Patterns of physical activity in free-living adults in the Southern United States

OBJECTIVE

To examine the relationship between the amount and patterns of physical activity (PA), body fatness, and age in a heterogeneous adult population in the free living.

DESIGN

Cross-sectional study of the amount of PA over a 1-week period. The amount of body movements during PA (PA counts*10(3)) and time spent on various PA intensity categories were calculated from a triaxial accelerometer and compared with subject characteristics, including body fat from hydrodensitometry.

PARTICIPANTS

Adult healthy men (n=48) and women (n=72) were recruited from the Nashville, Tennessee area and their PA was monitored in their free-living environment.

RESULTS

The average weekday PA counts (176.5+/-60.3, P=0.002, r(2)=0.294), PA counts day-to-day variability (47.3+/-32.7, P=0.002, r(2)=0.286), daily maximum PA counts (241.9+/-89.2, P=0.001, r(2)=0.327), minute-to-minute variability on weekdays (0.281+/-0.091, P=0.001, r(2)=0.362), and the difference between maximum and minimum daily PA counts (130.6+/-78.3, P=0.008, r(2)=0.243) were significantly and negatively correlated with body fatness. During awake time, both men and women spent 10-12 h on low intensity (1.0-2.9 metabolic equivalents (METs)) PA, approximately 1 h on moderate (3.0-5.9 MET), and less than 10 min on vigorous (>6.0 MET) PA each day. On weekends, men and women spent more time at rest (1 MET), less time on low-intensity PA, and men spent more time on moderate PA than on weekdays.

CONCLUSIONS

In adults living in the Southern US the amount of free-living PA was negatively correlated with body fatness. Both men and women spent the majority of active time on low and moderate PA. PA patterns on weekends were different than on weekdays and were related to sex and age, but not to body fatness.

SPONSORSHIP

National Institutes of Health, US.

The effect of Nb addition on mechanical properties, corrosion behavior, and metal-ion release of ZrAlCuNi bulk metallic glasses in artificial body fluid

Bulk metallic glasses (BMGs) of Zr(65 - x)Nb(x)- Cu(17.5)Ni(10)Al(7.5) with Nb = 0, 2, and 5 at % were prepared by copper mold casting. Compression tests reveal that the two BMGs containing Nb exhibited superior strength and plasticity to the base alloy. The corrosion behavior of the alloys obtained was investigated in artificial body fluid by electrochemical measurements. It was found that the addition of Nb significantly enhanced the corrosion resistance of the Zr-based BMG, as indicated by a remarkable increase in corrosion potential and pitting potential. XPS analysis revealed that the passive film formed after anodic polarization was enriched in aluminum oxide and depleted in phosphate ions for the BMGs containing Nb, which accounts for the improvement of corrosion resistance. On the other hand, metal-ion release of different BMGs were determined in PPb (ng/mL) level with inductively coupled plasma mass spectrometry (ICP-MS) after being immersed in artificial body fluid at 37 degrees C for 20 days. It was found that the addition of Nb considerably reduced the ion release of all kinds of metals of the base system. This is probably attributed to the promoting effect of Nb on a rapid formation of highly protective film.

Substrate metabolism, nutrient balance and obesity development in children and adolescents: a target for intervention?

Obesity results from the organism's inability to maintain energy balance over a long term. Childhood obesity and its related factors and pathological consequences tend to persist into adulthood. A cluster of factors, including high energy density in the diet (high fat intake), low energy expenditure, and disturbed substrate oxidation, favour the increase in fat mass. Oxidation of three major macronutrients and their roles in the regulation of energy balance, particularly in children and adolescents, are discussed. Total glucose oxidation is not different between obese and lean children; exogenous glucose utilization is higher whereas endogenous glucose utilization is lower in obese compared with lean children. Carbohydrate composition of the diet determines carbohydrate oxidation regardless of fat content of the diet. Both exogenous and endogenous fat oxidation are higher in obese than in lean subjects. The influence of high fat intake on accumulation of fat mass is operative rather over a long term. Several future directions are addressed, such that a combination of increased physical activity and modification in diet composition, in terms of energy density and glycemic index, is recommended for children and adolescents.

Differential trafficking of the Niemann-Pick C1 and 2 proteins highlights distinct roles in late endocytic lipid trafficking

The cellular location of Niemann-Pick C2 protein (NPC2) in cultured human fibroblasts and Chinese hamster ovary cells was examined immunocytochemically and in living cells by expression of a functional red fluorescent protein chimeric analogue.

RESULTS

NPC2 is present in the lysosomes of both cholesterol-depleted and -replenished cells, unlike Niemann-Pick C1 protein (NPC1) which is recruited to late endosomes only upon uptake of low-density lipoprotein. With mobilization of cholesterol from lysosomes, immunocytochemical detection of NPC2 in lysosomes is greatly diminished, whereas NPC1 remains in the late endosomal compartment. We found a partial overlap in the trafficking and organellar sites of accumulation of NPC2 and NPC1. In living cells, NPC2 traffics with NPC1 in late endosomal tubules. However, in contrast to NPC1, which remains either in late endosomal vesicles and tubules or at the peripheries of cholesterol-laden lysosomes, NPC2 moves into the central core of lysosomes. Glycolipid analysis reveals that, in contrast to null mutant NPC1 cells, which accumulate GM2 ganglioside only at the plasma membrane, with no endocytic storage, absence of NPC2 protein in null mutant NPC2 cells does not block internalization of GM2 into endocytic vesicles. This difference in the cellular distribution of GM2 in NPC1 and NPC2 null mutants is the first report of a variation in the phenotypic expression of these genotypically distinct lesions.

CONCLUSION

We speculate that while NPC1 may play a major role in the sorting of glycolipids as well as cholesterol within the late endosomes, NPC2 primarily plays a role in the egress of cholesterol and, potentially, glycolipids from lysosomes. These proteins appear not to be integrated into a tightly bound biological complex, but rather represent separate functional entities that complement each other.

Body size and early growth in appropriate- and large-for-gestational-age infants

AIMS

To study weight, length, body composition, sleeping energy expenditure (SEE), and respiratory quotient (RQ) at birth and at 5 mo of age in both adequate-for-gestational-age (AGA) and large-for-gestational-age (LGA) subjects; to compare the changes in body weight and body composition adjusting for gender, age, SEE, RQ and several maternal factors; to investigate the contribution of initial SEE and RQ to changes in body weight and body composition.

METHODS

Sixty-nine neonates were recruited among term infants in the University Hospital of Verona, Italy. Forty-nine subjects participated until follow-up. At birth and follow-up, weight and length were measured and arm-fat area and arm-muscle area were calculated from triceps and subscapular skinfolds. SEE and RQ were measured by indirect calorimetry.

RESULTS

At birth, weight, length, arm-muscle and arm-fat areas were significantly higher in LGA subjects than in AGA subjects. Weight status, SEE and RQ at birth did not explain the relative weight change after adjusting for gestational weight, placental weight, age at follow-up and gender. Arm-fat area and weight/length ratio at birth were negatively associated with relative changes in body weight after adjusting for the above variables (p < 0.05).

CONCLUSION

Early growth from birth to 5 mo of life is significantly affected by body size and adiposity at birth. Fatter newborns had a slower growth rate than thinner newborns.

Identification of a novel human sand family protein in human fibroblasts induced by herpes simplex virus 1 binding

Studies on interaction between Herpes simplex virus 1 (HSV-1) and human fibroblasts KMB-17 have demonstrated that HSV-1 binding to the cell surface could induce a specific gene response. In this study, the HSV-1 stimulation-related gene 1 (HSRG1), a new so far unknown gene function of cellular response induced by a specific stimulation with HSV-1, was cloned from the cDNA library established from mRNA of early gene response of KMB-17 cells. The gene product consisted of 547 amino acids and had a significant homology, in six eukaryotic species. On the basis of its structure it was identified as a member of the SAND protein family. The HSRG1 protein was fused with glutathione S-transferase (GST) and expressed in Escherichia coli DHPalpha strain under the control of T7 promoter. An antibody to HSRG1 raised in mice was used to detect expression of the HSRG1 protein in KMB-17 cells stimulated by HSV-1 by an immunoprecipitation assay. It was found that the HSRG1 protein was induced in these cells by HSV-1 at high level.

[Establishment of a multiplex PCR system to detect plasmodium]

AIM

To establish a simple, rapid and practical multiplex PCR system to detect Plasmodium vivax(P. v) and Plasmodium falciparum(P. f).

METHODS

A common upper primer S1 and two species-specific lower primers of P. v and P. f, S2, S3 were designed according to the sequences of the small subunit ribosomal DNA (SSUrDNA) fragments of the two Plasmodium species. Using these three oligonucleotide primers, the two-temperature-point multiplex PCR system was established and applied to detect P. v and P. f in the stock blood samples of clinically confirmed patients.

RESULTS

DNA fragments of about 705 and 575 base pairs were successfully amplified by multiplex PCR from the genomic DNA of P. v and P. f, but no fragments were obtained from that of P. knowlesi, P. cynomolgi and blood of healthy persons. By means of restriction endonuclease digestion, the amplified fragments were confirmed to be the SSUrDNA fragments of P. v and P. f as expected. This method was successfully used in detecting parasitemia 2-10 parasite/microliter whole blood. Of 104 samples tested by this system, 81 were coincident with microscopic examination. The multiplex PCR system also found 17 samples of mixed infection, which were not detected microscopically. Another 2 samples detected as P. v by microscopic examination were verified to be P. f infection by the multiplex PCR.

CONCLUSION

The ease of operation together with high sensitivity and specificity, particularly the sensitive detection for mixed infection in a single run of amplification suggests that the multiplex PCR system might be a useful tool for malaria diagnosis.

[Alteration of blood glucose, insulin and lipid in the offsprings of patients with essential hypertension]

We prospectively investigated the serum insulin, glucose and serum lipoproteins in 40 normotensive offsprings(test group) of parents with essential hypertension compared with 35 normotensive offsprings (control group) of the normotensive families. Compared with control group, the test group was significantly elevated in fasting serum insulin levels(6.82 +/- 2 vs 4.02 +/- 1.7 microU.ml-1) (P < 0.05), fasting serum glucose(4.32 +/- 0.4 vs 3.84 +/- 0.5 mmol.L-1), serum total triglycerides(1.97 +/- 0.8 vs 1.32 +/- 0.5 mmol.L-1), total cholesterol(Tch) (5.13 +/- 1.0 vs 4.24 +/- 0.6 mmol.L-1), low density lipoprotein cholesterol (2.82 +/- 1.0 vs 2.24 +/- 0.7 mmol.L-1), very low density lipoprotein cholesterol (1.02 +/- 0.4 vs 0.66 +/- 0.27 mmol.L-1), high density lipoprotein cholesterol/Tch ratio (0.27 +/- 0.08 vs 0.33 +/- 0.07 mmol.L-1). While post-glucose load the serum insulin and glucose level after glucose load were much higher (P < 0.01) in the test group than that in controls. The findings demonstrated that young normotensive offsprings of parents with hypertension had excellent health, they had an impairment of insulin-mediated glucose disposal, hyperinsulinemia, and dyslipidemia. These findings supported that a common hereditary defect exits in familial trait for essential hypertension and disturbance of carbohydrate and lipoprotein metabolism may be detected before or at least at very early stage of the development of essential hypertension.

Expression of prostaglandin I(2) synthase, but not prostaglandin E synthase, changes in myometrium of women at term pregnancy

Prostaglandins (PGs) act as potent uterotonins at the time of labor. Prostaglandin E synthase (PGES) is responsible for the formation of PGE(2), a uterotonin. PGI(2) is synthesized by the prostaglandin I synthase enzyme (PGIS) and contributes to relaxation in the lower uterine segment. We examined the expression of membrane-bound PGES and PGIS in myometrium from pregnant women during preterm and term labor. Tissues were collected from the lower uterine segment from preterm no labor, preterm labor, term no labor, and term labor patients and used for immunohistochemistry and Western blot analysis using specific antibodies. Immunoreactive (ir-) PGES and PGIS proteins were localized to the cytoplasm of myocytes of the myometrium and vascular smooth muscle cells. Ir-PGES was also detected in vascular endothelial cells. Western blot analyses revealed a predominant protein band of 180 kDa, and a second 16-kDa band for ir-PGES and 56-kDa band for ir-PGIS. There was no significant change in ir-PGES protein (180 or 16 kDa) or mRNA levels with preterm or term labor or gestational age. There was a significant decrease in PGIS mRNA and protein with advancing gestational age. We conclude that the gestational age decrease in the inhibitory PGIS is consistent with lessening of its influence in myometrium at the time of labor. The lack of change in PGES indicates that alterations at other points along the pathway of arachidonic acid metabolism may be of greater importance in affecting local changes in PGE(2).

Microsatellites in starch-synthesizing genes in relation to starch physicochemical properties in waxy rice ( Oryza sativa L.)

Rice starch is composed of amylose and amylopectin. Amylose content, an important determinant of rice starch quality, is primarily controlled by the waxy gene, encoding granule-bound starch synthase (GBSS). The starch branching enzyme (SBE) and soluble starch synthase (SSS) play major roles in the synthesis of amylopectin. Microsatellite polymorphisms in the three genes, the wx gene encoding granule-bound starch synthase I, the SBE gene encoding starch branching enzyme I and the SSS gene encoding soluble starch synthase I, were studied for 56 accessions of waxy rice ( Oryza sativa L.). Four (CT)(n) microsatellite alleles, (CT)(16), (CT)(17), (CT)(18) and (CT)(19), at the wx locus were detected in this set of waxy rice, of which (CT)(17) was the most frequent. Three (CT)(n) microsatellite allele classes were found at the SBE locus, (CT)(8) or (CT)(10) together with an insertion sequence of CTCTCGGGCGA, and (CT)(8) alone without the insertion. There were multiple microsatellites clustered at the SSS locus. However, these alleles can also be grouped into three classes, i.e. the allele class SSS-A = (AC)(2) em leader TCC(TC)(11) em leader (TC)(5)C(ACC)(11), the allele class SSS-B = (AC)(3) em leader TCT(TC)(6) em leader (TC)(4)C(ACC)(9), and the allele class SSS-C = (AC)(3) em leader TCT(TC)(6) em leader (TC)(4)C(ACC)(8). The analyses of starch physicochemical properties among different microsatellite genotypes indicated that the waxy rice group with the (CT)(19) allele, the SBE-A allele and the SSS-B allele was quite different from other groups. Nine out of 15 accessions with a high gelatinization temperature (GT) belonged to the wx (CT)(19) group, all of them belonged to the SBE-A group and 13 of them belonged to the SSS-B group. These microsatellites might be useful in marker-assisted breeding for the improvement of rice grain quality.

[Relationship between hypotension during hemodialysis and autonomic dysfunction in diabetic hemodialysis patients]

OBJECTIVE

To observe the change of autonomic nerve function in diabetes mellitus(DM) patients who receive hemodialysis and to explore the relationship between this change and hypotension during hemodialysis.

METHODS

Twenty-five DM patients and 40 chronic glomerulonephritis(CGN) patients who received hemodialysis were checked. We tested their coefficient of variation R-R(CVR-R) in ECG, difference of systolic blood pressure between lying and standing positions, and serum parathyroid hormone(PTH); monitored the decrease of blood pressure during hemodialysis.

RESULTS

The rate(80.0%) of autonomic dysfunction(AD) in DM group is significantly higher than that(57.5%, P < 0.05) in CGN group. The rate(37.2%) of hypotension in those who had AD was significantly higher than that(18.2%, P < 0.05) in those who had normal autonomic nerve function during hemodialysis. No significant difference was found in PTH between each group.

CONCLUSION

DM patients who receive hemodialysis are often complicated with AD, which is one of the reasons that causes hypotension during hemodialysis.

The neurogenetics of mucolipidosis type IV

BACKGROUND

Mucolipidosis type IV (MLIV) is an autosomal recessive disease caused by mutations in the MCOLN1 gene that codes for mucolipin, a member of the transient receptor potential (TRP) gene family.

OBJECTIVE

To comprehensively characterize the clinical and genetic abnormalities of MLIV.

METHODS

Twenty-eight patients with MLIV, aged 2 to 25 years, were studied. Ten returned for follow-up every 1 to 2 years for up to 5 years. Standard clinical, neuroimaging, neurophysiologic, and genetic techniques were used.

RESULTS

All patients had varying degrees of corneal clouding, with progressive optic atrophy and retinal dystrophy. Twenty-three patients had severe motor and mental impairment. Motor function deteriorated in three patients and remained stable in the rest. All had a constitutive achlorhydria with elevated plasma gastrin level, and 12 had iron deficiency or anemia. Head MRI showed consistent characteristic findings of a thin corpus callosum and remained unchanged during the follow-up period. Prominent abnormalities of speech, hand usage, and swallowing were also noted. Mutations in the MCOLN1 gene were present in all patients. Correlation of the genotype with the neurologic handicap and corpus callosum dysplasia was found.

CONCLUSIONS

MLIV is both a developmental and a degenerative disorder. The presentation as a cerebral palsy-like encephalopathy may delay diagnosis.

[Study on the relationship between plasma endothelin nitric oxide concentration and renal hypertension and renal function]

OBJECTIVE

To investigate the relationship between plasma endothelin(ET), nitric oxide(NO) levels and, renal hypertension and renal function.

METHODS

The plasma concentration of ET-1 was detected by immunofluorescence assay. The plasma concentration of NO was detected by biochemistry assay.

RESULTS

1. In renal disease patients, plasma concentration ET-1 was markedly elevated, and plasma concentration of NO was decreased, compared with the healthy subjects(P < 0.01). 2. Plasma concentration of ET-1 was markedly increased and plasma concentration of NO was decreased in the patients with renal hypertension. 3. Plasma level of ET-1 was higher, and plasma level of NO was lower in the patients with renal function damage than that of those without renal function damage. 4. BP, BUN and Scr were positively correlated with plasma ET-1, but they were negatively correlated with plasma concentration of NO.

CONCLUSION

Plasma ET-1 and NO may play an important role in pathogenesis of renal hypertension; the change of their levels may be related to the progress of these renal diseases.

[Roles of sex hormones and oxygen free radical in coronary heart disease]

To examine the roles of sex hormones and oxygen free radical(OFR) in coronary heart disease (CHD), the serum estradiol(E2), testosterone(T), SOD, MDA and lipid levels were measured in 44 postmenopausal women with CHD and 22 health women. Mean levels of T and MDA were significantly higher while mean levels of SOD and E2 were significantly lower in CHD group than those in control group. On relative analysis, there was a positive correlation between E2 and SOD, while a negative correlation was observed between T and MDA in CHD group. Eighteen postmenopausal women with CHD had been receiving nilestriol replacement therapy for 12 weeks. The serum SOD and HDL-C/TC levels increased significantly, but LDL-C and MDA decreased significantly. The overall data suggest that OFR plays an important role in CHD; Low E2 levels is a risk factor of CHD in postmenopausal women; Nilestriol replacement therapy can improve the metabolism of serum lipids and inhibit lipid peroxidation, therefore, it may be of benefit to postmenopausal women with CHD.

[Investigation of the bone mineral density in hemodialysis patients for different terms]

The investigate the change of bone mineral density(BMD) in hemodialysis patients for different terms of hemodialysis, 50 patients were divided into three groups according to the duration of hemodialysis. Group I was < 5 years. Group II was 5-10 years, and Group III > 10 years. The BMD of the patients were assayed by using dual energy X-ray bone absorptiometer. Serum calcium, phosphorus, aluminium, and intact parathyroid hormone(iPTH) were detected at the same time. The mean BMD and serum iPTH were 0.624 +/- 0.180 g.cm-2 and 9.67 +/- 9.46 ng.cm-1 in Group I, 0.573 +/- 0.160 g.ml-2 and 10.16 +/- 28.05 ng.ml-1 in Group II, and 0.513 +/- 0.117 g.cm-2 and 10.75 +/- 24.94 ng.ml-1 in Group III, respectively. There was no statistical significance in BMD (P > 0.05) and iPTH(P > 0.05) among the above groups. The BMD of hemodialysis patients is not affected by different terms of hemodialysis.

Localization of nuclear factor-kappa B (NF kappa B) and inhibitory factor-kappa B (I kappa B) in human fetal membranes and decidua at term and preterm delivery

The human fetal membranes and decidua are thought to be involved in the onset of human parturition. These tissues produce and respond to various cytokines, which may be involved in preterm labour and possibly term labour. They also show increasing production of prostaglandins (PGs) with advancing gestation and labour. The expression of PGHS-2, a rate limiting enzyme in PG synthesis, is increased in the fetal membranes at labour. The gene for PGHS-2 and many of the cytokine genes (e.g. TNFalpha, IL-1, IL-6) are stimulated by the transcription factor NF kappa B. This factor is composed of two subunits, p50 and p65, which are localized in the cytoplasm bound to I kappa B. When activated I kappa B is metabolized, and p50, p65 translocate to the nucleus to activate various genes. The purpose of the present study was to examine the tissue and cellular distribution of p65 and I kappa B in the human fetal membranes and decidua throughout gestation. Term tissues were obtained prior to labour by elective caesarean section (n=10) or following vaginal delivery (n=10) and 10 preterm tissues were obtained following labour prior to 37 weeks gestation. None of the tissues had any evidence of infection. The immunoreactive NF kappa B and I kappa B were localized in the tissues. p65 protein was found in the nucleus and cytoplasm of cells in the amnion, chorion laeve and decidua. In the amnion and chorion laeve, no changes occurred in subcellular localization with advancing gestation or term labour. However, in the decidua, there was a marked increase in the nuclear localization of i.r. p 65 in tissues obtained at term when compared with tissues delivered preterm. In the case of I kappa B, it was localized to the cytoplasm of cells in all tissues and there was an increase i.r. I kappa B in decidua at term compared to preterm but no change occurred in the amnion or chorion. The increase in nuclear localization of p65 in the decidua that occurs with advancing gestation, highlights the potential importance of this factor in the regulation of parturition related genes in this tissue.

Sleeping metabolic rate in relation to body mass index and body composition

OBJECTIVES

To determine whether patterns of sleeping metabolic rate (SMR) are altered in obesity. Specifically to determine the relationship between changes in SMR and body weight, body mass index (BMI, kg/m(2)), and fat-free mass (FFM); and to compare resting metabolic rate (RMR) with SMR during different periods of sleep.

SUBJECTS

Eighteen healthy, pre-menopausal, obese (BMI >30, n=9) and non-obese (BMI <30, n=9), female subjects (six Caucasians and 12 African-Americans), with an average age of 36 y (range 22-45).

MEASUREMENTS

Total energy expenditure (TEE or 24 h EE), metabolic rate (MR), SMR (minimum, average and maximum) and resting metabolic rate (RMR) or resting energy expenditure (REE) measured by human respiratory chamber, and external mechanical work measured by a force platform within the respiratory chamber. Physical activity index (PAL) was derived as TEE/REE. Body composition was determined by dual-energy X-ray absorptiometry (DXA).

RESULTS

SMR decreased continuously during sleep and reached its lowest point just before the subject was awakened in the morning by the research staff. Although averages for RMR and SMR were similar, RMR was lower than SMR at the beginning of the sleeping period and higher than SMR in the morning hours. The rate of decrease in SMR was faster with increasing body weight (-0.829, P<0.0001), BMI (correlation factor -0.896, P<0.0001) and FFM (-0.798, P=0.001). The relationship between the slope of SMR decrease and BMI (y=-5 x 10(-6)x(2)+0.0002x-0.0028) is highly significant, with a P-value of <0.0001 and r(2) value of 0.9622.

CONCLUSIONS

The rate of decline in metabolic rate during sleep is directly related to body weight, BMI and FFM. Average SMR tends to be lower than RMR in obese subjects and higher than RMR in non-obese subjects.

Analysis of the genetic behavior of some starch properties in indica rice ( Oryza sativa L.): thermal properties, gel texture, swelling volume

Starch comprises about 90% of milled rice, so that the eating and cooking quality of rice is mainly affected by the starch properties. In the present paper, we analyzed the genetical behavior of gelatinization temperature tested by differential scanning calorimetry (DSC), gel texture, and the swelling volume (SV) of indica rice with an incomplete cross of 4x8 parents. A genetic model which can dissect the effects of triploid seed, the cytoplasm, and the maternal plant on the endosperm traits was used. The results indicated that peak temperature (T(p)), conclusion temperature (T(c)) and enthalpy (DeltaH) were controlled by three types of genetic effects: seed direct (endosperm) effects, cytoplasmic effects and maternal effects. No cytoplasmic effects for the onset temperature (T(o)), hardness and SV, and no maternal effects for cohesiveness were found. The additive variances ( V (A)+ V (Am)) were larger than the dominance variances ( V (D)+ V (Dm)) for all the traits except for T(c), which suggested that selection could be applied for the starch properties in early generations. The total narrow-sense heritability for each parameter was over 60%, indicating that selection advances were predictable in the early generations for these traits.

[Detection of SYT-SSX fusion gene in paraffin-embedded tissues and its clinicopathologic significance for synovial sarcoma]

OBJECTIVE

To investigate the feasibility of detecting SYT-SSX fusion gene in paraffin-embedded tissues and its diagnostic significance for synovial sarcoma (SS).

METHODS

Formalin-fixed, paraffin-embedded samples of 38 cases of SS and 40 cases of control tumors (including spindle cell sarcoma and metastatic adenocarcinoma) were retrived from archival materials. SYT-SSX fusion transcripts were detected in all samples by RT-PCR. House-keeping gene Porphobilinogen Deaminase (PBGD) was used to detect the quality of mRNA.

RESULTS

PBGD mRNA was detected in 64 of the 78 tumor cases (82.1%). SYT-SSX fusion transcripts was detected in 33 of the 38 synovial sarcoma specimens. No SYT-SSX mRNA expression was found in control tumors. SYT-SSX mRNA expression rate reached 89.2% (33/37) in synovial sarcomas after exclusion of 1 case which was negative for both SYT-SSX and PBGD. In 33 SYT-SSX positive synovial sarcomas, 22 had SYT-SSX1 and 6 had SYT-SSX2 fusion transcripts. In 5 cases, the fusion type could not be distinguished. There was an association between SYT-SSX fusion type and histologic subtype. All 10 biphasic synovial sarcoma cases had the SYT-SSX1 fusion, whereas 12 of 18 monophasic synovial sarcoma had the SYT-SSX1 and 6 had the SYT-SSX2 fusion gene (P < 0.05).

CONCLUSIONS

(1) Detection of SYT-SSX fusion gene in paraffin-embedded tissues was found to be a sensitive and specific method for the diagnosis and differential diagnosis of synovial sarcoma. (2) There was an association between SYT-SSX fusion type and histologic subtype.SYT-SSX2 fusion transcript could only be found in monophasic synovial sarcomas.