Transforming Growth Factor-β1 Gene Polymorphisms and Bone Turnover,Bone Mineral Density and Fracture Risk in Southern Chinese Women

Genetic contributions play an important role in determining bone mineral density (BMD) and bone turnover. Transforming growth factor- (TGF-) is abundant in bone and has been implicated as an important regulator of both bone formation and resorption. Several polymorphisms of the TGF-1 gene have recently been suggested to be associated with BMD and susceptibility to osteoporotic spine fractures. To determine the relationship between TGF-1 polymorphisms and BMD in southern Chinese women, three SNPs at C^–1348-T, T²⁹-C, and T^861-20-C of TGF-1 gene were analyzed in 237 postmenopausal southern Chinese women by RFLP and direct sequencing. BMD at the lumbar spine and hip region, biochemical markers of bone turnover, as well as serum levels of TGF-1 were measured. Only the T²⁹-C polymorphism of TGF-1 gene was associated with BMD and fracture risk. The prevalence of fragility fractures was significantly higher in individuals with TC genotype (P < 0.05). Serum alkaline phosphatase and osteocalcin levels as well as urinary N-telopeptide excretion were significantly higher in women with TC than with TT or CC genotypes, and the difference remained significant after adjusting for age and BMI (all P < 0.05). Women with TC genotype had lower BMD at the trochanteric (P < 0.03) and total hip region (P = 0.05). No difference was observed in the serum TGF-1 levels among the three genotypes. In conclusion, an association between T²⁹-C polymorphisms of TGF-1 gene and BMD, bone turnover as well as fragility fractures were demonstrated in postmenopausal southern Chinese women.     

The association between transforming growth factor-β gene promoter C-509T polymorphism and Chinese children with Henoch-Schönlein purpura

Many cytokines, including transforming growth factor- (TGF-) and tumor necrosis factor- (TNF-), are involved in the inflammatory process of Henoch-Schönlein purpura (HSP). The objective of this study was to investigate whether TGF- C-509T and TNF- G-308A polymorphisms are associated with childhood HSP. The loci of interest were amplified from genomic DNA using specific primers and polymerase chain reaction, and these two polymorphisms were compared between Chinese children with HSP and healthy controls. The disease severities evaluated and expressed as symptom score of patients with different genotypes were also compared. The TGF- -509 TT genotype was more common in children with HSP than controls (31% vs. 8%, P =0.03, odds ratio=4.95). The allelic frequencies of TGF- -509, genotypic and allelic frequencies of TNF- -308 were not significantly different. Patients with the TT genotype had more severe clinical presentations than non-TT (TC+CC) patients (4.1±0.42 vs. 2.7±0.31, P =0.018). These results suggest that the TT genotype of the C-509T polymorphism of the TGF- gene might be related to the susceptibility of Chinese children to HSP and to the severity of this disease.     

Association and Linkage Disequilibrium Analyses Suggest Genetic Effects of Estrogen Receptor α and Collagen IA1 Genes on Bone Mineral Density in Caucasian Women

Estrogen receptor alpha (ER) and collagen IA1 (COLIA1) genes have been suggested as possibly implicated in reduced bone mineral density (BMD). The present study investigated the occurrence of association and linkage disequilibrium between radiographic hand BMD and polymorphic alleles of ER and COLIA1 genes, in human pedigrees of a Chuvasha population in Russia. The study sample included 463 members of 113 pedigrees, mostly nuclear families. We performed association and transmission disequilibrium test (TDT) analyses of the combined PvuII and XbaI RFLPs alleles on the same chromosome (haplotype) of the ER gene with BMD Z scores of cancellous or cortical bone in the hand phalanges. The association analyses were performed separately for both genders in the parental generation, i.e., fathers (n = 114; average age 64.2 y) and mothers (n = 122; average age 62.7 y). The Px haplotype was associated significantly with lower BMD Z scores in mothers only. The difference between subjects who carried one or two copies of the Px haplotype and those lacking it was 0.68 Z scores, P = 0.003 and 0.51 Z scores, P = 0.025 for cancellous and cortical bone, respectively. Multiple linear regression model with age, height, weight, and Px haplotype status as predictors explained 26.7% and 28.3% of the total observed variance in BMD with Px haplotype as independent predictor explaining 5.9%; P = 0.002 and 3%; P = 0.028 (cancellous and cortical bone, respectively). Results of t-TDT for triads of two parents and just one of their female offspring (but not male offspring) suggested the existence of linkage disequilibrium between the two loci of Px haplotype and BMD trait (P = 0.047). No association was found between polymorphic alleles of COLIA1 gene and BMD, but mothers with combined genotypes of Px haplotype of ER gene and s allele of COLIA1 gene had the lowest mean Z scores (–0.944 and –0.788 for cancellous and cortical bone, respectively). We conclude that the Px haplotype of the ER gene is associated with low BMD values in females, as the phenotype is gender dependent (the association was not observed in males), and the s allele of COLIA1 gene in combination with this haplotype contributes to reduced BMD.     

Bone mineral density in women with sarcoidosis

Sarcoidosis is a multisystem granulomatous disease of unknown etiology. Almost any organs of the body, but mostly the lungs, are involved. Bone mineral density (BMD) can be affected directly or indirectly in chronic granulomatous systemic diseases such as sarcoidosis. The aim of our study was to evaluate BMD in premenopausal and postmenopausal sarcoidosis patients with or without prednisone treatment and to compare their BMD values with those of a control group having the same menopausal status. Thirty-five premenopausal women (18 untreated, 8 treated, and 9 controls) and 21 postmenopausal women (5 untreated, 5 treated, and 11 controls) were included in the study. All of the patients had a histologically proven diagnosis and were being followed-up at the Sarcoidosis Outpatient Clinic of our unit. BMD of the lumbar (L) spine and femoral neck was measured by dual-energy absorptiometry (DEXA). The subgroups of premenopausals and postmenopausals were compared separately. Comparison among the groups was performed by using analysis of variance. Age, duration of the disease, and body mass index were comparable in treated, untreated, and control subgroups of the pre- and postmenopausal groups, and the subgroups of postmenopausals had comparable durations since menopause. For premenopausals, BMD values at L1–4 were not significantly different among the subgroups (0.920 ± 0.08g/cm², 0.801 ± 0.09g/cm², and 0.910 ± 0.05g/cm², for untreated, treated, and controls, respectively). However, the BMD value at the femoral neck in treated patients (0.921 ± 0.1g/cm²) was significantly lower than the values in untreated patients (1.080 ± 0.2g/cm²; P 0.01) and in controls (1.028 ± 0.17g/cm²; P 0.05). For postmenopausals, the BMD value at L1–4 in controls (1.019 ± 0.07g/cm²) was significantly higher than the values in untreated patients (0.783 ± 0.01g/cm²) and in treated patients (0.751 ± 0.08g/cm²; P 0.001 for both). The BMD value at the femoral neck in controls (0.890 ± 0.1g/cm²) was higher than the values in untreated patients (0.745 ± 0.08g/cm²) and treated patients (0.747 ± 0.1g/cm²), but the difference was not statistically significant (P = 0.06). We concluded that sarcoidosis patients, especially postmenopausal patients with corticosteroid treatment, may have an increased risk of bone mineral loss. Large-scale studies are warranted in order to delineate the exact roles of the disease itself, menopausal status, and corticosteroid treatment in this bone mineral loss.     

Serum Levels of Tissue Inhibitor of Metalloproteinases-1 (TIMP-1) in Colorectal Cancer Patients

Purpose Expression of tissue inhibitor of metalloproteinases (TIMP)-1 in colorectal cancer tissue is known to be related to disease progression; however, the clinical significance of measuring the blood level of TIMP-1, which we evaluate herein, has not yet been clarified.Methods The serum level of TIMP-1 was measured by a one-step enzyme immunoassay in 123 patients who underwent resection of primary colorectal cancer.Results An elevated level of serum TIMP-1 was associated with advanced Dukes stage (P = 0.03), greater diameter of the primary tumor (P = 0.03), more lymph node metastasis (P = 0.04), and liver metastasis (P 0.001). There was a weakly positive correlation between the serum carcinoembryonic antigen (CEA) level and the serum TIMP-1 level. In patients who underwent potentially curative resection, the disease-free survival was not different between those with a high TIMP-1 level (203.5ng/ml, n = 32) and those with a low TIMP-1 level (203.5ng/ml, n = 66, P = 0.62). In patients with Dukes stage D cancer who underwent noncurative resection, the survival times were not different between those with a high TIMP-1 level (n = 13) and those with a low TIMP-1 level (n = 10, P = 0.20).Conclusions Elevated levels of serum TIMP-1 reflect the extent of colorectal cancer, without a close correlation with the serum CEA level. These findings suggest that measuring the serum TIMP-1 level would not help to predict the prognosis of patients with colorectal cancer.     

pQCT bone strength index may serve as a better predictor than bone mineral density for long bone breaking strength

Bone mineral density (BMD) is commonly used to predict osteoporotic fracture risk without considering the geometry of the bone. However, geometric parameters are also important in determination of bone strength. An index including both material and geometric properties may be therefore more relevant in prediction of fracture risk. We studied the correlation between parameters measured by noninvasive peripheral quantitative computed tomography (pQCT) and bone bending strength of the diaphysis of 45 fresh goat humeri and 27 femora. Multislice pQCT was used for measuring volumetric diaphyseal cortical BMD, total BMD, diaphyseal and cortical cross-sectional area (CSA), and cross-sectional moment of inertia (CSMI) and their derived bone strength indices (BSIs), including BSI_CSMI (cortical BMD × CSMI) and BSI_CSA (cortical BMD × cortical CSA). Conventional dual-energy absorptiometry (DXA) was also conducted to measure areal BMD of diaphysis for comparison. Ultimate fracture load was obtained via three-point bending test. Results showed that for femora, fracture load was correlated better with BSI_CSA (r = 0.697, P 0.001) than cortical BMD (r = 0.304, P 0.05) and total BMD (r = 0.387, P 0.05) measured using pQCT and areal BMD (r = 0.612, P 0.001) measured using DXA. For humeri, fracture load was also correlated with BSI_CSA (r = 0.579, P 0.001) but not with other pQCT parameters including cortical BMD and total BMD (r = 0.282 and 0.305, respectively; P 0.05, both). The best correlation was found with areal BMD measured by DXA (r = 0.760, P 0.001). In conclusion, pQCT noninvasive BSI_CSA derived from cortical BMD (material) and its cortical CSA (bone geometry or distribution) may serve as an important noninvasive index for predicting long bone bending strength. The bending strength was also predicted by bone mass (areal BMD) measured by DXA, an integration of bone mineral and geometry. Further clinical studies are needed to validate the predictive value of BSI in long bone osteoporotic fracture.     

Bone Mineral Density of the Lumbar Spine is Associated with TNF Gene Polymorphisms in Early Postmenopausal Japanese Women

We investigated the relationships between tumor necrosis factor (TNF) gene polymorphism, circulating TNF-alpha (TNF-) concentrations, and bone mineral density (BMD) in the lumbar spine. TNF gene polymorphisms studied were the Nco I polymorphism within the first intron of TNF-beta (TNF-) and three single nucleotide polymorphisms in the promoter region of the TNF- gene, at positions –857, –863, and –1031. Allelic variants of the TNF gene were identified using restriction fragment length polymorphism (RFLP) analysis in 177 postmenopausal Japanese women within 10 years after menopause, aged 56.4 ± 4.5 years (mean ± SD). A significantly higher prevalence of the alleles TNF--863A (20.3% versus 9.9%) and TNF--1031C (21.3% versus 12.4%) was seen in the low BMD group (Z-score < 0, n = 91) than in the high BMD group (0 Z-score, n = 86). In genotype analysis, although difference did not reach a significant level, women with the rarest allelic variants, i.e., homozygous TNFb1, TNF--863A, and TNF--1031C, showed the lowest BMD Z-scores. Women with another rarest allelic variant, TNF--857T/T had significantly lower BMD Z-scores than did women with TNF--857C/T or –857C/C. The BMD Z-score decreased significantly with an increase in the total number of such rare alleles. Serum concentrations of TNF- did not differ significantly among groups divided by genotypes. Multiple linear regression analysis revealed that the total number of rare alleles, in addition to the body mass index and the number of years since menopause, was an independent predictor of the BMD. These presumptive functional polymorphisms of the TNF gene may be associated with the lumbar spine BMD in early postmenopausal Japanese women.     

Association of vitamin D and estrogen receptor gene polymorphism with the effects of longterm hormone replacement therapy on bone mineral density

We longitudinally studied whether vitamin D receptor (VDR) and estrogen receptor (ER) gene polymorphisms in Japanese women influenced the effect of longterm hormone replacement therapy (HRT) on bone mineral density (BMD) in the lumbar spine. The 81 subjects were aged 40 to 64 years (mean ± SEM, 49.5 ± 0.6 years), and had received sequential or continuous HRT regimens, including 0.625mg of conjugated equine estrogen and 2.5 to 5mg of medroxy-progesterone acetate, for at least 3 years. Genomic DNA was extracted from blood cells, and analyzed for restriction fragment length polymorphism, using the restriction endonucleases Taq I, Apa I, and Fok I for VDR, and Pvu II and Xba I for ER. At 1 year, subjects with a Taq I genotype of TT (i.e., site absent) showed a significantly greater increase in BMD with treatment (BMD) than subjects with the Tt genotype (2.6 ± 0.5% vs –0.8 ± 1.4%; P = 0.016). A small difference between genotypes remained at 2 years (3.8 ± 0.6% vs 0.8 ± 1.6%; P = 0.069), but no significant difference between genotypes was seen at 3 years. In multiple regression analyses, BMD at 1 year was significantly affected by VDR-Taq I, Apa I, and ER-Pvu II genotypes and by age at treatment initiation, although at 3 years or more, BMD was significantly affected only by age. These results indicate that Taq I VDR gene polymorphism predicted the effect on lumbar BMD for the first year of HRT in Japanese women, and that the differences in BMD versus the polymorphism disappeared if the treatment was continued for over 2 years.     

Comparison of anesthetic effects of epidural and intravenous administration of buprenorphine during operation

Thirty six patients were received epidural anesthesia with or without buprenorphine (BPN) during upper abdominal surgery. They were divided into three groups of 12 patients as follows; G-I received 20ml of 1% lidocaine epidurally, G-II received 20ml of 1% lidocaine epidurally and 0.6mg BPN intravenously, G-III received 20ml of 1% lidocaine with 0.6mg BPN epidurally. Additional 5ml of 1% lidocaine was given to any patient if systolic blood pressure or heart rate increased 10% compared to control value. Trachea was intubated following anesthetic induction with thiopental. The lungs were ventilated with a mixture of N₂O/O₂ (33%) and pancuronium was used for muscle relaxation. The total required doses of lidocaine in G-II and G-III were decreased 60% compared to control group (G-I) (P 0.05). The mean period of time until the first administration of pentazocine for postoperative pain was 13 ± 10hr (mean ± SD) in G-II and 19 ± 24hr in G-III compared to 5 ± 4hr in G-I (P 0.001). The dose of the administration of pentazocine that was required for pain relief during the first 48 postoperative hr in G-III was 54 ± 10mg (mean ± SD) compared to 150 ± 21mg in G-I (P 0.02) and 106 ± 28mg in G-II (P 0.05). Recovery from anesthesia in G-III was more rapid than that in G-I (P 0.05). The Pa_{CO 2} values in G-II and G-III increased 15% compared to control group at about 4hr and 8hr after administration of BPN, but any clinical treatment was not needed for them. Nonrespiratory side effects, e.g., nausea, vomiting, fatigue and headache, were comparably common in all groups. Mild hematuria associated with acute hypotension occurred in two patients in G-II (17%) immediately after the intravenous injection of 0.6mg of BPN. The results showed that 0.6mg of BPN given epidurally demonstrated better anesthetic and more potent postoperative analgesic effects and lesser side effects than 0.6mg of BPN given intravenously in patients undergoing upper abdominal surgery.(Yonemura E, Fukushima K.: Comparison of anesthetic effects of epidural and intravenous administration of buprenorphine during operation. J Anesth 4: 242–248, 1990)     

Serum levels of alpha-1 microglobulin and beta-2 microglobulin in bone marrow transplant recipients treated with cyclosporin A

The levels of alpha-1 microglobulin ( ₁m) and beta-2 microglobulin ( ₂m) in serum were estimated in 77 bone marrow transplant recipients. In comparison to pretransplant levels, the highest levels of ₁m and ₂m were found during impairment of renal function, i.e., during cyclosporin-induced nephrotoxicity and during treatment with other nephrotoxic drugs (P<0.001). The ₁m levels were less elevated during infections and acute graft-versus-host disease (P<0.01), while ₂m levels were markedly elevated during the same conditions (P<0.001). The linear correlations between serum creatinine and ₁m and creatinine and ₂m were r=0.7 and 0.8, respectively (P<0.001). The overall correlation between ₁m and ₂m was 0.4 (P<0.001). It is concluded that ₁m might be a complement to serum creatinine levels in monitoring renal function after bone marrow transplantation.     

Estrogen receptor alpha gene analysis in osteoporosis and familial osteoporosis

Estrogens are important determinants of bone mineral density (BMD) mediating their effects via estrogen receptor (ER) and (ER). The strong genetic predisposition to osteoporosis, and the fact that alterations in the aminoterminal region of ER have been linked to bone disturbances, prompted us to identify genetic alterations in exon 1 and exon 2 of ER in osteoporotic individuals. Sixty-two unrelated normal subjects (age 46.1±9.5 years) and 72 unrelated osteoporotic subjects (age 52.3±7.9 years) were studied. Their menopausal status was pre- and perimenopausal. We also included 30 related osteoporotic individuals (mother-daughter or sister-sister relationship) (age 46.2±12.8 years) belonging to 14 families who where also pre- and perimenopausal. DNA was extracted from peripheral blood, exons 1 and 2 were amplified by polymerase chain reaction (PCR) and were further submitted to denaturing gradient gel electrophoresis (DGGE), single stranded conformational polymorphism (SSCP), restriction fragment length polymorphism (RFLP) and sequence analysis. Bone turnover markers were also determined. Two polymorphisms were identified in exon 1 (codons 10 and 87) in both normal and osteoporotic women. Statistical analysis revealed no difference (P>0.05) in the ER genotype frequencies within osteoporotic families as compared with the same genotypes in the unrelated normal or osteoporotic subjects. Codon 10, codon 87 polymorphisms were not related to BMD or bone turnover markers. No other mutations were found in exons 1 and 2 in all subjects studied. Genetic alterations in exons 1 and 2 of ER are not associated to osteoporosis and familial osteoporosis. Moreover, the codon 10 and codon 87 polymorphisms do not seem to be correlated with BMD and bone turnover markers.     

Tetracycline double-labeling of iliac trabecular bone in 41 normal adults

Summary A histomorphometric evaluation of the iliac crest trabecular bone remodeling was performed after tetracycline double-labeling in 41 normal Danes (12 males and 29 females) aged 19 to 56 years. The fraction of formative (osteoid covered) and resorptive surfaces was unrelated to age but higher in males than in females (P<0.02 andP<0.05, respectively). The appositional rate (0.65±0.12 m/day) was unrelated to age and sex, whereas the fractional labeled surfaces were higher (P<0.01) in the males (0.18±0.08 m²/m²) than in the females (0.12±0.05 m²/m²), and among the females inversely related to age (R=–0.38,P<0.05). The bone formation rate at BMU level (0.50±0.20 m³/m²/day) was unrelated to sex, but among the females inversely related to age R=–0.49,P<0.01). The bone formation rate at tissue level was higher (P<0.02) in the males (0.13±0.07 m³/m²/day) than in the females (0.07±0.03 m³/m²/day) and among the females inversely correlated to age (R=–0.43,P<0.05). The age- and sex-dependent variations in the dynamic parameters underline the importance of a more elaborated normal material.     

APOE Haplotypes Influence Bone Mineral Density in Caucasian Males but Not Females

Low bone mineral density (BMD) is one of the most important risk factors for osteoporosis. Apolipoprotein E (APOE) has been considered as a candidate gene for osteoporosis because of its influence on osteoblast uptake of lipoprotein-borne vitamin K. Using the quantitative transmission disequilibrium test QTDT, we examined linkage and/or association of APOE and BMD at the lumbar spine and the total hip in a sample of 387 Caucasian nuclear families with 715 parents and 953 children. The children were aged 20–50 years and female offspring were premenopausal as well. Four single nucleotide polymorphisms (SNP1-4) in the APOE gene, 4-locus haplotypes and 2-locus haplotypes (1, 2, 3, 4 isoforms, reconstructed by SNP3 and SNP4) were analyzed. In the whole sample and the female offspring families we found no evidence of linkage or association for either single SNP or haplotype with BMD at the two studied skeletal sites. In the male offspring families, within-family associations were observed at the haplotypes CGTC (P = 0.001), GGTT (P = 0.002), and GATC (P = 0.006) for the lumbar spine BMD, and GATC (P = 0.008) for the total hip BMD. These data suggested that in our studied Caucasian population, APOE may have effects on BMD variation in males but not females. Further studies with a larger sample size are required to confirm such results.     

The Risk of Colles’ Fracture is Associated with the Collagen I Alpha1 Sp1 Polymorphism and Ultrasound Transmission Velocity in the Calcaneus Only in Heavier Postmenopausal Women

To compare the ability of the bone mineral density (BMD) at the distal forearm, collagen I alpha 1 (COLIA1) polymorphism, and ultrasound stiffness to identify individuals with increased risk of wrist fracture, we studied 183 postmenopausal Czech women with a wrist fracture and 178 postmenopausal controls, ages 45–70 years. The genotypes Ss and ss were significantly overrepresented among fracture cases. The BMD measurements at the femoral neck, total femur, and distal forearm as well as ultrasound stiffness of the heel, broadband ultrasound attenuation (BUA), and speed of sound (SOS) were significantly lower in the fracture cohort. BMD of the distal forearm was the main determinant of susceptibility to the wrist fracture. Weight, the COLIA1 genotype, and ultrasound SOS further strengthened the predictive value of BMD. However, we found interaction between weight and both the COLIA1 Sp1 polymorphism and ultrasound parameters. Presence of the s allele as well as low SOS acted as significant predictors of wrist fracture only in heavier women, (62 kg) but not in women with a body weight of less than 62 kg. In heavier women, both the COLIA1 Sp1 polymorphism and ultrasound parameters acted as independent markers that contributed to BMD to enhance fracture prediction. However, the COLIA1 enabled a higher specificity (specificity 72.4%, sensitivity 44.2%), whereas SOS enabled a higher sensitivity (sensitivity 73.9%, specificity, 45.7%). We conclude that BMD at total forearm, the COLIA1 polymorphism, and ultrasound SOS are independent predictors of wrist fracture in postmenopausal women. The effect of the COLIA1 Sp1 polymorphism and SOS on wrist fracture risk is more pronounced in patients with a higher body weight.     

Analgesic dose-response relation in cervical epidural block

The relationship between the age and the spread of analgesia from different epidural anesthetic doses was examined by studying analgesic dose responses in cervical epidural analgesia. Two different anesthetic doses (5ml or 10ml) of 2% mepivacaine were injected into the cervical epidural space at a constant pressure (80mmHg) using an intravenous apparatus, and the spread of analgesia to pinprick was assessed. The significant correlation was found between the patients age and the number of spinal segments blocked (5ml:r = 0.8498, P < 0.01, 10ml:r = 0.5988, P < 0.01). The inverse linear relationship was found between the patients age and the segmental dose requirement (5ml:r = –0.6754, P < 0.01, 10ml:r = –0.5784, P < 0.01). Patients under 39 years of age showed a direct relationship between the dose injected and the number of spinal segments blocked, enabling prediction of the number of segments blocked with a given dose of local anesthetic. Doubling the epidural dose approximately doubled the number of spinal segments blocked. The analgesic dose-response relation in patients over 60 years of age differed from that in patients under 39 years of age and doubling the epidural dose did not double the number of spinal segments blocked. Progressively more extensive analgesia was obtained from a given dose of local anesthetic with advancing age. It was difficult to limit the extent of analgesia by injecting a smaller dose of local anaesthetic in the elderly.(Hirabayashi Y, Matsuda I, Inoue S et al.: Analgesic dose-response relation in cervical epidural block. J Anesth 2: 22–27, 1988)     

The N-Methyl-D-aspartate (NMDA) receptor antagonist dizocilpine (MK-801) suppresses enfturane-induced opisthotonus in mice

We determined whether enflurane-induced opisthotonus in ddN mice is mediated by N-methyl-D-aspartate (NMDA) receptor using NMDA receptor antagonists dizocilpine (MK-801) and ketamine. Animals were given intraperitoneal injections of 0.2ml saline (control), 2.5 or 5.0mg·kg^–1 dizocilpine in saline, or 20 or 40mg·kg^–1 ketamine is saline 20min prior to exposure to 2.0% enflurane. Incidence of opisthotonus measured during exposure to enflurane for 20min was 49% (n = 51) in saline (control) group, 6.7 (P 0.01 vs control, n = 30) and 15.0% (P 0.01, n = 40) in 2.5 and 5.0mg·kg^–1 dizocilpine group, respectively, and 43.9 (NS, n = 41) and 40.0% (NS, n = 40) in 20 and 40mg·kg^–1 ketamine group, respectively. These results strongly suggest that enflurane-induced opisthotonus is mediated by NMDA receptor. Ketamine failed to suppress significantly due to possibly small dosages. Further, dizocilpine itself produced severe seizures during preenflurane period (30.0 and 40.0% in 2.5 and 5.0mg·kg^–1, respectively), which may be a novel finding.(Komatsu H, Nogaya J, Anabuki D, et al.: The N-methyl-D-aspartate (NMDA) receptor antagonist dizocilpine (MK-801) suppresses enflurane-induced opisthotonus in mice. J Anesth 7: 519–522, 1993)     

Cyclooxygenase-2 Inhibition Improves Macrophage Function in Melanoma and Increases the Antineoplastic Activity of Interferon γ

Background: Melanoma inhibits macrophage tumoricidal activity and increases the expression of cyclooxygenase-2 (COX-2). In this study, we sought to determine whether inhibition of COX-2 could restore macrophage function and hence maximize the antitumor activity of the immune stimulant interferon (IFN).Methods: Peritoneal macrophages were exposed to B16 melanoma-conditioned medium for 24 hours with or without the COX-2 inhibitor NS-398 and then were stimulated with lipopolysaccharide and IFN. Cytotoxic activity, nitrite production, and cytokine production by the stimulated macrophages were measured. In addition, B16 melanoma cells were implanted intradermally into mice treated with IFN (14,000 U on alternate days) alone or with a combination of IFN and a COX-2 inhibitor (NS-398 or nimesulide). Mice were assessed for tumor growth and survival.Results: Macrophage cytotoxicity and nitrite production were significantly suppressed by melanoma-conditioned medium (P < .01). This was prevented by 200 M of NS-398 (P < .05). In vivo, combined treatment with IFN and a COX-2 inhibitor caused a significant inhibition of tumor growth (P < .01) and improved survival (P = .02) compared with controls.Conclusions: COX-2 inhibition reversed melanoma-induced suppression of macrophage function, and combined treatment of IFN plus a COX-2 inhibitor was maximally effective in reducing tumor growth and improving survival.     

ACE inhibition modulates transforming growth factor-β receptors in the young rat

The renin-angiotensin system plays an important role in renal growth and development. Exposure of the neonate to angiotensin converting enzyme (ACE) inhibitors increases mortality and results in growth retardation and abnormal renal development. It has been demonstrated that ACE inhibition in the developing kidney reduces the renal expression of growth factors, which may account for renal growth impairment. This study was designed to investigate the relationship between renal growth impairment and the expression of transforming growth factor-1 (TGF-1), TGF- receptor I [TRI, activin-like kinase (ALK)-1 and ALK-5], and TGF- receptor II (TRII). Newborn rat pups were treated with enalapril (30 mg/kg per day) or vehicle for 7 days, and kidneys were removed for Western blotting of TGF-1, ALK-1, ALK-5, and TRII, and for RT-PCR of ALK-5 and TRII. TGF-1, ALK-1, ALK-5, and TRII were also detected by immunohistochemistry. Enalapril treatment resulted in an increased mortality (30.4%) by day 7, and reduced body weight and kidney weight (P<0.05 versus vehicle). Enalapril decreased renal TGF-1, ALK-1, and ALK-5 protein expression (P<0.05). Also, enalapril decreased ALK-5 mRNA expression (P<0.05). TRII expression was not changed by enalapril treatment. These results indicate that ACE inhibition in the developing kidney decreases TGF-1, ALK-1, and ALK-5 expression, which may account for renal growth impairment. TRII may not be modulated by ACE inhibition in the developing kidney.     

The echocardiographic assessment of left ventricular performance during sevoflurane and halothane anesthesia

The cardiovascular effects of sevoflurane were studied and compared with those of halothane in 30 healthy patients. The patients were assigned to receive 1MAC sevoflurane (n = 10), 2MAC sevoflurane (n = 10) or 1MAC halothane (n = 10) in N₂O 2l·min^–1 and O₂ 4l·min^–1. The changes in left ventricular diastolic and systolic dimension (Dd and Ds), fractional shortening (FS), mean velocity of circumferential fiber shortening (mVcf), left ventricular diastolic and systolic volume (Vd and Vs), stroke volume (SV), ejection fraction (EF) and cardiac index (CI) were evaluated by echocardiography. Sevoflurane produced significant dose-dependent decreases in FS, mVcf, EF and SV, but no significant changes in Dd and Vd. Therefore, the decrease in SV was due mainly to the increase in left ventricular residual volume (Vs). One MAC halothane produced a more significant decrease in FS, mVcf, EF and SV, when compared to values obtained at 1MAC sevoflourane (P 0.01). CI was more significantly decreased with 1MAC halothane than with 1MAC and 2MAC sevoflurane (P 0.01). This was brought about by a slight decrease in HR with halothane and a slight increase in HR with sevoflurane, in addition to a smaller decrease in SV with sevoflurane than with halothane. This study suggests that sevoflurane may better preserve cardiac function as a pump in healthy patients, when compared to halothane.(Kasuda H, Akazawa S, Shimizu R.: The echocardiographic assessment of left ventricular performance during sevoflurane and halothane anesthesia. J Anesth 4: 295–302, 1990)     

Association of Estrogen Receptor α and Vitamin D Receptor Gene Polymorphisms with Bone Mineral Density in Chinese Males

Osteoporosis is a common health problem not only in females but also in males, however, studies of osteoporosis in males are relatively rare compared to those in females. This is especially true in genetics studies. We evaluated the effects of PvuII and XbaI polymorphisms in the estrogen receptor (ER-) gene and ApaI polymorphism in the vitamin D receptor (VDR) gene on BMD variation in a random sample of 352 unrelated males from 401 Chinese nuclear families. BMD was measured at the lumbar spine (L1–L4) and hip (femoral neck, trochanter, intertrochanteric region). Raw BMD values were adjusted by age, age², height, and weight as covariates. We found no significant results for the 3 individual markers on BMD variation, however, ER- haplotype analyses yielded some interesting results. Carriers of haplotype pX had a 4.98% lower BMD at the trochanter (P = 0.02) and 3.55% lower BMD at the lumbar spine (P = 0.09) than non-carriers. PX subjects had a 3.42% higher BMD at the trochanter and 3.26% higher BMD at the lumbar spine than others (P = 0.07 and P = 0.10, respectively). Such results were highly comparable with the significant or nearly significant interactions between ER-PvuII and ER-XbaI on BMD values at the trochanter (P = 0.03) and spine (P = 0.11). No significant results were observed for the interactions between ER-PvuII and VDR-ApaI, between ER-XbaI and VDR-ApaI, and between any of ER- haplotypes and VDR-ApaI locus. Our results suggest that the ER- haplotypes, not individual markers, may be associated with BMD variation at some skeletal sites in our Chinese male samples.