Influence of enzyme activity on domestic wastewater amelioration in a hybrid subsurface flow constructed wetland.

Wastewater treatment in a constructed wetland is achieved by the presence of plant species, the metabolism of microorganisms, and the enzyme activities. Three small-scale hybrid subsurface flow constructed wetlands (HSFCWs) planted with Arundo donax and one unplanted HSFCW were constructed near a water resource recovery facility at Guru Gobind Singh Indraprastha University. The purpose of the study was to determine the correlation between soil enzymatic activities and the removal of contaminants from domestic wastewater. Enzyme activity of phosphatase, protease, urease, and cellulase increased with an increase in temperature. A strong correlation between enzyme activities and TKN and surfactant removal was observed, whereas moderate correlation was observed with phosphate in planted HSFCW during the study. The correlation between COD removal and enzyme activities was low to moderate. In unplanted HSFCW, the correlation between enzyme activities and COD removal was negative, negligible to moderate to strong in the case of TKN, low to moderate in the case of phosphate, and negligible to low in the case of surfactants. The increased removal efficiency of the planted system compared with that of the unplanted system indicated a positive impact on enzyme activities with the growth of plants and their roots. PRACTITIONER POINTS: Protease, urease, and cellulase activities: Planted HSFCW exhibited higher protease, urease, and cellulase activities than unplanted, signifying enhanced breakdown. July displayed maximum enzyme activities, correlating with heightened biological breakdown in both systems. Fluctuations in enzyme activities reflected seasonal changes, influencing nutrient degradation rates. Planted HSFCW consistently showed higher enzymatic activities across protease, urease, and cellulase than unplanted.

Anti-malarial property of steroidal alkaloid conessine isolated from the bark of Holarrhena antidysenterica.

BACKGROUND: In the face of chronic and emerging resistance of parasites to currently available drugs and constant need for new anti-malarials, natural plant products have been the bastion of anti-malarials for thousands of years. Moreover natural plant products and their derivatives have traditionally been a common source of drugs, and represent more than 30% of the current pharmaceutical market. The present study shows evaluation of anti-malarial effects of compound conessine isolated from plant Holarrhena antidysenterica frequently used against malaria in the Garhwal region of north-west Himalaya. METHODS: In vitro anti-plasmodial activity of compound was assessed using schizont maturation and parasite lactate dehydrogenase (pLDH) assay. Cytotoxic activities of the examined compound were determined on L-6 cells of rat skeletal muscle myoblast. The four-day test for anti-malarial activity against a chloroquine-sensitive Plasmodium berghei NK65 strain in BALB/c mice was used for monitoring in vivo activity of compound. In liver and kidney function test, the activity of alkaline phosphatase (ALP) was examined by p-NPP method, bilirubin by Jendrassik and Grof method. The urea percentage was determined by modified Berthelot method and creatinine by alkaline picrate method in serum of mice using ENZOPAK/CHEMPAK reagent kits. RESULTS: Compound conessine showed in vitro anti-plasmodial activity with its IC50 value 1.9 µg/ml and 1.3 µg/ml using schizont maturation and pLDH assay respectively. The compound showed cytotoxity IC50= 14 µg/ml against L6 cells of rat skeletal muscle myoblast. The isolated compound from plant H. antidysenterica significantly reduced parasitaemia (at 10 mg/kg exhibited 88.95% parasite inhibition) in P. berghei-infected mice. Due to slightly toxic nature (cytotoxicity = 14), biochemical analysis (liver and kidney function test) of the serum from mice after administration of conessine were also observed. CONCLUSION: The present investigation demonstrates that the compound conessine exhibited substantial anti-malarial property. The isolated compound could be chemically modified to obtain a more potent chemical entity with improved characteristics against malaria.

Network interactions with functional roles and evolutionary relationships for BURP domain-containing proteins in chickpea and model species.

The functional significance and evolutionary relationships of BURP domain-containing genes unique to plants is of interest. Network analysis reveals different associations of BURP proteins with other proteins and functional terms, throwing light on their involvement in various biological processes and pathways. The gene expression data reveals that BURP genes are affected by salinity stress, reflecting diverse expression patterns in roots and shoots.

Comprehensive study on impact assessment of lockdown on overall ambient air quality amid COVID-19 in Delhi and its NCR, India.

Indian government announced the complete lockdown from 25 March, 2020 for all outdoor activities across the country due to containment of COVID-19. This study is an attempt to assess the impacts of lockdown on ambient air quality in five cities of Indian National Capital Region including Delhi, Gurugram, Noida, Ghaziabad and Faridabad. In this context, the data of air pollutants (PM10, PM2.5, NOx, NO, NO2, SO2, NH3, SO2, CO, and C6H6) from 36 locations of the study area were analyzed from 1st March to 1st May, 2020. The results showed that PM10 and PM2.5 level decreased upto 55-65 %. NOx and NO have shown maximum reduction (∼ 50-78 %). Similarly, consistent and significant reduction in other air pollutants such as SO2 (∼33 %), CO (∼45 %), NH3 (∼27 %) and C6H6 (∼53 %) has been observed. During lockdown Air Quality Index (AQI) shows improvement as its value significantly decreased (∼ 45 %-68 %). An interesting feature observed that during first week of lockdown O3 decreased but later it increased by ∼19-27%. The study suggests that this pandemic gives lessons for interventions for urban air pollution mitigation in controlling the health impact due to urban air pollution.

The Great Smog Month and Spatial and Monthly Variation in Air Quality in Ambient Air in Delhi, India.

BACKGROUND: In recent years, poor urban air quality in Delhi, India has gained significant attention. Episodic events including crop stubble burning and Diwali celebrations are considered major factors in the worsening quality of ambient air. OBJECTIVE: This study aimed to investigate spatial and monthly variation as well as the role of episodic events in ambient air quality in Delhi, including the 'Great Smog' month of November 2017. METHODS: Monitoring of air pollutants (particulate matter (PM10, PM2.5, PM1) and nitrogen dioxide (NO2)) was carried out at three distinct locations of Delhi from April 2017-February 2018. The concentration of NO2 was measured using a modified Jacob and Hochheiser method and PM was measured using a GRIMM aerosol spectrometer. Air quality index was also determined to identify the effects of air pollution on human health. RESULTS: Overall, the levels of air pollution were found to be approximately 2.1-3.2 times higher along a traffic intersection and about 1.4-2.0 times higher in a commercial area compared with an institutional area. The highest average monthly concentrations of PM10, PM2.5, PM1 and NO2 were 768, 374, 298 and 149 µg/m3, respectively, during the Great Smog month of November 2017. November and August were recorded as the most polluted and cleanest months, respectively, in the city. Generally, poor to severe categories of the air quality index (AQI) were obtained from October to February. Higher concentrations during November were attributed to stubble burning in the nearby states of Delhi with the additive effect of fireworks during Diwali celebrations. CONCLUSIONS: Severe ambient air quality as observed in the present study is a serious matter of concern for the health of Delhi's population. To control spikes in poor air quality during episodic events, it is imperative to raise awareness among farmers regarding the severe health hazards of stubble burning. COMPETING INTERESTS: The authors declare no competing financial interests.

Plasmodium falciparum gametocytaemia with chloroquine chemotherapy in persistent malaria in an endemic area of India.

BACKGROUND & OBJECTIVE: Gametocyte sex-ratio in Plasmodium falciparum malaria is an important determinant of transmission success and basis of disease epidemiology. Information on ratio of male to female gametocytes after an exposure of antimalarial regimens under field conditions is very limited. In this retrospective study we observed high densities of gametocytes along with high sex-ratio in P. falciparum cases, which may be responsible for persistent malaria transmission in this area. METHODS: Laksar PHC of Hardwar district, Uttarakhand State, India was selected because it contributed 90 per cent of the total malaria cases. A total of 568 uncomplicated P. falciparum malaria patients were assessed to investigate prevalence of gametocytes while 339 P. falciparum thick smears containing 5620 gametocytes were screened for measuring the gametocyte density for microgametocyte (male) and macrogametocyte (female). Homology of variance ('F' test) was checked on days 7 and 14 including the variables and risk factors namely fever, parasitaemia, gametocyte carriage in sensitive and resistant chloroquine treated P. falciparum cases. RESULTS: Slide positivity rate (SPR) increased drastically from 0.23 to 11.4 per cent with the predominance in P. falciparum infection after 1998. All 568 cases showed gametocytes in their peripheral blood, of which 109 (19%) were infected with rings and gametocytes and 459 (81%) had gametocytes stages in their peripheral blood while 422 (74.3%) cases were infected with ring stages only. Of the 339 P. falciparum positive blood smears, 5620 gametocytes were screened for their sex-ratio. The mean sex-ratio was 0.31 (3.22 female per male). Prevalence of gametocytaemia was significantly higher (P<0.05) in chloroquine (CQ)- resistant than in CQ-sensitive patients with days 7 and 14 follow up. The homology of variance with risk factors for gametocytes on days 7 and 14 were highly significant (P<0.001) in the study period but during the post-exposure period of days 3 and 5, these were insignificantly correlated. INTERPRETATION & CONCLUSION: A high density of P. falciparum gametocytes was observed at the time of preparation of blood slide on day 0. Improper chloroquine treatment along with poor patient compliance for radical treatment and the presence of chloroquine resistant P. falciparum malaria may have enhanced the prevalence and density of P. falciparum gametocytes which was instrumental in signaling the persistent malaria in this area.

Primary non-Hodgkin lymphoma of liver.

Primary non-Hodgkin lymphoma (NHL) of liver is a very rare malignancy. Here, we report the case of a 65-year-old man who presented with constipation and right groin pain of 2 months' duration. A computed tomography (CT) scan of the abdomen incidentally detected multiple hypodense nodules in both lobes of the liver. Diagnosis of primary NHL of liver was made using ultrasound-guided biopsy. Extensive investigations--which included bone marrow biopsy; fluorescence in situ hybridization; flow cytometry; CT scan of chest, abdomen, and pelvis; and whole-body positron-emission tomography--showed no involvement of bone marrow, lymph nodes, spleen, or any other organ. The patient is currently being treated with a CHOP-R (cyclophosphamide-doxorubicin-vincristine-prednisolone/rituximab) regimen. The case has many unique features, including normal liver function tests, especially that for lactate dehydrogenase; no type B symptoms; and negative serology for viruses. The case demonstrates that primary hepatic lymphoma should be considered in the differential diagnosis of space-occupying liver lesions in presence of normal levels of alpha-fetoprotein and carcinoembryonic antigen. The literature is extensively reviewed.

A comprehensive study on spatio-temporal distribution, health risk assessment and ozone formation potential of BTEX emissions in ambient air of Delhi, India.

The hazardous air pollutants like benzene, toluene, ethylbenzene and xylene (BTEX) are considered as toxic because of their role in ozone formation and adverse effects on human health. Owing to this, the present study was carried out at six spatially distributed sites in Delhi from November 2017- June 2018. Activated charcoal tubes were used to collect samples of BTEX and were further analyzed using GC-FID. The minimum BTEX concentration was found at institutional site (9.94 µg/m3) and maximum at roadside site (103.12 µg/m3) with the average of 46.66 µg/m3. Also, the levels of BTEX were 1.18-1.74 times higher during rush hours as compared to non-rush hours. The high T/B ratio (2.26-3.41) observed is the indication of the traffic-originated sources of emission. The cancer risks calculated for benzene at probability 0.50 ranged as 1.29E-06 - 1.80E-05, whereas 4.09E-06 - 3.40E-05 at probability 0.95, which were higher than the acceptable value of 1.0E-06. The non-cancer health risks in terms of hazard index were observed less than unity i.e. within acceptable limit. The total ozone formation potential (OFP) was obtained as 207.51 ±â€¯123.40 µg/m3 with maximum potential by toluene. Such high levels of BTEX, cancer risks and OFP obtained in the study especially at roadside and connectivity hub are harmful for people residing near these areas, and also to large commuters, who are exposed to such emissions during travelling.

Impact of biomass fuel exposure from traditional stoves on lung functions in adult women of a rural Indian village.

INTRODUCTION: Exposure to biomass fuel (BMF) from traditional cookstoves inflicts an enormous burden of morbidities in women across the developing world. This study aims to assess the lung function and its association with the indoor air pollutants generated using BMF. MATERIALS AND METHODS: This cross-sectional study including 310 women was conducted in a rural village of India. Households were divided into two groups based on the cooking fuel, the BMF group and the liquefied petroleum gas (LPG) group. Information on respiratory symptoms and socioeconomic status was obtained using a standard questionnaire. Indoor air concentration for PM10and PM2.5was measured during cooking hours. Pulmonary function tests (PFTs) were conducted for the women inhabitants. RESULTS: On comparing the two groups, the concentration of PM10(890.26 ± 59.59 vs. 148.66 ± 31.97) µg/m3 and PM2.5(728.90 ± 50.20 vs. 99.76 ± 41.80) µg/m3 (P < 0.01) were higher in the group using BMF. The respiratory symptoms such as wheezing, dyspnea, chronic cough, and nocturnal cough, were significantly more common in the group using BMF. A significant difference was seen in the lung function indices between the two groups. A significant negative correlation of respiratory indices with duration of exposure and the particulate matter (PM) values suggested a greater decline on lung function among women exposed to increased concentrations of PM. On comparing participants with normal and abnormal PFT, it was seen that the use of BMF (odds ratio [OR] 8.01; 95% confidence interval [CI] 4.80, 13.36, P < 0.001) and the duration of exposure to BMF (OR 1.16; 95% CI 1.13, 1.20., P < 0.001) increased the odds of having an abnormal PFT. CONCLUSIONS: This study shows a high prevalence of respiratory symptoms and an abnormal pulmonary function in women exposed to BMF.

High-performance liquid chromatographic assay for the determination of sulfadoxine and N-acetyl sulfadoxine in plasma from patients infected with sensitive and resistant Plasmodium falciparum malaria.

A reversed-phase high-performance liquid chromatographic method using a mobile phase of acetonitrile-methanol-trifluoroacetic acid-water (16.1:7.2:0.1:76.6, v/v/v/v) at a flow rate of 1.0 ml min(-1) on a LiChrospher RP-18 column with UV (254 nm) detection has been developed for the separation of sulfadoxine and its metabolite N-acetyl sulfadoxine in plasma. No interferences due to endogenous compounds or common antimalarial drugs were noticed. The limit of detection for sulfadoxine and N-acetyl sulfadoxine was 0.01 microg ml(-1) with a signal-to-noise ratio of 5:1 while the limit of quantification was 2.5 microg ml(-1). Intra-day mean relative standard deviations (RSD's) for sulfadoxine and N-acetyl sulfadoxine were 2.6 and 2.8%, respectively, while mean inter-day RSD's for sulfadoxine and N-acetyl sulfadoxine were 2.4 and 2.8%, respectively. Extraction recoveries averaged 90.6% for sulfadoxine and 86.9% for N-acetyl sulfadoxine. The method was applied for the assay of sulfadoxine and its metabolite N-acetyl sulfadoxine in plasma from Plasmodium falciparum malaria patients. Mean plasma sulfadoxine concentrations on day 2 (51 h) from samples collected from sensitive and resistant P. falciparum patients treated with three tablets of Fansidar were 62.8 and 60.5 microg ml(-1), respectively. Mean ratio of N-acetyl sulfadoxine to sulfadoxine was 9.1% for responders and 13.9% for non-responders which revealed that higher amounts of the metabolite N-acetyl sulfadoxine were present in non-responders. The method described should find an application in the therapeutic monitoring of malaria patients.

Isolation and characterization of microsomal omega-6-desaturase gene (fad2-1) from soybean.

A genomic DNA sequence (fad2-1) encoding seed specific microsomal 0-6 desaturase was isolated from soybean (Glycine max. L cv. Pusa-9702). A positive genomic clone of 1852 nucleotides containing a single uninterrupted 3' end exonic region with an ORF of 1140 bp encoding a peptide of 379 amino acids, a complete 3' UTR of 206 bp and 86 bp of 5' UTR interrupted by a single intron of 420 bp was obtained on screening the sub-genomic library of soybean. Southern blots revealed at least two copies of the gene per haploid genome. Analysis of the translated product showed the presence of three histidine boxes, with the general sequence HXXXH and five probable transmembrane segments reported to be involved in substrate specificity.

Commuter exposure to inhalable, thoracic and alveolic particles in various transportation modes in Delhi.

A public health concern is to understand the linkages between specific pollution sources and adverse health impacts. Commuting can be viewed as one of the significant-exposure activity in high-vehicle density areas. This paper investigates the commuter exposure to inhalable, thoracic and alveolic particles in various transportation modes in Delhi, India. Air pollution levels are significantly contributed by automobile exhaust and also in-vehicle exposure can be higher sometime than ambient levels. Motorcycle, auto rickshaw, car and bus were selected to study particles concentration along two routes in Delhi between Kashmere Gate and Dwarka. The bus and auto rickshaw were running on compressed natural gas (CNG) while the car and motorcycle were operated on gasoline fuel. Aerosol spectrometer was employed to measure inhalable, thoracic and alveolic particles during morning and evening rush hours for five weekdays. From the study, we observed that the concentration levels of these particles were greatly influenced by transportation modes. Concentrations of inhalable particles were found higher during morning in auto rickshaw (332.81 ± 90.97 µg/m(3)) while the commuter of bus exhibited higher exposure of thoracic particles (292.23 ± 110.45 µg/m(3)) and car commuters were exposed to maximum concentrations of alveolic particles (222.37 ± 26.56 µg/m(3)). We observed that in evening car commuters experienced maximum concentrations of all sizes of particles among the four commuting modes. Interestingly, motorcycle commuters were exposed to lower levels of inhalable and thoracic particles during morning and evening hours as compared to other modes of transport. The mean values were found greater than the median values for all the modes of transport suggesting that positive skewed distributions are characteristics of naturally occurring phenomenon.

Comparison of adenosine and exercise thallium-201 single-photon emission computed tomography (SPECT) myocardial perfusion imaging. The GE SPECT Multicenter Adenosine Study Group.

Pharmacologic stress with dipyridamole has provided useful diagnostic, as well as prognostic, information in patients undergoing thallium-201 myocardial perfusion imaging. With its ultrashort half-life and a potent and consistent vasodilator effect, adenosine may be the coronary vasodilator of choice with myocardial perfusion imaging. Fifty-one healthy subjects and 93 patients with suspected coronary artery disease constituted the study group. In this multicenter study the comparative safety and diagnostic efficacy of single-photon emission computed tomography (SPECT) thallium imaging during adenosine-induced coronary hyperemia was compared with exercise treadmill stress. There was a mean increase in heart rate of 37% and a mean decrease in diastolic blood pressure of 5% during the adenosine infusion of 140 micrograms/kg per min for 6 min. Adenosine infusion was well tolerated in 95% of the subjects. Side effects requiring intervention occurred in seven subjects (5%). None of the subjects experienced a life-threatening complication. The sensitivity, specificity and predictive accuracy for detection of coronary artery disease with use of quantitative analysis was 83%, 87% and 84% for adenosine SPECT and 82%, 80% and 81% for exercise SPECT studies, respectively. Most false negative results with adenosine, as well as exercise SPECT studies, occurred in patients with single-vessel disease. The first-order concordance (no defect vs. defect) and second-order concordance (no defect vs. irreversible vs. reversible defect) was 89% and 78% between the two studies, respectively. Thus, the results of adenosine SPECT imaging are highly concordant with exercise SPECT thallium imaging. Adenosine SPECT thallium imaging provides a safe and highly accurate imaging mode for the detection of coronary artery disease.

Probability of malignancy in solitary pulmonary nodules using fluorine-18-FDG and PET.

UNLABELLED: Nearly one-third of solitary pulmonary nodules are radiographically indeterminate for the presence of malignancy. METHODS: FDG-PET imaging was used to differentiate benign and malignant solitary pulmonary nodules in 61 patients with radiographically indeterminate nodules. After confirmation of the histological diagnosis, the probability for cancer was established for positive and negative PET scans and compared to the risk estimates calculated using other patient variables. RESULTS: FDG-PET had a sensitivity, specificity and positive predictive value of 93%, 88% and 92%, respectively, for detecting malignancy in indeterminate solitary pulmonary nodules. The probability of malignancy with a positive PET scan is 83%, which increases with the patient's age (90% in >60 yr) and the size of the nodule. A negative PET scan is associated with only a 4.7% risk of malignancy. FDG-PET also accurately characterized hilar/mediastinal lymphadenopathy in 12 patients with associated lymph node lesions. CONCLUSION: FDG-PET imaging can be a useful noninvasive test to determine the risk estimate or probability of cancer as well as preoperative staging in patients with radiographically indeterminate solitary pulmonary nodules.

Standardized uptake values of FDG: body surface area correction is preferable to body weight correction.

UNLABELLED: Standardized uptake values (SUVs) are widely used to measure 18F-fluorodeoxyglucose (FDG) uptake in various tumors. It has been reported that normalization of FDG uptake for patient body weight (SUVbw) overestimates FDG uptake in heavy patients, as their fraction of body fat (with low FDG uptake) is often increased. The objective of this study was to determine if "normalization of FDG uptake for the body surface area" (SUVbsa) is independent of the patient's body size and is more reliable than SUVbw. METHODS: FDG-PET images were acquired on 44 patients (body weight range: 45-115 kg) with cancer. SUVbw [(mCi/g of tissue)/(mCi injected/patient body weight in g)] and SUVbsa [(mCi/g of tissue)/(mCi injected/patient BSA in m2)] were determined for the liver. Since most observers are accustomed to using the SUVbw, the two values were compared by setting the mean SUVbsa equal to that of SUVbw. RESULTS: SUVbw and SUVbsa were 3.42 +/- 0.85 (mean +/- s.d.) and 3.42 +/- 0.60, respectively. The standard deviation of the SUVbsa was smaller than that of SUVbw. More importantly, there was a strong positive correlation between SUVbw and, not only body weight (r = 0.75) but also BSA (r = 0.68), whereas only a weak correlation between SUVbsa and body weight (r = 0.41) or BSA (r = 0.38) was found with a near flat regression line. CONCLUSION: SUVbw overestimates FDG uptake in large patients. SUVbsa appears preferable to SUVbw, since it is minimally affected by the body size.

Assessing coronary artery disease with dipyridamole technetium-99m-tetrofosmin SPECT: a multicenter trial.

UNLABELLED: Exercise 99mTc-tetrofosmin myocardial scintigraphy is as accurate as exercise 201TI imaging. Thus far, no data are available on tetrofosmin imaging during pharmacologic stress. We evaluated the feasibility of using. 99mTc-tetrofosmin myocardial SPECT during vasodilation with dipyridamole for detecting coronary artery disease. METHODS: Sixty-four patients, enrolled in three centers in the U.S., underwent one-day dipyridamole/rest tetrofosmin SPECT. Coronary angiography, performed in 59 patients within 2 mo of the SPECT study, revealed normal coronary arteries or insignificant coronary stenosis in 11 patients and significant (> or = 50% luminal diameter stenosis) coronary stenoses in 48 patients. RESULTS: Sensitivity and specificity of tetrofosmin SPECT for detecting coronary artery disease were 85% and 55%, respectively, in the overall population and 81% and 55% in patients without prior coronary artery bypass surgery. The overall sensitivity and specificity of tetrofosmin tomographic imaging for detection of individual coronary stenoses were 53% and 72%, respectively, in the overall population and 54% and 80% in the patients without prior coronary artery bypass surgery. CONCLUSION: One-day dipyridamole/rest 99mTc-tetrofosmin myocardial perfusion imaging is feasible and has a high sensitivity for detection of coronary artery disease.

Radionuclide imaging in osteomyelitis.

The utility of bone imaging has remained significantly high despite the proven suboptimal specificity of the conventional three-phase bone scan. The quantitative four-phase study may play a role in maintaining its usefulness in the future. However, due to its extremely high sensitivity and excellent anatomical information, it remains as the first diagnostic study in most suspected cases of acute osteomyelitis. The future would see development of new imaging modalities aimed at enhancing the specificity for diagnosis of active osteomyelitis. The indium leucocyte study has been the single most important development in this respect in the last decade. NMR has been another important addition to complement the anatomical information for defining the extent and nature of infectious process--acute or chronic. It remains to be seen if the other investigative work on antigranulocyte antibodies or other imaging agents or techniques would make the future diagnosis of osteomyelitis more reliable and accurate using the nuclear medicine techniques.

Considerations in setting up a positron emission tomography center.

Clinically oriented imaging with position emission tomography (PET) has come of age. Given an adequate referral base and physician interest, a compelling argument can be made at all levels of the review process for setting up a PET program in a clinical setting. PET is expensive. It is obvious that the cost of running a PET service depends heavily on an institution's ability to obtain reasonable financing. Educational institutions have the opportunity to acquire special funding through a variety of sources. On the other hand, money can be expensive for private entrepreneurs. It appears that in the near future PET centers will probably remain at educational institutions or large well-financed community hospitals able to raise money at reasonable rates until reimbursement issues are better resolved. Finally, the future of clinical PET may hinge significantly on the ability of commercial radiopharmaceutical suppliers to provide regional fluorodeoxyglucose distribution. As an institutional program development, PET offers opportunities by providing unique clinical data aiding the referral pattern. PET may serve as a magnet for recruitment in many areas and may promote interdisciplinary cooperation. A clinical PET center serves both as a model for future and more widespread use of PET and as a training ground for medical personnel. Finally, the unique capabilities of PET may facilitate grant opportunities.

Comparative efficacy of positron emission tomography with fluorodeoxyglucose in evaluation of small (<1 cm), intermediate (1 to 3 cm), and large (>3 cm) lymph node lesions.

PURPOSE: Our objective was to determine if positron emission tomography (PET) with fluorodeoxyglucose (FDG; PET-FDG) imaging is equally efficacious in detection of metastases in small and large mediastinal lymph nodes as compared to CT scanning. MATERIALS AND METHODS: PET-FDG imaging, CT scanning, and histology results of sampled mediastinal lymph nodes were compared in 54 patients of total 118 patients studied. Efficacy of PET and CT was determined and compared in small (< 1 cm), intermediate (1 to 3 cm), and large (> 3 cm) mediastinal lesions. RESULTS: PET was accurate in 94% of patients in characterizing "N" disease as compared to 61% with CT. Overall, sensitivity, specificity, and accuracy of PET for staging mediastinal lymph nodes (n = 168 in 54 patients) was 96, 93, and 94%, as compared to 68, 65, and 66% with CT. Positive and negative predictive value of PET in detecting mediastinal adenopathy was 86% and 98%, as compared to 47% and 82% with CT, respectively. PET was also highly reliable and accurate for detecting lymph nodes < 1 cm, 1 to 3 cm, and > 3 cm in size with superior efficacy than CT. Sensitivity, specificity, and accuracy of PET for detecting malignancy in lymph node lesions < 1 cm in size was 97, 82, and 95%, respectively. CONCLUSION: PET-FDG imaging is equally reliable and accurate for detecting disease in small and large lymph node lesions in patients with suspected or proven lung cancer with better efficacy than CT.

Positron emission tomographic imaging with fluorodeoxyglucose isefficacious in evaluating malignant pulmonary disease.

OBJECTIVE: Positron emission tomography (PET), when used with the intravenously administered radiopharmaceutical F-18 fluorodeoxyglucose (FDG), has the potential to help in the evaluation of patients with lung cancer because the radiopharmaceutical is concentrated by metabolically active cells. We conducted a retrospective study of PET-FDG in 96 patients evaluated at our institution over the past 2 years for suspected primary pulmonary neoplasms. PET-FDG results were compared with the findings of computed tomographic scans on the same patients. All patients underwent surgical exploration with or without resection of the malignant tumors. Sites of potential malignancy were subjected to biopsy and/or excision, with subsequent pathologic evaluation. RESULTS: A total of 96 patients with suspected or proven primary pulmonary malignant disease were evaluated. Sixty-six patients had histologically confirmed malignant tumors, and 30 had benign masses histologically. PET-FDG had an accuracy of detecting malignancy in pulmonary lesions of 92% (sensitivity 97%; specificity 89%). A total of 111 surgically sampled sites were from lymph nodes. PET-FDG was accurate in predicting the malignancy of nodes in 91% of instances, whereas computed tomography was correct in 64%. The sensitivity, specificity, and predictive accuracy of PET in detecting metastatic lymphadenopathy in mediastinal lymph nodes were 98%, 94%, and 95%, respectively. PET-FDG also changed the M stage in 8 (12%) patients (6 with and 2 without metastases). The 6 malignant (positive) lesions were correctly identified by PET-FDG, and the 2 without tumor were accurately predicted as benign (negative). CONCLUSION: These initial results suggest that PET-FDG is highly accurate in identifying and staging lung cancer. PET-FDG also appears to be more accurate in detecting metastatic mediastinal lymphadenopathy than computed tomographic scan.