels of Epo regardless of anemia may be due to a response to tissue hypoxia or increased synthesis of Epo in liver or bone marrow.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

Administration of MINE protocol in untreated patients with intermediate and high grade non-Hodgkin's lymphoma.

In recent years, more effective and less toxic treatment protocols have been developed to increase the cure rates in intermediate and high grade non-Hodgkin's lymphoma (NHL). This study was undertaken to investigate the efficacy and toxicity of MINE (ifosfamide, mesna, mitoxantrone and etoposide) combination chemotherapy in patients with intermediate and high grade NHL. Twenty-one patients (16 male, 5 female; age between 26 and 70 years) with NHL were included in the study. An overall response rate of 73% and complete response rate of 56% were achieved and survival rate for responding patients was 80% at the 48th month. Side effects including mild myelosuppression, nausea/vomiting and alopecia were observed. MINE combination seems to be effective and well tolerated without significant toxicity as a first-line therapy in patients with intermediate or high grade NHL.

Adult↗
PubMedDate not supplied

Oxidant/antioxidant parameters and their relationship with chemotherapy in Hodgkin's lymphoma.

This study investigated changing levels of serum oxidant/antioxidant with chemotherapy and their relation to treatment in 34 Hodgkin's lymphoma patients. The patient population consisted of 19 males and 15 females. Mean age was 30.41 +/- 12.08 years. All patients received the adriamycin, bleomycin, vincristine and dexamethasone (ABVD) treatment protocol. Blood samples were taken before treatment, and on days 1 and 7 during treatment for measurement of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), malondialdehyde (MDA), nitric oxide (NO) and enzyme activities. After ABVD treatment, mean free radical levels were increased and antioxidant levels were significantly decreased in the serum. ABVD treatment results in an increase of free radical levels and a decrease of antioxidant levels in the serum of patients with Hodgkin's lymphoma.

Adolescent↗