Assessment of cross-sectional thickness and activity of masseter, anterior temporalis and orbicularis oris muscles in oral submucous fibrosis patients and healthy controls: an ultrasonography and electromyography study.

OBJECTIVES: Oral submucous fibrosis (OSMF) is an insidious chronic disease that is associated with significant functional morbidity and an increased risk for malignancy. It initially affects the lamina propria of the oral mucosa, and, as the disease progresses, it involves the submucosa and deeper tissue, including muscles of the oral cavity, resulting in loss of fibroelasticity. OSMF is a pre-malignant condition mainly caused by areca nut chewing. The aim of this study was to find out the involvement of muscles of mastication and facial expression in patients with OSMF by assessing the cross-sectional thickness and activity of the masseter, anterior temporalis and orbicularis oris muscles by ultrasonography and electromyography and comparing with healthy controls and also to find out any correlation between the ultrasonographic cross-sectional thicknesses of the masseter, anterior temporalis and orbicularis oris muscles with electromyographic activity. METHODS: 40 patients with OSMF were included in the study group, and the patients were divided into four groups on the basis of interincisal mouth opening, i.e. Group I (mouth opening >35 mm), Group II (mouth opening between 30 and 35 mm), Group III (mouth opening between 20 and 30 mm) and Group IV (mouth opening <20 mm). Ultrasonographic cross-sectional thickness and electromyographic activity (amplitude and duration) of the masseter, anterior temporalis and orbicualris oris muscles were recorded in patients with OSMF and 20 controls. Intergroup comparison of ultrasonographic cross-sectional thickness and activity (amplitude and duration) was done, and Pearson's correlation coefficient was applied to find out any relation between ultrasonographic and electromyographic findings. RESULTS: Thickness and activity of the masseter muscle was significantly reduced in Group IV (mouth opening <20 mm) when compared with the control group. The anterior temporalis and orbicularis oris muscles remained unaffected. A positive correlation was observed between the thicknesses of the masseter muscle and the amplitude in Groups I, II and III; the anterior temporalis muscle in Group II and the control group; and the orbicularis oris muscle in Groups II, III and IV. CONCLUSIONS: It was concluded that, among the muscles studied, there was an early involvement of the masseter muscle in patients with OSMF compared with that of other muscles.

Assessment of performance and utility of mortality prediction models in a single Indian mixed tertiary intensive care unit.

OBJECTIVES: To assess the performance and utility of two mortality prediction models viz. Acute Physiology and Chronic Health Evaluation II (APACHE II) and Simplified Acute Physiology Score II (SAPS II) in a single Indian mixed tertiary intensive care unit (ICU). Secondary objectives were bench-marking and setting a base line for research. MATERIALS AND METHODS: In this observational cohort, data needed for calculation of both scores were prospectively collected for all consecutive admissions to 28-bedded ICU in the year 2011. After excluding readmissions, discharges within 24 h and age <18 years, the records of 1543 patients were analyzed using appropriate statistical methods. RESULTS: Both models overpredicted mortality in this cohort [standardized mortality ratio (SMR) 0.88 ± 0.05 and 0.95 ± 0.06 using APACHE II and SAPS II respectively]. Patterns of predicted mortality had strong association with true mortality (R (2) = 0.98 for APACHE II and R (2) = 0.99 for SAPS II). Both models performed poorly in formal Hosmer-Lemeshow goodness-of-fit testing (Chi-square = 12.8 (P = 0.03) for APACHE II, Chi-square = 26.6 (P = 0.001) for SAPS II) but showed good discrimination (area under receiver operating characteristic curve 0.86 ± 0.013 SE (P < 0.001) and 0.83 ± 0.013 SE (P < 0.001) for APACHE II and SAPS II, respectively). There were wide variations in SMRs calculated for subgroups based on International Classification of Disease, 10(th) edition (standard deviation ± 0.27 for APACHE II and 0.30 for SAPS II). INTERPRETATION AND CONCLUSION: Lack of fit of data to the models and wide variation in SMRs in subgroups put a limitation on utility of these models as tools for assessing quality of care and comparing performances of different units without customization. Considering comparable performance and simplicity of use, efforts should be made to adapt SAPS II.

Biomonitoring of heavy metals by pollen in urban environment.

Abstract Industrial development and consumption of petroleum products leads to increase air pollution levels especially in urban and industrial areas. Heavy metal components associated with air pollutants have far reaching effects with respect to economic and ecological importance of pollens. The pollens are male reproductive organs of the plant and travel through air from flower to flower for pollination purpose. During this period they are exposed to air pollutants. Present investigation thus pertains to study of effect of air pollutants on pollens especially biosorption and bioaccumulation of heavy metals. The pollens of three commonly occurring plants namely Cassia siamea, Cyperus rotundus, Kigelia pinnata have been studied from the NH-6 of Nagpur city, India. The pollens exposed to polluted air showed the presence of higher concentrations of Ca, Al and Fe as compared to unexposed pollens. Higher concentration of these metals was observed in Cyperus rotundus followed by Cassia siamea and Kigelia pinnata. These results indicate that pollens act as good indicator of air pollution giving results in short time of exposure of 5-10 h. Apart from this, it is also reported that some of these metals play crucial role in the metabolic activity in pollens for example Calcium is necessary for growth of pollen tube and other metabolic activities in pollens. The presence of these metals in pollens may also enhance the allergenicity of the pollens. Similarly accumulation of heavy metals may also deteriorate the quality of pollen for their economical use. The viability of pollen is also affected by these pollutants in sensitive species leading to impairment of their fertility.

Determination of rifampicin and its main metabolite in plasma and urine in presence of pyrazinamide and isoniazid by HPLC method.

A reversed phase HPLC method is described for the simultaneous estimation of rifampicin and its major metabolite desacetyl rifampicin, in the presence of isoniazid and pyrazinamide, in human plasma and urine. The assay involves simple liquid extraction of drug, metabolite and internal standard (rifapentine) from biological specimens and their subsequent separation on a C18 reversed phase column and single wavelength UV detection. In plasma as well as in urine samples, all the three compounds of interest eluted within 17 min. Using methanol-sodium phosphate buffer (pH 5.2; 0.01 M) (65:35, v/v) as mobile phase under isocratic conditions, it was established that isoniazid, pyrazinamide and ascorbic acid (added to prevent oxidative degradation of analytes) did not interfere with the analyte peaks. Recoveries (extraction efficiency) for drug were greater than 90% in both plasma and urine, whereas for metabolite the values were found to be 79 and 86% in plasma and urine, respectively. The plasma and urine methods were precise (total coefficient of variation ranged from 5 to 23%) and accurate (-7 to 5% of the nominal values) for both the analytes. Individual variance components, their estimates and their contribution to the total variance were also determined. Using the same method, unknown samples supplied by WHO were assayed and good correlations were obtained between the found and intended values. The method developed proved to be suitable for simultaneous estimation of rifampicin and desacetyl rifampicin in plasma and urine samples.

Improving dose homogeneity in routine head and neck radiotherapy with custom 3-D compensation.

BACKGROUND AND PURPOSE: Anatomic contour irregularity and tissue inhomogeneity can lead to significant radiation dose variation across the complex treatment volumes found in the head and neck (H&N) region. This dose inhomogeneity can routinely create focal hot or cold spots of 10-20% despite beam shaping with blocks or beam modification with wedges. Since 1992, we have implemented the routine use of 3-D custom tissue compensators fabricated directly from CT scan contour data obtained in the treatment position in order to improve dose uniformity in patients with tumors of the H&N. MATERIALS AND METHODS: Between July 1992 and January 1997, 160 patients receiving comprehensive H&N radiotherapy had 3-D custom compensators fabricated for their treatment course. Detailed dosimetric records have been analyzed for 30 cases. Dose uniformity across the treatment volume and clinically relevant maximum doses to selected anatomic sub-sites were examined with custom-compensated, uncompensated and optimally-wedged plans. RESULTS: The use of 3-D custom compensators resulted in an average reduction of dose variance across the treatment volume from 19+/-4% for the uncompensated plans to 5+/-2% with the use of 3-D compensators. Optimally-wedged plans were variable, but on average a 10+/-3% dose variance was noted. For comprehensive H&N treatment which encompassed the larynx within the primary field design, the peak doses delivered were reduced by 5-15% with 3-D custom compensation as compared to optimal wedging. CONCLUSIONS: The use of 3-D custom tissue compensation can improve dose homogeneity within the treatment volume for H&N cancer patients. Maximum doses to clinically important structures which often receive greater than 105-110% of the prescribed dose are routinely reduced with the use of 3-D custom compensators. Improved dose uniformity across the treatment volume can reduce normal tissue complication profiles and potentially allow for delivery of higher total doses in an attempt to enhance locoregional tumor control.

Damage-sensing mechanisms in human cells after ionizing radiation.

Human cells have evolved several mechanisms for responding to damage created by ionizing radiation. Some of these responses involve the activation or suppression of the transcriptional machinery. Other responses involve the downregulation of enzymes, such as topoisomerase I, which appear to be necessary for DNA repair or apoptosis. Over the past five years, many studies have established links between DNA damage, activation of transcription factors that are coupled to DNA repair mechanisms, increased gene transcription and altered cell cycle regulation to allow for repair or cell death via apoptosis or necrosis. Together these factors determine whether a cell will survive with or without carcinogenic consequences. The immediate responses of human cells to ionizing radiation, in terms of sensing and responding to damage, are therefore, critical determinants of cell survival and carcinogenesis.

Adjuvant radiation versus observation: a cost analysis of alternate management schemes in early-stage testicular seminoma.

PURPOSE: This study was designed to compare costs of adjuvant radiation versus observation in the management of early-stage testicular seminoma after inguinal orchiectomy. MATERIALS AND METHODS: A line-by-line inspection of the charges generated during a course of adjuvant pelvic and paraaortic radiotherapy and of three cycles of bleomycin, etoposide, and platinum salvage chemotherapy was performed for five patients who received irradiation and five patients who received salvage chemotherapy. The average charge for either treatment was then calculated. Only those charges directly associated with the diagnosis of seminoma were included in the analysis. Follow-up charges were also generated from the patients' billing records. The optimum follow-up regimen for either management option was derived from a synthesis of the international literature. A 5% rate of failure was assumed if adjuvant irradiation was administered, and a 15% rate of failure was assumed if observation was the option chosen. Charges were truncated at 5 years. RESULTS: The total charge generated over 5 years based on following a policy of observation is $27,223 per patient versus $19,557 if the option of adjuvant irradiation in chosen. Using University of Wisconsin institutional reimbursement rates, the estimated costs were $20,487 and $14,722 for the option of observation and adjuvant radiation, respectively. The cost equivalence point between the two options occurs at 2.5 years, when the initial cost of adjuvant radiotherapy is matched by the cost generated during the period of observation. The maximum cost difference is achieved by 5 years. CONCLUSION: Following a policy of observation postorchiectomy for early-stage testicular seminoma generates 39% more medical costs per patient over a 5-year follow-up period than does following the standard policy of adjuvant irradiation to the pelvic and paraaortic regions, with no reported difference in outcome.

Role of circulating immune complexes and platelet aggregation in the development of experimentally induced atherosclerosis in monkeys with normal intact vas deferens and following vasectomy.

The study was undertaken in normal and vasectomized monkeys to elucidate the relationship of circulating immune complexes and platelet aggregability with experimental aortic and coronary atherosclerosis. Four groups of animals, viz. sham-vasectomized stock diet fed, vasectomized stock diet fed, sham-vasectomized atherogenic diet fed, were studied for a period of 1 year. An increased incidence of atherosclerosis was noted with high levels of circulating immune complexes in vasectomized monkeys. Platelets obtained from atherogenic diet fed monkeys had a clear tendency of increased aggregation and agglutination in the presence of ADP, epinephrine and ristocetin respectively. Vasectomy produced a significant enhancement in platelet aggregation response with ADP and epinephrine in atherogenic diet fed animals. The aortic and coronary atherosclerosis was also significantly increased in atherogenic diet fed groups both with and without vasectomy.

Effect of vasectomy on serum lipids, platelet aggregability and development of ischaemic heart disease in rhesus monkeys.

In this study the long term effects of vasectomy on serum lipid profile, in vitro platelet aggregability and the risk of developing acute myocardial infarction have been elucidated in a monkey model. Four groups were made viz. (I) atherogenic diet fed vasectomised, (II) atherogenic diet fed control, (III) stock diet fed vasectomised and (IV) stock diet fed control. The respective diets were fed for first 6 months and then half of the atherogenic and stock diet fed monkeys were bilaterally vasectomised. The remaining monkeys were sham-vasectomised. At the end of one year, norepinephrine infusion was given to all the monkeys each day for 2 hrs, for 3 consecutive days and animals sacrificed after 96 hrs. Although serum lipids were not altered following vasectomy, platelet aggregation response was significantly enhanced in atherogenic diet fed animals. ECG changes were suggestive of acute myocardial ischaemia in 4 monkeys, 2 each from gp. I and II. Histopathology of heart revealed patchy myocardial necrosis and haemorrhage only in one monkey of gp. I, while others had fuchsinorrhagia indicating ischaemic change. These findings are in contrast to those seen in vasectomised human subjects.