[Clinical and endoscopic characteristics of adult celiac disease].

Objective: The study aimed to analyze the clinical and endoscopic characteristics of adult celiac disease (CD) to provide a scientific basis for more effective CD diagnosis and treatment. Methods: In this cross-sectional study, the clinical and endoscopic data of 96 adult CD patients treated in the Department of Gastroenterology of the People's Hospital of Xinjiang Uygur Autonomous Region from March 2016 to December 2021 were retrospectively collected and analyzed. Results: A total of 96 CD patients were diagnosed, including 33 men and 63 women. The average age was 47±14 years (range, 18-81 years). The disease occurred mainly in the age group of 31-60 years. The median course of the disease was 2.0 (0.2-40.0) years. There were 41 (42.7%) classical and 55 (57.3%) non-classical CD patients. All patients with classical CD showed chronic diarrhea, often accompanied by abdominal pain (46.3%, 19/41), abdominal distension (17.1%, 7/41), anemia (65.9%, 27/41), and chronic fatigue (48.8%, 20/41). The main manifestations of non-classical CD were chronic abdominal pain (58.2%, 32/55), abdominal distension (32.7%, 18/55), anemia (40.0%, 22/55), and osteopenia/osteoporosis (38.2%, 21/55). Compared with non-classical CD, anemia developed more frequently in classical CD, and the difference was statistically significant (P = 0.012). The incidence of complications in CD patients was 36.5% (35/96), and the main complications were thyroid disease (19.8%, 19/96), connective tissue disease (6.2%, 6/96), and kidney disease (6.2%, 6/96). There was no significant difference between classical and non-classical CD (P>0.05). The frequency of endoscopic manifestations in CD patients was 84.4% (81/96). Duodenal bulb endoscopy showed nodular changes (72.9%, 70/96), grooved changes (10.4%, 10/96), and focal villous atrophy (9.4%, 9/96). The main manifestations of descending endoscopy were the decrease, flattening, or disappearance of duodenal folds (43.8%, 42/96), scallop-like changes (38.5%, 37/96), and nodular changes (34.4%, 33/96). Conclusions: Adult CD patients are mostly female. CD occurred mainly in the age group of 31-60 years. The clinical manifestations were mainly those of non-classical CD. Some patients often had other autoimmune diseases. Patients with characteristic endoscopic manifestations should be warned about the possibility of developing CD. Clinicians should strengthen the understanding of CD and reduce the related rates of missed diagnosis.

Polar meron lattice in strained oxide ferroelectrics.

A topological meron features a non-coplanar structure, whose order parameters in the core region are perpendicular to those near the perimeter. A meron is half of a skyrmion, and both have potential applications for information carrying and storage. Although merons and skyrmions in ferromagnetic materials can be readily obtained via inter-spin interactions, their behaviour and even existence in ferroelectric materials are still elusive. Here we observe using electron microscopy not only the atomic morphology of merons with a topological charge of 1/2, but also a periodic meron lattice in ultrathin PbTiO3 films under tensile epitaxial strain on a SmScO3 substrate. Phase-field simulations rationalize the formation of merons for which an epitaxial strain, as a single alterable parameter, plays a critical role in the coupling of lattice and charge. This study suggests that by engineering strain at the nanoscale it should be possible to fabricate topological polar textures, which in turn could facilitate the development of nanoscale ferroelectric devices.

[Operative effect and treatment strategies for the low distal humerus fracture].

Objective: To explore the operative effect and treatment strategies for the low distal humerus fracture. Methods: A retrospective analysis was conducted on the clinical data of 16 patients with the low distal humerus fracture between January 2016 and January 2018 at Department of Orthopaedics, Shanghai Tongji Hospital Affiliated to Tongji University.All fractures were coronal fractures of humeral head, partly combined fractures of humeral trochlea or posterior part. Fractures were classified according to Dubberley classification as 9 cases in type Ⅰ, 3 cases in typeⅡ and 4 cases in type Ⅲ.Selection of the kind of operative approach and internal fixation was made according to the fracture type and shape. For simple coronal fractures of humeral head or combining humeral trochlea fractures, which were relatively stable, single or multiple countersunk screws fixation by the lateral approach were chosen.For humeral head coronal fractures, which combining obviously displaced comminuted humeral trochlea factures, posterolateral locking plates and countersunk screws internal fixation by the olecranon osteotomy approach were chosen. The incision and elbow soft tissues were observed within 2 weeks after operation.The radiographic evaluation of fracture reduction, bone healing, internal fixation, arthritis and elbow range of motion were made at 3, 6, 12 months after operation. The Mayo elbow functional scores were documented for analysis of elbow joint function, and compared between different surgery groups by Kruskal-Wallis H test. Results: The follow-up time was (22.1±9.2)months(range: 15 to 39 months). The incisions healed well in 2 weeks after operation without soft tissue infection, necrosis or vascular complications. There was no fracture reduction loss or internal fixation loosening according to radiographic evaluation 3 months after operation. One case of ectopic ossification was observed 6 months after operation and inhibited by the treatment of non steroidal anti-inflammatory drugs.One case of ulnar neuritis occurred after operation and released after removing the long screw and loosing the ulnar.Osteoarthritis images were observed at the end of follow-up.Arc of motion was (120.4±11.2) ° in flexion and (5.5±1.9) ° in extension. The Mayo score was 88.7±9.1, including 11 excellent, 4 good, and 1 fair.The Mayo score was 90.1±3.7 in Dubberley classification type Ⅰcases, 89.7±4.6 in type Ⅱ cases and 84.5±5.8 in type Ⅲ cases. There were no significant differences in Mayo scores between 3 types cases according to Kruskal-Wallis H test. Conclusion: Choosing the appropriate surgical approach and composite internal fixation according to the fracture types and shapes of low distal humerus fracture, anatomic reduction of the articular surface and early functional exercise are the keys to obtain ideal curative effect.

[Effect of preoperative Nutritional Risk Screening-2002 combined with hematologic inflammatory markers on prognosis of thoracic esophageal squamous cell carcinoma].

Objective: To evaluate preoperative nutritional status and inflammatory status by Nutritional Risk Screening-2002 (NRS-2002) and hematologic inflammatory markers in patients with thoracic esophageal squamous cell carcinoma (ESCC), and to explore their effects on long-term survival prognosis. Methods: A total of 113 patients with thoracic ESCC treated by radical resection were grouped for further analysis according to preoperative NRS-2002 score, systemic inflammation score (SIS) and the combination of neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio (CNP) score. The progression free survival (PFS) and overall survival (OS) between groups were compared. Multivariate Cox regression analysis was used to determine the independent prognostic factors of patients with thoracic esophageal squamous cell carcinoma, and the interaction analysis of statistically significant factors was carried out. Results: The median PFS was 21 months for all the patients. The 1-year, 3-year and 5-year PFS rates were 69.0%, 25.7% and 23.1%, respectively. Correspondingly, the median OS was 36 months, and the 1-year, 3-year and 5-year OS rates were 95.6%, 46.2% and 29.2%, respectively. Cox univariate analysis showed that T stage, N stage, TNM stage, SIS, CNP score and NRS-2002 score were significantly associated with PFS and OS (all P<0.05), and sex was associated with PFS (P=0.032) in patients with thoracic ESCC. Furthermore, cox multivariate analysis showed that TNM stage (HR=1.570, P=0.039), NRS-2002 score (HR=2.706, P<0.001) and CNP score (HR=1.463, P=0.011) were independent prognosis factors of PFS in patients with thoracic ESCC. In cox model interaction analysis, there was a positive interaction between NRS-2002 score and CNP score (RR=2.789, P<0.001). Conclusion: Preoperative NRS-2002 score combined with CNP score are risk factors for prognosis of patients with thoracic ESCC, which can be used as prognostic indicators.

Modulating cAMP responsive element binding protein 1 attenuates functional and behavioural deficits in rat model of neuropathic pain.

OBJECTIVE: Chronic neuropathic pain (NP) has become a worldwide public health problem. This study was aimed to establish graded NP model to investigate the effect of CREB1 on nerve repair and NP after peripheral nerve injury. MATERIALS AND METHODS: Based on NP model, we measured the 50% paw withdrawal threshold (PWT) of rat hind paws and sciatic functional index (SFI). Luxol fast blue staining was performed to measure the ratio of distal myelin sheath to proximal (DPR). The c-Fos, GFAP, CX3CR1 and IBA-1 expressions in spinal cord were measured by Western blot. The expression levels of CREB1 and ATF-3 in dorsal root ganglion (DRG) were both measured. Intrathecal injection was performed by using recombinant CREB, or anti-CREB antibody for NP model, respectively. The above indexes were detected. RESULTS: In NP model, the 50% PWTs and DPR were gradually reduced and SFI was increased. The c-Fos, GFAP, CX3CR1 and IBA-1 expressions were increased compared to control group. The CREB1 and ATF-3 expressions in DRG showed gradually increase. With the injection of recombinant CREB, the similar changes were found in rats compared with NP model. While after anti-CREB1 antibody injection, all effects of CREB1 were impaired. Likewise, anti-CREB1 antibody treatment increased 50% PWT and DPR, decreased SFI, decreased expressions of c-Fos, GFAP, CX3CR1 and IBA-1. Besides, ATF-3 expression was inhibited by CREB1 suppression. CONCLUSIONS: CREB1 involved in the regulation of NP and nerve repair process, suggesting that CREB1 has potential as a new target for the treatment of chronic NP.

Unmasking chloride attack on the passive film of metals.

Nanometer-thick passive films on metals usually impart remarkable resistance to general corrosion but are susceptible to localized attack in certain aggressive media, leading to material failure with pronounced adverse economic and safety consequences. Over the past decades, several classic theories have been proposed and accepted, based on hypotheses and theoretical models, and oftentimes, not sufficiently nor directly corroborated by experimental evidence. Here we show experimental results on the structure of the passive film formed on a FeCr15Ni15 single crystal in chloride-free and chloride-containing media. We use aberration-corrected transmission electron microscopy to directly capture the chloride ion accumulation at the metal/film interface, lattice expansion on the metal side, undulations at the interface, and structural inhomogeneity on the film side, most of which had previously been rejected by existing models. This work unmasks, at the atomic scale, the mechanism of chloride-induced passivity breakdown that is known to occur in various metallic materials.

[Prognostic influence of preoperative Nutritional Risk Screening -2002 (NRS-2002) score for patients with thoracic esophageal squamous cell carcinoma receiving surgery].

Objective: To apply Nutritional Risk Screening-2002(NRS-2002) to perform nutritional status score for the patients with thoracic esophageal squamous cell carcinoma (ESCC) receiving surgery, and to explore the prognostic impact of long-term survival. Methods: A total of 117 patients who were diagnosed with ESCC from 2010 to 2012 were retrospectively analyzed. They recieved standard curative esophagectomy in the Yangzhou University Affiliated Taixing People's Hospital. The nutritional status and risk score for recruited patients were assessed according to the standard of NRS-2002 tool prior to surgery, and these patients were grouped for further analysis according to the median values of NRS-2002 score. Finally, the relationship between NRS-2002 score and prognosis was analyzed. Results: Patients were classified into two groups, with 45 in the NRS-2002<2.0 group, and 72 cases in the NRS-2002≥2.0, respectively. In the NRS-2002<2.0 group, the 1-, 3-, and 5-year progression-free survival (PFS) rates were 75.6%, 44.4% and 40.0% separately, while in the NRS-2002≥2.0 group, the PFS rates were 61.1%, 6.9% and 4.2% respectively, and the differences were statistically significant (P<0.001). Correspondingly, in the NRS-2002< 2.0 group, the 1-, 3-, and 5-year overall survival (OS) rates were 97.8%, 66.7% and 57.8% separately, while in the NRS-2002≥2.0 group, the OS rates were 91.7%, 33.3% and 16.7% respectively, and the differences were also statistically significant (P<0.001). Univariate analysis showed that N stage, TNM stage and NRS-2002 score were closely related to PFS and OS (P<0.05), and T stage was only associated with OS in patients with thoracic esophageal squamous cell carcinoma (P<0.05). Furthermore, multivariate Cox regression analysis showed that N stage (RR=1.640, 95% CI 1.049-2.565, P=0.030) and NRS-2002 (RR=3.154, 95% CI 1.946-5.113, P<0.001) were independent prognostic factors for PFS in patients with ESCC after surgery. Additionally, pathological differentiation (RR=1.556, 95% CI 1.004-2.440, P=0.041), N stage (RR=1.624, 95% CI 1.017-2.593, P=0.042) and NRS-2002 (RR=3.906, 95% CI2.245-6.795, P<0.001) were independent prognostic factors for OS in ESCC patients following surgery. Conclusion: Preoperative nutritional risk screening NRS-2002 score is an independent prognostic factor in patients with ESCC receiving surgery and could be used as a tool for primary screening for nutritional risk.

Tunable quad-band transmission response, based on single-layer metamaterials.

We investigated the electromagnetically induced transparency (EIT)-like effects in planar metamaterials (MMs) at microwave (GHz) frequencies. The specific MMs that were used in this study consist of cut-wire resonator/ring resonator, which achieved the dual EIT-like effects in a single-layer through the bright- and quasi-dark-mode coupling and the lattice mode coupling. In addition, by varying the distance between the two resonators, the quad-band EIT spectral response in the microwave region was obtained, and the group refractive index at the EIT-like resonance of proposed design reached up to 4,000. This study provides the design approach to the multispectral EIT-like effects and might suggest potential applications in a variety of fields, for example, low-loss slow-light device, multiple switching sensor, and other sensing devices.

An ultrahigh volumetric capacitance of squeezable three-dimensional bicontinuous nanoporous graphene.

Graphene with a large specific surface area and high conductivity has a large specific capacitance. However, its volumetric capacitance is usually very low because the restacking of 2D graphene sheets leads to the loss of the large ion-accessible surface area. Here we report squeezable bicontinuous nanoporous nitrogen-doped graphene, which is extremely flexible and can tolerate large volume contraction by mechanical compression without the face-to-face restacking occurring. The compressed nanoporous N-doped graphene with a large ion accessible surface area and high conductivity shows an ultrahigh volumetric capacitance of ∼300 F cm-3 together with excellent cycling stability and high rate performance.

Molecular genetic map construction and QTL analysis of fruit maturation period in grapevine.

In this study, we aimed at finding the genetic regularity of grape maturation period. Early-maturing grapevine, "87-1", was used as the female parent and late-maturing, "9-22", as the male parent, to create an F1 hybrid population. A total of 149 individual plants and their parents were selected as the mapping population. Sequence-related amplified polymorphism and simple-sequence repeat analyses were performed. We performed a linkage analysis and constructed a molecular genetic map. In the obtained map, the female and male parents each covered 19 linkage groups containing 188 and 175 maker loci, respectively. The total map distances for the female and male parents were 1074.5 and 1100.2 cM, respectively, whereas the average genetic distances between each two loci were 5.7 and 7.8 cM, respectively. The interval-mapping method was used in a quantitative trait locus (QTL) analysis for fruit maturation period. A total of 12 QTLs associated with fruit maturation period were detected. These included four QTLs in the male parent genetic map that were located in linkage groups M5, M11, M14-1, and M16, with a 62.6-75.7% rate of contribution of each QTL. Another three QTLs were found in the female parent genetic map, located in linkage groups F6, F14-1, and F18, with a 72.7-77.7% rate of contribution of each QTL. Five more QTLs were detected in the consensus map, located in linkage groups LG11, LG14-1, LG16, LG17, and LG18, with 8.9-75.7% phenotypic variance explained by each QTL.

Quantitative trait locus analysis of grape weight and soluble solid content.

A grapevine hybrid population was derived from a crossing of the early-maturing female parent cultivar '87-1' and the late-maturing male parent cultivar '9-22'. A total of 149 plants were selected from the hybrid population as the mapping population, and after sequence-related amplified polymorphism and simple-sequence repeat marker analysis were conducted we constructed molecular genetic maps of the parents. The molecular linkage map of '87-1' had 19 linkage groups that contained 188 markers, with an average interval of 5.7 cM and a total distance of 1074.5 cM; the '9-22' map had 19 linkage groups that contained 175 markers, with an average interval of 7.8 cM and a total distance of 1100.2 cM. The molecular linkage map of both parents had 19 linkage groups that contained 251 markers, with an average interval of 5.0 cM and a total distance of 1264.2 cM. We used the interval mapping method to conduct a quantitative trait locus (QTL) analysis of grape weight and soluble solid content of the mapping population. Six QTLs were related to grape weight, and the average contribution to the phenotypic variance was between 11.3 and 33.0%. Seven QTLs were related to soluble solid content, and the average contribution to the phenotypic variance was between 15.7 and 55.8%.

Species identification and evolutionary inference of the genera Megalobrama and Parabramis (Cyprinidae: Cultrinae) in China.

The species boundaries and evolutionary relationships of two closely related genera, Megalobrama and Parabramis, were inferred from the partial mitochondrial cytochrome oxidase subunit I (COI) gene, NADH dehydrogenase subunit 2 (ND2) gene and their concatenated segment. Phylogenetic reconstructions showed that among the three breams, Megalobrama amblycephala and Megalobrama skolkovii are more closely related to each other than either is to Megalobrama terminalis. The taxonomy of M. pellegrini should be reconsidered. The divergence time estimation based on the assumption of a global molecular clock indicated that speciation and dispersal of the two genera might have occurred at approximately Pliocene to Late Pleistocene, due to major paleo-environmental events associated with monsoon evolution and the formation of the Three Gorges of the Yangtze River.

Protein reactions with surface-bound molecular targets detected by oblique-incidence reflectivity difference microscopes.

We applied oblique-incidence reflectivity difference microscopes (a form of polarization-modulated nulling ellipsometry) to detection of biomolecular microarrays without external labeling in a study of protein reactions with surface-immobilized targets. We show that the optical reflectivity difference signals can be quantitatively related to changes in surface mass density of molecular layers as a result of the reactions. Our experimental results demonstrate the feasibility of using oblique-incidence reflectivity difference microscopes for high-throughput proteomics research such as screening unlabeled protein probes against libraries of surface-immobilized small molecules.

Population Structure, Chemotype Diversity, and Potential Chemotype Shifting of Fusarium graminearum in Wheat Fields of Manitoba.

This study was to investigate the variation of acetyl ester derivative of DON at 15-position oxygen (15ADON) and acetyl ester derivative of DON at 3-position oxygen (3ADON) chemotypes and potential chemotype shifting of Fusarium graminearum based on the population structure of this species in Manitoba. The study was conducted in 15 locations with wheat cvs. Superb and AC Barrie in Manitoba from 2004 to 2005. Percentages of chemotypes 3ADON and 15ADON of F. graminearum ranged from 0 to 95.7 and 4.3 to 100%, respectively. The 3ADON chemotype was distributed in the southern part of Manitoba and predominant in Morris and Horndean. The two chemotypes almost shared the same percentage in Portage la Prairie. The 15ADON chemotype was predominant in the other locations. Significant gene flow was found among the populations from Sanford, Portage la Prairie, Hamiota, Plumas, Rapid City, and Virden; the populations from Cartier, Rivers, Killarney, and Souris; and the populations from Morris, Kenville, and Dauphin. There were no differences between the populations from two wheat cultivars and two chemotypes. The great variation of chemotype likely resulted from the great genetic diversity of F. graminearum. Sexual recombination, population age, and cropping system could result in genetic and chemotypic diversities. Wheat seed shipment and long-distance spore transportation of F. graminearum potentially caused the genetic migration and chemotype shifting in Manitoba.

Genetic Diversity of Gibberella zeae Isolates from Manitoba.

Gibberella zeae (anamorph Fusarium graminearum) causes Fusarium head blight, one of the most important diseases of cereals in the Canadian prairies for the last decade. In 2002, 60 isolates of G. zeae were collected and single spored from naturally infected spikes of wheat from Carman and Winnipeg in Manitoba. These isolates were compared using vegetative compatibility analysis and polymerase chain reaction (PCR)-based sequence related amplified polymorphisms (SRAP). Sixteen vegetative compatibility groups (VCG) were found among the 50 isolates tested. Five VCGs were found in the two locations, five in Carman and six in Winnipeg. Eight SRAP primer pairs amplified 90 polymorphic DNA fragments from 60 isolates and identified 59 distinct haplotypes. Among seven pairs of isolates, each pair from a distinct spike, four had isolates with different VCGs and six comprised different SRAP haplotypes. Principal component analysis and UPGMA separated the dataset into two main groups, each with isolates from both locations. The analysis of molecular variance also revealed that 75 and 20% of the variance was associated with differences among individual isolates and varieties sampled, respectively. Geographic location was not a significant source of variation at P = 0.05 and accounted for only 4% of total variance. A low correlation between VCG and SRAP marker data was detected. This study showed that, although genetic diversity is high among G. zeae isolates, Carman and Winnipeg collections have a similar genetic makeup and are likely part of the same population. The significant proportion of variance accounted by the variety compared with the geographic origin of isolates suggests that seedborne inoculum might have contributed to the genetic diversity within the G. zeae collection under study.

Seasonal and Diurnal Patterns of Spore Dispersal by Leptosphaeria maculans from Canola Stubble in Relation to Environmental Conditions.

Seasonal and diurnal patterns of spore dispersal by Leptosphaeria maculans, which causes blackleg disease of canola, were studied in two consecutive field seasons using a 7-day Burkard spore sampler and rotorod impaction spore samplers. Ascospores of L. maculans were trapped from mid-June to the end of July, whereas pycnidiospores were trapped from mid-July until the end of July or early August. Ascospores and pycnidiospores were trapped between 9:00 P.M. and 4:00 A.M., when air temperatures were 13 to 18°C and relative humidity was >80%. Peak ascospore and pycnidiospore dispersal was associated with rain events. Peak ascospore dispersal was found to occur several hours after rainfall ≥2 mm, and ascospore dispersal continued for approximately 3 days after such events. Peak pycnidiospore dispersal occurred during the same hours as rain events. More ascospores and pycnidiospores were carried in the direction of prevailing winds than in other directions. To the south of the inoculated area, the gradients of disease incidence and stem disease severity were -19.2 and -0.8 m-1, respectively. Disease incidence and stem severity declined by 50% 12.5 and 5.5 m from the inoculated area, respectively. To the north of the inoculated area, the gradients of disease incidence and stem severity were -21.5 and -0.7 m-1, respectively. Disease incidence and stem severity declined by 50% 14.0 and 5.2 m from the inoculated area, respectively. In 2001, ascospores and pycnidiospores were trapped within 25 m of the inoculated area, whereas pycnidiospores were trapped up to 45 m from the inoculated area.

[Direct determination of selenium and bismuth in antimony and antimony compound by hydride generation-atomic fluorescence spectrometry].

The interference of Sb in determination of Se and Bi in antimony powder and antimony compound has been studied in different acidity, it is found that the interference of antimony has been reduced apparently in high acidity. Simultaneously, according to the difference of hydride generation reaction between Sb5+ and Sb3+, a sensitive and rapid method has been developed and used to determine Se and Bi in real samples. The recovery of the method is 95%-105% for practical samples. Detection limits are 0.00004 x 10(-2) (content) for Se and 0.0001 x 10(-2) mg.L-1 (content) for Bi respectively. The relative standard deviations of Se are 2.4% (content = 0.00169 x 10(-2) mg.L-1) and 5.4% (content = 0.00056 x 10(-2) mg.L-1). The relative standard deviations of Bi are 5.0% (content = 0.00024 x 10(-2) mg.L-1) and 1.3% (content = 0.00229 x 10(-2) mg.L-1). The method has been applied to determination of Se and Bi in practical samples with satisfactory results.

The common nodulation genes of Astragalus sinicus rhizobia are conserved despite chromosomal diversity.

The nodulation genes of Mesorhizobium sp. (Astragalus sinicus) strain 7653R were cloned by functional complementation of Sinorhizobium meliloti nod mutants. The common nod genes, nodD, nodA, and nodBC, were identified by heterologous hybridization and sequence analysis. The nodA gene was found to be separated from nodBC by approximately 22 kb and was divergently transcribed. The 2. 0-kb nodDBC region was amplified by PCR from 24 rhizobial strains nodulating A. sinicus, which represented different chromosomal genotypes and geographic origins. No polymorphism was found in the size of PCR products, suggesting that the separation of nodA from nodBC is a common feature of A. sinicus rhizobia. Sequence analysis of the PCR-amplified nodA gene indicated that seven strains representing different 16S and 23S ribosomal DNA genotypes had identical nodA sequences. These data indicate that, whereas microsymbionts of A. sinicus exhibit chromosomal diversity, their nodulation genes are conserved, supporting the hypothesis of horizontal transfer of nod genes among diverse recipient bacteria.

Modulation of CPP32 activity and induction of apoptosis in Human CEM X 174 lymphocytes by heptachlor, a chlorinated hydrocarbon insecticide.

Heptachlor is an organochlorine insecticide used worldwide for the control of pests both agriculturally and domestically. Its lipophilic structure allows it to bioaccumulate and pass through the food chain, exposing those who come in contact with it to its tumor promoting and possible carcinogenic effects. As a mechanism of tumor promotion, we explored the possibility of heptachlor suppressing the apoptotic process in human CEM x 174 lymphocytes. In this article, we describe the effect of heptachlor on the activity of the apoptosis protease CPP32. We show that heptachlor by itself was able to stimulate CPP32 activity at relatively high concentrations. When combined with the chemotherapeutic agent doxorubicin, a known CPP32 activator, a dual effect was observed. Low concentrations of heptachlor (5 microM-10 microM) suppressed doxorubicin-induced CPP32 activity, and high concentrations of heptachlor (80 microM-120 microM) augmented it. We also showed that heptachlor alone at relatively high concentrations induced apoptosis-associated changes in CEM x 174 cells including high molecular weight (HMW) DNA cleavage and chromatin condensation. From these results, it appears that heptachlor has tumor promoting-like effects at lower concentrations, and at higher concentrations induces apoptosis as a mechanism of cytotoxicity.

The effect of diet on plasma homocysteine concentrations in healthy male subjects.

OBJECTIVE: To determine the effect of habitual omnivorous and vegetarian diets on folate and vitamin B12 status and the subsequent effect on homocysteine concentration. DESIGN: Cross-sectional comparison of free-living habitual meat-eaters and habitual vegetarians. SETTING: The study was conducted at RMIT University, Melbourne. SUBJECTS: One hundred and thirty-nine healthy male subjects (vegans n=18, ovolacto vegetarians n=43, moderate meat-eaters n=60 and high meat-eaters n=18) aged 20-55 y who were recruited in Melbourne. OUTCOME MEASURES: Fasting plasma or serum from each subject was analysed for folate, vitamin B12 and homocysteine concentration. A semi-quantitative Food Frequency Questionnaire was completed by a subset of subjects from each group to determine methionine intake. RESULTS: The two meat eating groups consumed significantly greater levels of methionine (P<0.001). There was no clear trend in plasma folate status between groups, however the plasma vitamin B12 concentration decreased progressively from the high-meat-eating group to vegans (P<0.05). An inverse trend was observed with plasma homocysteine concentration, with vegans showing the highest levels and high meat eaters the lowest (P<0.05). CONCLUSIONS: Dietary methionine intake has no observable effect on plasma homocysteine concentration. In habitual diets, where folate intake is adequate, lowered vitamin B12 intake from animal foods leads to depleted plasma vitamin B12 concentration with a concomitant increase in homocysteine concentration. The suggested mechanism is the failure to transfer a methyl group from methyl tetrahydrofolate by vitamin B12 in the remethylation of homocysteine to methionine.