Submandibular gland extirpation during neck dissection, is it truly justified?

Background: There is no oncologic basis for the extirpation of the submandibular gland (SMG) in early oral squamous cell carcinomas (OSCC) unless the SMG is truly infiltrated by the tumor. The study aimed at assessing the true involvement of SMG in OSCC and to determine whether the gland extirpation in all cases is justified. Methods: This study prospectively evaluated the pathological involvement of SMG by OSCC in 281 patients, who were diagnosed with OSCC and underwent wide local excision of the primary tumor with simultaneous neck dissection. Results: Among 281 patients, 29 (10%) cases underwent bilateral neck dissection. A total of 310 SMG were evaluated. Involvement of SMG was seen in 5 (1.6%) cases. SMG metastases from Level Ib were seen in 3 (0.9%) of cases, whereas 0.6% showed direct SMG infiltration from the primary tumor. The advanced floor of mouth and lower alveolus cases had a higher tendency to infiltrate SMG. In none of the cases, bilateral or contralateral SMG was involved. Conclusion: The findings of this study show that the extirpation of SMG in all cases is truly irrational. Preserving the SMG is justified in early OSCC with no nodal metastasis. However, SMG preservation is case dependent and is an individual preference. Further studies are required to assess the locoregional control rate and salivary flow rate in postradiotherapy cases where SMG is preserved.

Assessment of Masticatory Function in Oral Cancer Patients with Mandibulectomy Followed by Pectoralis Major Myocutaneous Flap Reconstruction.

Mandibular resections have a dramatic effect on oral cavity functions. Ablative surgical defects are complex which are better reconstructed with free flaps. In developing countries like India, where majority of patients come from low socioeconomic status, pectoralis major myocutaneous flap is the most preferred reconstructive option. A retrospective questionnaire study was carried out to assess the mastication in patients with mandibulectomy followed by pectoralis major myocutaneous flap reconstruction. At the end of the study, it was observed that 86.6% of the patients had a good performance despite the lack of bony reconstruction. Thus, pectoralis major myocutaneous flap still stands strong in reconstructing large oral cavity defects.

Emission of bacterial bioaerosols from a composting facility in Maharashtra, India.

This study was undertaken to quantify and characterize size-segregated bacterial bioaerosols both on-site and off-site of a waste treatment facility (WTF) in Maharashtra employing windrow composting. Viable bacterial bioaerosols on nutrient agar (NA) and actinomycetes isolation agar (AIA) were quantified after sampling using Anderson-six stage impactor. Viable bacterial bioaerosols were identified based on 16S rDNA sequencing. Approximately, 16-34% of the total viable bacteria collected at the WTF were in the size range 0.65-2.1µm that can penetrate deep into the respiratory tract and also represents bacteria present in free form. Thus, 66-84% of bacterial bioaerosols were associated with coarse airborne particles greater than 2.1µm. A total of 24 bacterial species were isolated and characterized through gram staining. Among these 25% were gram negative and 75% were gram positive. The predominant bacterial genera were Bacillus, Streptococcus, Staphylococcus, Acinetobacter and Kocuria. The mean on-site concentration of total viable bacteria on NA and AIA and airborne particles (PM2.5 and PM10) were higher than the corresponding off-site values. The mean on-site concentration of viable bacteria on NA and AIA were in the range of 3.8×10(3) to 5.4×10(4)CFU/m(3) and 9.8×10(3) to 1.2×10(5)CFU/m(3), respectively, during activity period. Good correlation (R(2)=0.999) was observed between total bioaerosols and aerosols (PM10) collected using Anderson impactor and High volume sampler, respectively. Sampling size segregated aerosols using the Siotus personal cascade impactor indicated higher association of bacteria with the coarse fraction (greater than 2.5µm).

Vehicular pollution modeling using the operational street pollution model (OSPM) for Chembur, Mumbai (India).

Megacities in India such as Mumbai and Delhi are among the most polluted places in the world. In the present study, the widely used operational street pollution model (OSPM) is applied for assessing pollutant loads in the street canyons of Chembur, a suburban area just outside Mumbai city. Chembur is both industrialized and highly congested with vehicles. There are six major street canyons in this area, for which modeling has been carried out for NOx and particulate matter (PM). The vehicle emission factors for Indian cities have been developed by Automotive Research Association of India (ARAI) for PM, not specifically for PM10 or PM2.5. The model has been applied for 4 days of winter season and for the whole year to see the difference of effect of meteorology. The urban background concentrations have been obtained from an air quality monitoring station. Results have been compared with measured concentrations from the routine monitoring performed in Mumbai. NOx emissions originate mainly from vehicles which are ground-level sources and are emitting close to where people live. Therefore, those emissions are highly relevant. The modeled NOx concentration compared satisfactorily with observed data. However, this was not the case for PM, most likely because the emission inventory did not contain emission terms due to resuspended particulate matter.

Air quality mapping using GIS and economic evaluation of health impact for Mumbai City, India.

UNLABELLED: Mumbai, a highly populated city in India, has been selected for air quality mapping and assessment of health impact using monitored air quality data. Air quality monitoring networks in Mumbai are operated by National Environment Engineering Research Institute (NEERI), Maharashtra Pollution Control Board (MPCB), and Brihanmumbai Municipal Corporation (BMC). A monitoring station represents air quality at a particular location, while we need spatial variation for air quality management. Here, air quality monitored data of NEERI and BMC were spatially interpolated using various inbuilt interpolation techniques of ArcGIS. Inverse distance weighting (IDW), Kriging (spherical and Gaussian), and spline techniques have been applied for spatial interpolation for this study. The interpolated results of air pollutants sulfur dioxide (SO2), nitrogen dioxide (NO2) and suspended particulate matter (SPM) were compared with air quality data of MPCB in the same region. Comparison of results showed good agreement for predicted values using IDW and Kriging with observed data. Subsequently, health impact assessment of a ward was carried out based on total population of the ward and air quality monitored data within the ward. Finally, health cost within a ward was estimated on the basis of exposed population. This study helps to estimate the valuation of health damage due to air pollution. IMPLICATIONS: Operating more air quality monitoring stations for measurement of air quality is highly resource intensive in terms of time and cost. The appropriate spatial interpolation techniques can be used to estimate concentration where air quality monitoring stations are not available. Further, health impact assessment for the population of the city and estimation of economic cost of health damage due to ambient air quality can help to make rational control strategies for environmental management. The total health cost for Mumbai city for the year 2012, with a population of 12.4 million, was estimated as USD8000 million.

Assessment of changing patterns of Le fort fracture lines using computed tomography scan: an observational study.

OBJECTIVES: To assess the changing mid-face fracture patterns using a computed tomography scan. METHODOLOGY: Fifty patients with mid-face trauma requiring open reduction and fixation were studied using 1.6 mm axial, sagittal, coronal and 3D images. Images were evaluated clinically, intra-operatively and finally were compared with standard Le Fort lines. Results. The male population dominated the female at a ratio of 11.5:1. The majority of the mid-face fractures were seen in the age group of 21-30 years. Road traffic accident (78%) was the major etiological factor followed by work-related accidents (12%) and assaults (10%). The CT scan analysis included categorizing the patients into three groups: (1) Fracture patterns resembling Le Fort lines (24%); (2) Fracture patterns partially resembling Le Fort lines (56%); and (3) Fracture patterns that do not resemble Le Fort lines (20%). CONCLUSION: With the change in the velocity of wounding object, there is a change in the mid-face fracture patterns. The majority of the cases present as a variant of classical Le Fort fractures. Computed tomography is a valuable diagnostic tool in assessing the fractures of the mid-face. 2D images are more sensitive than 3D images. However, both the images are required in delivery of an optimal treatment plan.

Statistical analyses of coastal water quality for a port and harbour region in India.

A long-term study of temperature, pH, turbidity, suspended solid, salinity, dissolved oxygen, biochemical oxygen demand and ammonia nitrogen has been performed in a port and harbour region in India for four years from December 1996 to November 2000. Marine water quality results showed no regular trend. The mean monthly values of temperature, pH, turbidity, suspended solid, salinity, dissolved oxygen, biochemical oxygen demand and ammonia nitrogen were in the range of 22.64 +/- 0.4 to 29.05 +/- 1.37 degrees C; 7.65 +/- 0.04 to 7.81 +/- 0.13; 28.8 +/- 14.7 to 64.2 +/- 32.0 NTU; 283.5 +/- 81.8 to 356.0 +/- 159.7 mg/L; 29.78 +/- 7.18 to 29.78 +/- 1.04 ppt; 4.67 +/- 0.50 to 6.01 +/- 1.02 mg/L; 5.41 +/- 1.92 to 7.56 +/- 2.1 mg/L; and 0.25 +/- 0.07 to 0.63 +/- 0.49 mg/L, respectively. The results of correlation analysis showed that biochemical oxygen demand (BOD) was inversely correlated dissolved oxygen (DO) and poorly correlated with all other parameters. Turbidity and suspended solid were moderately correlated with each other while salinity was moderately correlated with other water quality parameters. In factor analysis, four factors were drawn out of the eight variables, which represented 74% of the variance of the original data. Factor I was related to suspended solid and turbidity. Factor II represented mainly temperature and DO showing inverse relation between these two. Factor III implied the degree of pollution at any monitoring station. Factor IV included pH and salinity. It could be concluded that the factor model represented almost all the variables.

A long-term study of oxides of nitrogen, sulphur dioxide, and ammonia for a port and harbor region in India.

A long-term study of oxides of nitrogen (NOx), sulphur dioxide (SO2), and ammonia (NH3) has been performed in a port and harbor region in India from January 1997 to December 2000. Meteorological data was also collected to establish the correlation with gaseous pollutants concentrations. Monthly mean concentrations of NOx were in the range of 19.5-59.0 microg/m3 and were observed to be highest during winter season. Monthly mean concentrations of SO2 were in the range of 8.6-51.3 microg/m3 and were observed to be highest during winter season. The concentrations of SO2 increased gradually from 18.8 microg/m3 in 1997 to 33.3 microg/m3 in 2000. This may be attributed to the increase in port activities and ship traffic, which had an annual growth of about 15%. Monthly mean concentrations of NH3 were in the range of 87.1-235.1 microg/m3 and the maximum concentration was observed during post-monsoon season. It may be concluded that NOx and SO2 have their maximum values during winter season while NH3 has a maximum value during post-monsoon season. Statistical analysis was carried out for air pollutant data for the period 1997-2000 and correlation between gaseous pollutants (NOx, SO2, NH3) and meteorological parameters (temperature and wind speed) was estimated. NH3 was found to be weakly correlated with NOx (0.46), strongly correlated with SO2 (0.75) and negatively correlated with wind speed (-0.60). The highest correlation (0.87) was observed between SO2 and NOx because of common sources. A strong negative correlation was found between wind speed and gaseous pollutants. The above finding is also supported by monitoring results that when the wind velocity doubled, the concentrations of pollutants decreased sharply to about a half. Regression analysis showed that relationship among NOx, SO2, wind speed, and temperature was moderate to strong while that among NH3, wind speed, and temperature was poor. Hence regression equations could be developed for predicting NOx and SO2 concentrations.

A comparison of water quality indices for coastal water.

The present article discusses and compares five different water quality indices, viz arithmetic water quality index, multiplicative water quality index, unweighted arithmetic water quality index, unweighted multiplicative water quality index, and Harkin's water quality index, which were considered for characterizing the coastal water quality at the Jawaharlal Nehru Port Trust, Bombay, India. Dissolved oxygen, pH, biochemical oxygen demand (BOD), temperature, suspended solid, and turbidity were used as the parameters of water quality indices. The value function graphs used for above-mentioned variables were developed using harbour water quality standards and aquatic life. The product moment correlation coefficients for various water quality indices were determined using the SPSS software package to evaluate correlation among various indices. It was found that the unweighted arithmetic water quality index was higher than weighted arithmetic water quality index while the multiplicative water quality index was lower than unweighted multiplicative water quality index. All the indices were well correlated with each other except Harkin's water quality index. The Harkin's water quality index was different from other water quality indices. The comparison of different form of indices showed that the multiplicative water quality index was the most suitable water quality index for coastal waters.