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Phytoremediation is a promising area of new research, both for its low cost and great benefit to society in the clean retrieval of contaminated sites. Phytoremediation is the use of living green plants for in situ risk reduction and/or removal of contaminants from contaminated soil, water, sediments, and air. Specially selected or engineered plants are used in the process. The soil samples were taken from Cuddalore Old Town (OT) and the samples from SIPCOT industrial complex, which was the study area and analyzed for various metals concentrations. Fifteen metals have been analyzed by adopting standard procedure. The detection limits of metal concentration are drawn as control. The various (15) metal concentrations in the soil samples were found higher in soil taken from SIPCOT industrial complex, compared with samples taken from Cuddalore OT. In all the observations, it was found that most of the metals like calcium, cadmium, chromium, cobalt, nickel, and zinc showed maximum concentrations, whereas arsenic, antimony, lead, magnesium, sodium have shown minimum concentrations, both when compared with control. From the present study, it was found that the soil collected from SIPCOT complex area were more polluted due to the presence of various industrial effluents, municipal wastes, and sewages when compared with the soil collected from Cuddalore OT.  相似文献   
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Species-specific differences encountered in the nucleotide sequences of a highly variable region of the 18S rRNA gene were used to design a multiplex polymerase chain reaction (PCR) assay for the identification of Phlebotomus papatasi Scopoli and Phlebotomus argentipes An-nandale & Brunetti, vectors of Leishmania. This multiplex PCR assay uses a common forward primer and two reverse primers, which are specific for the two species. Amplification of a PCR product of size 788 bp indicates the presence of P. papatasi, whereas a product of size 677 bp indicates the presence of P. argentipes. The assay was found to be highly specific and sensitive.  相似文献   
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OBJECTIVE

Paraoxonase (PON) exhibits esterase activity (PON-AREase) and lactonase activity (PON-HCTLase), which prevent LDL oxidation and detoxify homocysteine thiolactone (HCTL). The role of HCTL and PON-HCTLase as a risk factor for the microvascular complication in diabetic retinopathy at the level of vitreous has not been investigated.

RESEARCH DESIGN AND METHODS

Undiluted vitreous from patients with proliferative diabetic retinopathy (PDR) (n = 13) and macular hole (MH) (n = 8) was used to determine PON-HCTLase and PON-AREase activity spectrophotometrically. HCTL levels were detected by liquid chromatography–tandem mass spectrometry. In vitro studies were done in primary cultures of bovine retinal capillary endothelial cells (BRECs) to determine the dose- and time-dependent effect of HCTL and homocysteine (Hcys) on PON-HCTLase activity, as well as to determine mRNA expression of PON by RT-PCR.

RESULTS

A significant increase in HCTL and PON-HCTLase activity was observed in PDR compared with MH (P = 0.036, P = 0.001), with a significant positive correlation between them (r = 0.77, P = 0.03). The in vitro studies on BRECs showed a dose- and time-dependent increase in the PON-HCTLase activity and mRNA expression of PON2 when exposed to HCTL and Hcys.

CONCLUSIONS

This is the first study showing elevated levels of vitreous HCTL and PON-HCTLase activity in PDR. These elevations are probably a protective effect to eliminate HCTL, which mediates endothelial cell dysfunction. Thus, vitreous levels of HCTL and PON activity can be markers of diabetic retinopathy. The bioinformatics analysis reveals that the structure and function of PON that can be modulated by hyperhomocysteinemia in PDR can affect the dual-enzyme activity of PON.Hyperhomocysteinemia is a well-established independent risk factor for the development of macrovascular and microvascular diseases (1). Recent reports show that increased homocysteine thiolactone (HCTL) levels are associated with diabetic macrovasculopathy (2). HCTL is formed in all cell types as a result of error-editing met-tRNA synthetase when there is excess homocysteine (Hcys). The interaction of HCTL with proteins leads to protein homocysteinylation and loss of function (3). Therefore, detoxification of HCTL is crucial. This is possible by the lactonase (HCTLase) activity of paraoxonase (PON) (4). The enzyme PON is a calcium-dependent 45-kDa protein coded by chromosome 7q21-22. The PON gene family in humans has three members: PON1, PON2, and PON3. Whereas PON1 and PON3 are associated with serum HDL (5), PON2 is ubiquitously expressed in tissues (6). PON1 exhibits antioxidant properties, thereby preventing the accumulation of oxidized LDL, and PON2 acts mainly at the cellular level (7). Lipid oxidation plays a role not only in macrovascular diseases but also in microvascular dysfunction, and serum PON1 activity was decreased in patients with diabetic retinopathy (8). While elevated Hcys in the vitreous of patients with proliferative diabetic retinopathy (PDR) was reported by us and others (9,10), there are no reports on HCTL levels and PON activity. This study aims to detect the vitreous levels of HCTL, PON-HCTLase, and esterase (PON-AREase) activity in PDR case subjects and in in vitro studies in bovine retinal capillary endothelial cells (BRECs).  相似文献   
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Background

Benign anastomotic strictures occur frequently after esophagectomy, and impact on postoperative recovery, nutritional status, and quality of life. This large cohort study explored the incidence of stricture after transthoracic (2- and 3-stage) and transhiatal resections with uniform single-layer sutured anastomotic technique, and aimed to identify independent risk factors.

Methods

Patients undergoing esophagectomy with gastric conduit reconstruction between February 2001 and October 2014 were studied prospectively. Symptomatic anastomotic stricture was defined as dysphagia requiring endoscopic dilatation, and refractory strictures as those requiring >5 dilatations. Multivariable logistic regression was performed to determine factors independently associated with stricture development.

Results

Five-hundred and twenty-four patients, 77 % with adenocarcinoma, underwent esophagectomy [2-stage, n = 328 (62.6 %); 3-stage, n = 129 (23.3 %); transhiatal, n = 74 (14.1 %)], with an overall inhospital mortality rate of 2.7 %. 58.5 % of patients received neoadjuvant therapy [chemotherapy only, n = 119 (22.7 %); chemoradiation, n = 188 (35.9 %)]. Anastomotic stricture developed in 125 patients (24.5 %), was refractory in 20 (3.9 %) and required a median of 2 dilatations (range 1–18). On multivariable analysis, ASA grade (P < 0.05), cervical anastomosis (P < 0.001), and a significant postoperative cardiac event (P < 0.05) were independently associated with stricture risk. Refractory strictures were independently associated with anastomotic leak (P = 0.01) and transhiatal resections (P < 0.001).

Conclusion

Benign anastomotic strictures are common, particularly with cervical reconstruction, and after transhiatal resection. Refractory strictures are rare. Where fitness and oncologic equivalence apply, a thoracic anastomosis provides significant advantages compared with a cervical anastomosis in terms of anastomotic stricture risk.
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Internal hernia is herniation of a viscus, usually in the small bowel, through a normal or abnormal aperture within the peritoneal cavity. Its incidence has been reported to be one to two per cent. Internal hernias are classified based on location, and the hernial orifice can be either congenital or acquired. Paraduodenal hernias are the most common type (53 per cent). Paraduodenal hernia is often a misnomer and is referred to as a mesocolic hernia. Left and right mesocolic hernias are common, while middle and transverse types are rare. We are reporting a rare congenital middle mesocolic hernia presenting as a complete transection of the small intestine due to blunt injury to the abdomen.  相似文献   
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