Assembly of the FKBP51-PHLPP2-AKT signaling complex in cerebral ischemia/reperfusion injury in rats

The imbalance of cell pro-death and pro-survival signaling pathways determines the neuronal fate during cerebral ischemia/reperfusion (I/R) injury. However, the biological mechanisms regulating the balance between activation of the pro-death or the pro-survival signaling pathways remain unclear. In this study, a rat model of I/R injury was established using four-vessel occlusion followed by different times of reperfusion. I/R injury did not affect the level of FK506 binding protein 51 (FKBP51), PH domain and leucine rich repeat protein phosphatases (PHLPP)-2, and AKT, but induced assembly of the FKBP51-PHLPP2-AKT signaling complex, as indicated by the enhancement of interactions among these compounds following reperfusion. Using an antisense oligonucleotide, PHLPP2 expression was effectively inhibited. Critically, the inhibition of PHLPP2 prohibited the interactions of FKBP51, PHLPP2 and AKT, reversed the decrease of p-AKT expression and increased the expression of p-JNKs and p-c-Jun elicited by I/R injury. In addition, PHLPP2 inhibition reversed I/R-injury-induced Caspase-3 cleavage and loss of pyramid neurons in the CA1 region of hippocampus. The results of the current study indicate that the assembly of the FKBP51-PHLPP2-AKT signaling complex plays a critical role in mediating cell death in I/R injury. The inhibition of PHLPP2 via antisense oligonucleotide treatment may be an effective method to prohibit the assembly of the FKBP51-PHLPP-AKT signaling complex, thus balancing the cell pro-survival and pro-death signaling pathways ultimately mitigating cell death in I/R injury.

Effect of a carbohydrate-containing late-evening snack on energy metabolism and fasting substrate utilization in adults with acute-on-chronic liver failure due to Hepatitis B

BACKGROUND/OBJECTIVES

This study investigates the effects of a carbohydrate (CHO; lotus-root starch) predominant, late-evening snack (LES), containing 200 kcal (50 g CHO) on fasting resting energy expenditure (REE) and nutrient oxidation in hospitalized adults with acute-on-chronic liver failure (ACLF).

SUBJECTS/METHODS

Adults with ACLF were randomized to receive daily LES (treatment; n=35) or standard care (n=35; non-supplemented control) for 14 days. REE and respiratory quotient (RQ) were measured by indirect calorimetry, nutrient oxidation (CHO, protein and fat), intake and biochemical parameters were measured in both groups at baseline and after 14 days using validated techniques. Disease severity was measured using the model for end-stage liver disease (MELD).

RESULTS

No significant differences in macronutrient intake, anthropometric, demographic characteristics or MELD scores were observed between groups at baseline (P>0.05). Fasting RQ was significantly higher in the LES supplemented verses the control group after 2 weeks (P=0.02). CHO oxidation was significantly higher (P=0.001) and fat oxidation (P=0.02) was lower in the LES-supplemented group when compared with controls after 2 weeks. Fasting RQ and REE in the LES-supplemented group increased significantly (0.83 verses 0.88; P=0.007/1301±409 vs 1687±718 kcal/day; P=0.02) in patients with MELD scores 30 when compared with patients with MELD scores >30 (0.82 verses 0.84; P=0.27/ 1361±405 vs 1437±429 kcal/day; P=0.67) after supplementation.

CONCLUSIONS

A carbohydrate-predominant LES is associated with increases in fasting carbohydrate oxidation, REE and reductions in fat oxidation in adults with ACLF. Therapeutic strategies utilizing LES may promote improved nutritional status in adults with ACLF.

Overexpression of the cytochrome P450 monooxygenase (cyp71av1) and cytochrome P450 reductase (cpr) genes increased artemisinin content in Artemisia annua (Asteraceae)

Finding an efficient and affordable treatment against malaria is still a challenge for medicine. Artemisinin is an effective anti-malarial drug isolated from Artemisia annua. However, the artemisinin content of A. annua is very low. We used transgenic technology to increase the artemisinin content of A. annua by overexpressing cytochrome P450 monooxygenase (cyp71av1) and cytochrome P450 reductase (cpr) genes. CYP71AV1 is a key enzyme in the artemisinin biosynthesis pathway, while CPR is a redox partner for CYP71AV1. Eight independent transgenic A. annua plants were obtained through Agrobacterium tumefaciens-mediated transformation, which was confirmed by PCR and Southern blot analyses. The real-time qPCR results showed that the gene cyp71av1 was highly expressed at the transcriptional level in the transgenic A. annua plants. HPLC analysis showed that the artemisinin content was increased in a number of the transgenic plants, in which both cyp71av1 and cpr were overexpressed. In one of the transgenic A. annua plants, the artemisinin content was 38% higher than in the non-transgenic plants. We conclude that overexpressing key enzymes of the biosynthesis pathway is an effective means for increasing artemisinin content in plants.

[Effects of sodium aescinate on the apoptosis-related genes in lung injury induced by intestinal ischemia reperfusion in rats]

OBJECTIVE

To investigate the relationship between apoptosis-related genes and lung injury induced by intestinal ischemia reperfusion and to explore the effects and its possible mechanism of sodium aescinate.

METHODS

Rat model of intestinal I/R injury was established with clamping of the superior mesenteric artery for 60 min and then clamping was relieved for 60 min. Twenty-four SD rats were randomly divided into three groups with eight rats in each: sham group, intestinal ischemia/reperfusion group (I/R group) and sodium aescinate group (SA + I/R group). Lung wet/dry weight ratio, lung coefficient and Superoxide dismutase (SOD), malondialdehyde (MDA) in plasma and lung tissue were measured, as well as the expression levels of Bcl-2 and Bax proteins in lung tissue were examined using immunohistochemical method.

RESULTS

Compared with sham group, lung wet/dry weight ratio, lung coefficient and MDA in plasma and lung tissue were significantly increased, and while the activity of SOD in plasma and lung tissue were decreased significantly in I/R group. At the same time, the protein expression level of Bcl-2 and Bax were significantly increased. But Bax protein expression was much greater than that of Bcl-2, the ratio of Bcl-2 to Bax was decreased significantly in I/R group than that in sham group. Compared with I/R group, lung wet/dry weight ratio, lung coefficient and MDA in plasma and lung tissue were significantly decreased, and while the activity of SOD in serum and lung tissue were significantly increased in SA + I/R group. At the same time, Bax protein expression was significantly decreased, both Bcl-2 protein expression and the ratio of Bcl-2 to Bax were significantly increased in SA + I/R group than that in I/R group.

CONCLUSION

Lung injury induced by intestinal ischemia reperfusion is correlated with abnormal expression levels of Bcl-2 and Bax protein which is caused by oxidative injury. Sodium aescinate can protect the lung injury induced by intestinal ischemia/reperfusion (I/R), which may be mediated by inhibiting lipid peroxidation, upregulating Bcl-2 gene protein expression, improving the ratio of Bcl-2/ Bax to inhibit lung apoptosis.

EZH2 genetic variants affect risk of gastric cancer in the Chinese Han population

Enhancer of zeste 2 (EZH2) gene encodes a histone methyltransferase that constitutes the catalytic component of the polycomb repressive complex-2 (PRC2) to initiate epigenetic silencing of genes. It is reported that the expression level of EZH2 in gastric cancer tissue was highly correlated with tumor progression, however, whether EZH2 genetic variants were associated with the risk of gastric cancer remains yet unknown. In this study, we conducted a genotyping analysis for EZH2 in 311 cases of gastric cancer and 425 controls from the Chinese Han population. We found five single nucleotide polymorphisms (SNP; rs12670401, rs6464926, rs2072407, rs734005, and rs734004) of EZH2 gene were significantly associated with the risk of gastric cancer. Of which, the rs12670401 with the minor allele C and rs6464926 with the minor allele T revealed strong associations with increased gastric cancer risk [P = 0.009, adjusted odds ratio (aOR) = 1.327, 95% CI = 1.075-1.683 and P = 0.012, aOR = 1.310, 95% CI = 1.059-1.619]. The other three SNPs, rs2072407, rs734005, and rs734004 contributed to significantly reduced risk of gastric cancer (P = 0.033, aOR = 0.787, 95% CI = 0.633-0.981, P = 0.045, aOR = 0.799, 95% CI = 0.642-0.995 and P = 0.048, aOR = 0.803, 95% CI = 0.645-0.999), respectively. We further found that rs12670401 and rs6464926 were in a strong LD while rs2072407, rs734005, and rs734004 were in another. Haplotype analysis of the five SNPs showed that haplotype CCTCT reduced the risk of gastric cancer (P = 0.031 and aOR = 0.784), while haplotype GTCTC significantly elevated the risk of gastric cancer (P = 0.011 and aOR = 1.310). We concluded that EZH2 variants were significantly associated with gastric cancer risk. Our results for the first time provided new insight into susceptibility factors of EZH2 gene variants in carcinogenesis of gastric cancer of the Chinese Han population.

Psoriasis regression analysis of MHC loci identifies shared genetic variants with vitiligo

Psoriasis is a common inflammatory skin disease with genetic components of both immune system and the epidermis. PSOR1 locus (6q21) has been strongly associated with psoriasis; however, it is difficult to identify additional independent association due to strong linkage disequilibrium in the MHC region. We performed stepwise regression analyses of more than 3,000 SNPs in the MHC region genotyped using Human 610-Quad (Illumina) in 1,139 cases with psoriasis and 1,132 controls of Han Chinese population to search for additional independent association. With four regression models obtained, two SNPs rs9468925 in HLA-C/HLA-B and rs2858881 in HLA-DQA2 were repeatedly selected in all models, suggesting that multiple loci outside PSOR1 locus were associated with psoriasis. More importantly we find that rs9468925 in HLA-C/HLA-B is associated with both psoriasis and vitiligo, providing first important evidence that two major skin diseases share a common genetic locus in the MHC, and a basis for elucidating the molecular mechanism of skin disorders.

The effect of overweight and obesity on psoriasis patients in Chinese Han population: a hospital-based study

BACKGROUND

Accumulating evidence indicates that psoriasis is associated with increased risk of overweight and obesity. However, few studies have investigated this relationship in Chinese Han population.

OBJECTIVE

The aim of this study was to explore the relationship between overweight/obesity and psoriasis and to evaluate the overweight/obesity effect on the clinical features of psoriasis in Chinese Han population.

METHODS

A hospital-based study was conducted, which involved in 4452 patients and 1166 controls of Chinese Han through epidemiological investigation. Controls used in the study were individuals without psoriasis from health examination centre, and other skin disease patients from outpatient department.

RESULTS

Compared with the control group, a significantly greater prevalence of overweight and obesity was observed in psoriasis patients. The estimated ORs were 1.301 (95% CI, 1.105-1.531) and 1.680 (95% CI, 1.134-2.491) respectively. The disease severity of psoriasis measured by psoriasis area and severity index (PASI) was statistically correlated with body mass index (BMI) (r = 0.184, P < 0.01). Moreover, a high proportion of overweight patients had affected hands or/and feet, buttocks, trunk, legs, arms and arthritis (P < 0.01).

CONCLUSIONS

Our study suggested that psoriatic patients have a higher prevalence of overweight and obesity compared with non-psoriatic patients in Chinese Han population. Overweight and obesity has different risk effect on severity and manifestations of psoriasis and might be useful for better evaluating psoriasis clinically.

Overexpression of α-2,6 sialyltransferase stimulates propagation of human influenza viruses in Vero cells

Human influenza viruses are major concern as the leading cause of global pandemics. In infecting cells, they preferentially bind to sialyloligosaccharides containing terminal N-acetyl sialic acid linked to galactose by an α-2,6-linkage (NeuAcα2,6Gal). The amount of NeuAcα2,6Gal in Vero cells, which are predominantly used for production of influenza vaccines over the past 30 years, may not be as high as that in epithelial cells of human respiratory tract, what leads to the suboptimal virus growth in Vero cells. In this study, we stably transfected Vero cells with cDNA of human α-2,6-sialyltransferase (SIAT1), an enzyme catalyzing α-2,6-sialylation of galactose on glycoproteins. Overexpression of SIAT1 in the transfected Vero cells (Vero-SIAT1 cells) was confirmed by Western blot analysis and immunofluorescence microscopy. Vero-SIAT1 cells expressed 7 times higher amounts of NeuAcα2,6Gal, but 3 times lower amounts of NeuAcα2,3Gal as compared to parental Vero cells. Furthermore, the influenza viruses A (H1N1 and H3N2) and B grew in Vero-SIAT1 cells to the higher titers than in Vero cells. Taken together, these results imply that Vero-SIAT1 cells are useful not only for the propagation of human influenza viruses, but also for the preparation of influenza vaccines.

Variants in MHC, LCE and IL12B have epistatic effects on psoriasis risk in Chinese population

BACKGROUND

Psoriasis has long been considered as a complex disease, and gene-gene or gene-environment interactions may jointly influence the etiology for psoriasis.

OBJECTIVE

We evaluated the associations of single nucleotide polymorphisms (SNPs) in MHC region, and determined the epistasis and combined effects of MHC locus and IL12B, LCE on risk for psoriasis.

METHODS

We genotyped SNP rs1265181 (MHC) in 5067 cases and 6404 controls, combining with the prior GWAS data (1139 cases and 1132 controls), we explored the genetic interaction among MHC locus, LCE and IL12B by using logistic regression analysis. We evaluated the combined effects of MHC locus and two non-MHC loci in the combined sample of 6206 cases and 7536 controls.

RESULTS

Extremely high significance of association was detected between rs1265181 and psoriasis (p combined < 10E--300, OR = 16.52, 95% CI: 15.28-18.44). We observed significant interactions between MHC and LCE (p = 0.0016) and between MHC and IL12B (p = 0.0036). The risk increased some 26-fold in individuals with risk alleles in both MHC and LCE as compared with those without risk alleles, and individual carrying risk alleles of MHC and IL12B has around 36-fold higher risk of psoriasis than those with protective alleles.

CONCLUSIONS

This study provides evidence for the epistatic effects between MHC locus and LCE, IL12B genes. Besides, we suggest that MHC might be the main effect gene on the risk for psoriasis. This data may contribute to our understanding of psoriasis genetic interactions and account for the additional risk of certain patients to develop psoriasis.

Association analyses identify six new psoriasis susceptibility loci in the Chinese population

We extended our previous genome-wide association study for psoriasis with a multistage replication study including 8,312 individuals with psoriasis (cases) and 12,919 controls from China as well as 3,293 cases and 4,188 controls from Germany and the United States and 254 nuclear families from the United States. We identified six new susceptibility loci associated with psoriasis in the Chinese study containing the candidate genes ERAP1, PTTG1, CSMD1, GJB2, SERPINB8 and ZNF816A (combined P < 5 × 10⁻⁸) and replicated one locus, 5q33.1 (TNIP1-ANXA6), previously reported (combined P = 3.8 × 10⁻²¹) in the European studies. Two of these loci showed evidence for association in the German study at ZNF816A and GJB2 with P = 3.6 × 10⁻³ and P = 7.9 × 10⁻³, respectively. ERAP1 and ZNF816A were associated with type 1 (early onset) psoriasis in the Chinese Han population (test for heterogeneity P = 6.5 × 10⁻³ and P = 1.5 × 10⁻³, respectively). Comparisons with the results of previous GWAS of psoriasis highlight the heterogeneity of disease susceptibility between the Chinese and European populations. Our study identifies new genetic susceptibility factors and suggests new biological pathways in psoriasis.

Genome-wide association study in a Chinese Han population identifies nine new susceptibility loci for systemic lupus erythematosus

We performed a genome-wide association study (GWAS) of systemic lupus erythematosus (SLE) in a Chinese Han population by genotyping 1,047 cases and 1,205 controls using Illumina Human610-Quad BeadChips and replicating 78 SNPs in two additional cohorts (3,152 cases and 7,050 controls). We identified nine new susceptibility loci (ETS1, IKZF1, RASGRP3, SLC15A4, TNIP1, 7q11.23, 10q11.22, 11q23.3 and 16p11.2; 1.77 x 10(-25) < or = P(combined) < or = 2.77 x 10(-8)) and confirmed seven previously reported loci (BLK, IRF5, STAT4, TNFAIP3, TNFSF4, 6q21 and 22q11.21; 5.17 x 10(-42) < or = P(combined) < or = 5.18 x 10(-12)). Comparison with previous GWAS findings highlighted the genetic heterogeneity of SLE susceptibility between Chinese Han and European populations. This study not only advances our understanding of the genetic basis of SLE but also highlights the value of performing GWAS in diverse ancestral populations.

The analysis of genetics and associated autoimmune diseases in Chinese vitiligo patients

Vitiligo is a common skin and hair depigmentary disorder that results from selective destruction of melanocytes. It occurs in a typical multifactorial, polygenic inheritance. Several studies have indicated that vitiligo is associated with some autoimmune diseases. In this paper we examined 6,516 vitiligo patients including clinical characteristics, familial involvement, and their association with other autoimmune diseases. Compared with sporadic vitiligo probands, familial vitiligo probands have earlier age onset and longer disease duration. The prevalences of four autoimmune diseases namely rheumatoid arthritis, chronic urticaria, alopecia areata and psoriasis, were significantly elevated in generalized vitiligo probands and their first-degree relatives. The prevalences of chronic urticaria, rheumatoid arthritis, psoriasis were much higher in familial generalized vitiligo probands. In addition, the prevalences of diabetes mellitus and asthma were also higher in familial vitiligo probands. These findings indicate that generalized vitiligo may share common genetic aetiologic links with other autoimmune diseases, and the genetic component of familial generalized vitiligo is stronger.

(2E,5E)-2,5-Bis(3,4,5-trimethoxy-benzyl-idene)cyclo-penta-none

The title compound, C₂₅H₂₈O₇, was prepared by the base-catalysed reaction of 3,4,5-trimethoxy­benzaldehyde with cyclo­penta­none. The mol­ecule has crystallographic twofold rotation symmetry and adopts an E-configuration about the central olefinic bonds. The two benzene rings and the central cyclo­penta­none ring are almost coplanar [dihedral angle = 4.7 (2)°].

1,5-Dimethyl-4-[(E)-3-phenoxy-benzyl-ideneamino]-2-phenyl-1H-pyrazol-3(2H)-one

The title Schiff base, C₂₄H₂₁N₃O₂, adopts an E configuration with respect to the central C=N bond. The pyrazole ring and the central benzene ring attached to the imino group are almost coplanar. The phenyl ring attached to the pyrazole unit is twisted by 39.3 (2)° with respect to the pyrazole ring plane. The phen­oxy benzene ring makes a dihedral angle of 79.8 (2)° with the central benzene ring.

Changes of endotoximia, cytokines and nitric oxide and therapeutic effects of sandostatin in rats with severe acute pancreatitis

AIM: To study the roles of endotoximia, cytokines and nitric oxide in the development of severe acute pancreatitis (SAP) and the therapeutic effects of sandostatin (SS) in rats.

METHODS: SAP models were induced by retrograde injection of 15 g/L sodium deoxycholate and then treated by SS. The plasma levels of endotoxin (ET), lipid peroxide (LPO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and nitric oxide (NO), as well as the expression LPO, TNF-α, IL-6 and NO in pancreatic tissues, were measured. The changes of pancreatic histology were examined under light microscope.

RESULTS: As Compared with those in sham operation group, the plasma levels of ET, LPO, TNF-α, IL-6 and NO were markedly higher in SAP group (P < 0.01), and the changes of ET, LPO, TNF-α and NO at 6 h were higher (898 ± 114 EU/L, 24.58 ± 1.23 μmol/L, 246.3 ± 16.5 ng/L, 162.8 ± 10.9 mmol/L, P < 0.05) than those at 12 and 24 h. The changes of LPO, TNF-α, IL-6 and NO in pancreatic tissues of SAP group were obviously higher in comparison with those of sham group (3.31 ± 0.85 μmol/g vs0.33 ± 0.04 μmol/g, P < 0.01; 2.57 ± 0.14 ng/g vs 0.16 ± 0.04 ng/g, P < 0.01; 85.6 ± 24.6 ng/g vs 32.5 ± 5.7 ng/g, P < 0.01; 15.3 ± 1.2 mmol/g vs 6.6 ± 1.4 mmol/g, P < 0.01); and severe damages of pancreatic tissues were observed under light microscope. In SAP group, the plasma levels of LPO, TNF-α, IL-6 and NO were significantly correlated with ET level (r = 0.858,P < 0.01; r = 0.958, P < 0.01; r = 0.918, P < 0.01; r = 0.875, P < 0.01). The indexes mentioned above in SS group were obviously ameliorated in comparison with those in SAP group (P < 0.01).

CONCLUSION: Endotoximia, cytokines and NO play important roles in the development of severe acute pancreatitis. Sandostatin can block the chain reaction caused by these factors.

Diode-laser tomography for arcjet plume reconstruction

Diode-laser absorption tomography is described with which the spatial temperature and the atomic number density distribution of a 3-kW class arcjet can be derived simultaneously by reconstruction of the absorption coefficient field of the arcjet's argon exhaust plume. One can perform various parameter measurements by changing the arcjet's mass-flow rates and discharge currents. The maximum temperature and atomic number density increase with the mass-flow rate and the discharge current. The trend for increase is not always found for a specific input power, although at a fixed mass-flow rate the power increases at that rate.

Enantioselective Michael addition of nitromethane to alpha, beta-enones catalyzed by chiral quaternary ammonium salts. A simple synthesis of (R)-baclofen

[reaction:see text] Enantioselective Michael addition of nitromethane to an alpha, beta-enone is a key step in the synthesis of (R)-baclofen.

Highly enantioselective Michael reactions catalyzed by a chiral quaternary ammonium salt. Illustration by asymmetric syntheses of (S)-ornithine and chiral 2-cyclohexenones

[formula: see text] The use of the chiral quaternary ammonium salts 1a and 1b makes possible enantioselective Michael reactions which have been applied to the asymmetric syntheses of (S)-ornithine (2) and the chiral 2-cyclohexenone 6.

Mechanism and conditions for highly enantioselective epoxidation of alpha,beta-enones using charge-accelerated catalysis by a rigid quaternary ammonium salt

[formula: see text] Highly enantioselective (up to 130:1) epoxidation of a variety of alpha,beta-enones to form alpha,beta-epoxy ketones is described along with a rational analysis of the mechanistic basis for this strong absolute stereochemical control by the chiral catalyst 2.

Diagnostics of an argon arcjet plume with a diode laser

The diode-laser absorption technique was applied for simultaneous velocity and temperature measurements of an argon plume exhausted by an arcjet. The Ar I absorption line at 811.531 nm was taken as the center absorption line. The velocity and the temperature were derived from the Doppler shift in the absorption profiles and the full width at half-maximum of the plume absorption profile, respectively. From the measured plume velocity and temperature, the total enthalpy of the exhausted plume, the thrust efficiency, and the thermal efficiency of the arcjet were derived, and the performance of the arcjet was examined. The results are demonstrated to agree with results derived by other methods, and the technique can be applied to the measurement of other arcjet systems without much modification.

[Conservative therapy of combining laparoscopy and Chinese medicine for ectopic pregnancy]

44 cases of ectopic pregnancy have been treated conservatively by combining laparoscopy with TCM and all were successful. After confirmatory diagnosis was made under laparoscope low dose (5-15mg) of Methotrexate (MTX) was injected into tubal swelling, as well as taking modified Huo-Luo-Xiao-Ling Dan orally and using Ding-Tong paste and Zi-Gong pill externally, it not only improved the function of herbal medicine that was not potent enough to kill active embryo, but also gave full play of TCM which could remove stasis and masses by promoting blood circulation to assist in killing the embryo. The successful rate (100%) of combined therapy was significantly higher than that (78.2%) of control group (using TCM only, P < 0.01). Comparing with the two groups in successful cases, the mean serum hCG concentrations per day of combined therapy lowered faster than that of control group (P < 0.005), the mean time of abdominal pain disappearance and hospitalized period of combined group were shorter (P < 0.01). In a word, this combined therapy is a simple and safe method which could preserve reproductive function to the maximum.

[Effect of liuwei dihuang granules, pills and decoction on contents of cAMP, E2, T, Zn and Cu in plasma of renal yin deficient patients]

Experiments showed that in patients of renal yin deficiency who took orally Liuwei Dihuang granules for 4 weeks, the contents of cAMP, E2, Zn and Cu were found mankedly lower, but the contents of T mankedly higher than before using the drugs. This indicates that the granules are equally effective as pills and decoction.

Cadmium exposure and health effects among residents in an irrigation area with ore dressing wastewater

About 0.05 mg Cd l-1 was found in the irrigation water contaminated by the wastewater discharged from tungsten ore dressing plants, and about 1 mg Cd kg-1 was found in irrigated acid soils. The main sources of cadmium intake by residents of the polluted areas are agricultural products. The average intake of cadmium was 367-382 micrograms day-1, and for smokers 417 micrograms day-1. Among the residents who have been exposed to cadmium for more than 25 years, cadmium absorption (urinary cadmium greater than or equal to 10 micrograms g-1 creatine) was 60% and an early effect on the target organ (urinary cadmium greater than or equal to 15 micrograms g-1 creatinine and urinary beta 2-microglobulin greater than 500 micrograms g-1 creatinine) was detected in 17% of the sample of 433 persons. Levels of urinary cadmium and blood cadmium exceeded the critical value in the exposed group. The concentrations of urinary calcium, beta 2-microglobulin and N-acetyl-beta-D-glucosaminidase were significantly higher in residents of contaminated areas than in those of control areas. Case-control study of the residents shows that many have suffered from a nephropathy with tubulo-interstitial abnormalities. Owing to the combined cadmium effect, the cases with fractional beta 2-microglobulin excretion greater than 0.10 were 46% in the exposed population, and were much higher than that in the control group (20.3%).