Use of H(2) (15)O-PET for investigating perfusion changes in pelvic tumors due to regional hyperthermia.

PURPOSE: An increase in tumor oxygenation and perfusion due to hyperthermia has been reported for experimental tumors. The present study was performed to investigate this hypothesis in patients who underwent regional hyperthermia. METHODS: Twenty-seven patients with primary or recurrent pelvic tumors were included in this study. Prior to and up to 1 h after regional hyperthermia, perfusion and partition coefficient were quantitatively determined by utilizing H(2) (15)O-PET. First pass PET images were fused with the segmented common iliac artery from separately acquired CT scan. The arterial input function was extracted from the common iliac arteries using the dynamic PET images and the fused CT. The fused images were also used to extract tumor activity-time curves. Perfusion was calculated from the total tumor curves with correction for arterial spill-over. Changes in perfusion and partition coefficient were analyzed and correlated with various treatment parameters. RESULTS: Heating under hyperthermia conditions significantly increased the partition coefficient for pelvic tumors (P = 0.005). The increase correlated with the duration of hyperthermia and was found in patients treated for more than 1 h and persisted for more than 1 h after the end. Significant changes in perfusion were not observed. Perfusion had recurred to initial values 20 min after heating. CONCLUSIONS: The increase in partition coefficient reflects an increased diffusion distance of radio-labeled water. Therefore water diffusion is increased due to hyperthermia. Analogous to water diffusion, the diffusion of inert gases is also facilitated, improving the oxygenation of hypoxic tumor cells. Our results suggest that tumor oxygenation can probably be enhanced by regional hyperthermia for a period of more than 1 h after heating, provided hyperthermia is applied for at least 60 min. The effect was observed to be reversible within one week.

Eating disorders: Prevalence in the student population of Mysore, South India.

BACKGROUND: Eating disorders (ED), once known to be a rarity are now commonplace all over the world. However, studies on ED in the Indian population are still very rare to come across. AIM: We made an attempt to study the prevalence of ED in the student population of Mysore, South India. MATERIALS AND METHODS: A total of 1600 students aged 15-25 years and residing in Mysore were surveyed using two standardized questionnaires. Among the 417 students who scored higher in the questionnaires, 35 students were recruited as participants. Another 35 students with low scores were considered controls. A series of anthropometric measurements were conducted along with the establishment of a register on their well-being and family history. Hemoglobin (Hb) content was measured using a Hb test kit from Beacon Diagnostics Pvt., Ltd., India. Statistical analyses were performed using SPSS version 14.01 software utilizing analysis of variance tool. RESULTS: It was found that 26.06% of participants were prone to ED due to their abnormal eating attitudes. We also observed significant differences between the controls and participants in relation to various parameters such as weight, waist and hip circumferences, body mass index, basal metabolic rate, fat percentage. Hb content was normal in both controls and participants. The establishment of the register also revealed that the onset of menstruation differed significantly between the controls and participants. CONCLUSIONS: We arrived at the conclusion that ED are definitely prevailing among the students of Karnataka and have a profound effect on the mental and physical health of the students with eating discrepancies.

Corrections of arterial input function for dynamic H215O PET to assess perfusion of pelvic tumours: arterial blood sampling versus image extraction.

Assessment of perfusion with 15O-labelled water (H215O) requires measurement of the arterial input function (AIF). The arterial time activity curve (TAC) measured using the peripheral sampling scheme requires corrections for delay and dispersion. In this study, parametrizations with and without arterial spillover correction for fitting of the tissue curve are evaluated. Additionally, a completely noninvasive method for generation of the AIF from a dynamic positron emission tomography (PET) acquisition is applied to assess perfusion of pelvic tumours. This method uses a volume of interest (VOI) to extract the TAC from the femoral artery. The VOI TAC is corrected for spillover using a separate tissue TAC and for recovery by determining the recovery coefficient on a coregistered CT data set. The techniques were applied in five patients with pelvic tumours who underwent a total of 11 examinations. Delay and dispersion correction of the blood TAC without arterial spillover correction yielded in seven examinations solutions inconsistent with physiology. Correction of arterial spillover increased the fitting accuracy and yielded consistent results in all patients. Generation of an AIF from PET image data was investigated as an alternative to arterial blood sampling and was shown to have an intrinsic potential to determine the AIF noninvasively and reproducibly. The AIF extracted from a VOI in a dynamic PET scan was similar in shape to the blood AIF but yielded significantly higher tissue perfusion values (mean of 104.0 +/- 52.0%) and lower partition coefficients (-31.6 +/- 24.2%). The perfusion values and partition coefficients determined with the VOI technique have to be corrected in order to compare the results with those of studies using a blood AIF.

Oxidative stress and abnormal lipid profile are common factors in students with eating distress.

Numerous studies on complications associated with eating disorders have been conducted worldwide. However such studies are limited in the Indian scenario. Hence, we attempted to analyse the presence of oxidative stress along with total lipid profiling of students with eating distress in Mysore, South India. A biochemical test panel was conducted using serum samples of controls and subjects. Results were statistically analyzed using SPSS software version 14. Analysis of variance was used to identify significant differences between study groups. Variations in all parameters confirmed the occurrence of oxidative stress and abnormal lipid contents in students prone to eating disorders.

Evaluation of acrosome intactness status in male infertility in Mysore, South India.

BACKGROUND AND OBJECTIVE: The objective of this study is to determine the status of acrosome intactness in different infertile conditions among men who have attended the Mediwave Fertility Research Center, Mysore, South India. MATERIALS AND METHODS: A total of 70 infertile and 20 control subjects were employed in the study. Infertile subjects were classified into different conditions according to the WHO protocol. The data obtained was statistically analyzed. RESULTS: In the present study, seven different infertile conditions were reported. For the acrosome intactness test, except oligospermia, all other conditions recorded a statistically significant value (P < 0.05) compared with the control group. CONCLUSIONS: The present study shows the decreased acrosomal enzyme activity in infertile males compared with fertile males. If diagnosed and treated earlier, it may help in the success of the in vitro fertilization technique.

Hyperthermia in combined treatment of cancer.

Hyperthermia, the procedure of raising the temperature of tumour-loaded tissue to 40-43 degrees C, is applied as an adjunctive therapy with various established cancer treatments such as radiotherapy and chemotherapy. The potential to control power distributions in vivo has been significantly improved lately by the development of planning systems and other modelling tools. This increased understanding has led to the design of multiantenna applicators (including their transforming networks) and implementation of systems for monitoring of E-fields (eg, electro-optical sensors) and temperature (particularly, on-line magnetic resonance tomography). Several phase III trials comparing radiotherapy alone or with hyperthermia have shown a beneficial effect of hyperthermia (with existing standard equipment) in terms of local control (eg, recurrent breast cancer and malignant melanoma) and survival (eg, head and neck lymph-node metastases, glioblastoma, cervical carcinoma). Therefore, further development of existing technology and elucidation of molecular mechanisms are justified. In recent molecular and biological investigations there have been novel applications such as gene therapy or immunotherapy (vaccination) with temperature acting as an enhancer, to trigger or to switch mechanisms on and off. However, for every particular temperature-dependent interaction exploited for clinical purposes, sophisticated control of temperature, spatially as well as temporally, in deep body regions will further improve the potential.

Regional pelvic hyperthermia as an adjunct to chemotherapy (oxaliplatin, folinic acid, 5-fluorouracil) in pre-irradiated patients with locally recurrent rectal cancer: a pilot study.

The aim of this study was to evaluate the feasibility and toxicity of a novel hyperthermic chemotherapy approach for patients with locally recurrent adenocarcinoma of the rectum. All patients were pre-irradiated (> or = 45 Gy) and had histologically proven pelvic recurrence. Hyperthermic chemotherapy was applied according to a modified 'OFF'-schedule with weekly infusions of 43 mg/m2 of oxaliplatin (i.v., 120 min), 500 mg/m2 of folinic acid (i.v., 120 min) and 2.6 g/m2 of continuous infusional 5-fluorouracil (24 h) for 6 consecutive weeks. Oxaliplatin was started in parallel to pelvic radiofrequency hyperthermia that was provided by the BSD 2000-system. A total of 67 applications were administered to nine patients and were well tolerated. A total of 55/67 (82%) chemotherapy courses were applied without dose-reduction. In 62/67 (93%) hyperthermia sessions, a treatment time of > 60 min was maintained. Tolerated power levels were on average 600 W and, thus, slightly lower than those described in curative pelvic hyperthermia schedules. Eight out of 10 episodes of severe (WHO III degrees) toxicity represented typical side-effects of the chemotherapy given (nausea n = 4, diarrhoea n = 3, neuropathy n = 1). Two severe adverse events were firstly attributable to hyperthermia (haematuria, n = 1; deterioration of a decubital ulcer, n = 1). No patient suffered WHO-disease progression during the treatment period. Two patients achieved a partial remission. It is concluded that hyperthermic chemotherapy with oxaliplatin, folinic acid and 5-FU is feasible on an outpatient basis. Overall toxicity was moderate, although hyperthermia may add side-effects to this approach. Results, moreover, suggest a relevant palliative effect in patients with pre-irradiated pelvic recurrence of rectal cancer.