Lack of association between COPD and transforming growth factor-beta1 (TGFB1) genetic polymorphisms in Koreans

OBJECTIVE

Many genetic variations have been suggested as genetic risk factors for the development of chronic obstructive pulmonary disease (COPD), including single nucleotide polymorphisms in the transforming growth factor-beta1 (TGFB1) gene. We attempted to elucidate the association between TGFB1 genetic polymorphisms and COPD among Koreans.

DESIGN

The genotypes of 102 male patients with COPD and 159 volunteers with similar distributions of age, sex and smoking intensity, as well as normal pulmonary function, were determined for three previously associated TGFB1 single nucleotide polymorphisms (SNPs), -10807G/A (rs2241712) and -509T/C (rs1800469), located in or near the promoter, and 29T/C (rs1982073), located in exon 1 of the TGFB1 gene.

RESULTS

No significant associations between COPD and the three TGFB1 SNPs could be identified. In addition, the haplotypes composed of three TGFB1 SNPs were not associated with the presence of COPD.

CONCLUSION

These results differ from previous reports involving Caucasians, and might reflect racial differences in the pathogenesis of COPD.

The association between microsatellite polymorphisms in intron II of the human Toll-like receptor 2 gene and tuberculosis among Koreans

The observation that Toll-like receptor (TLR)2-deficient mice are highly susceptible to mycobacteria suggests that mutations altering TLR2 expression may impair host response to Mycobacterium tuberculosis. We evaluated the association between guanine-thymine (GT) repeat polymorphism in intron II of the TLR2 gene and the presence of tuberculosis (TB) in Koreans. The numbers of GT repeats were determined by PCR and gene scans for 176 TB patients and 196 controls. The recombinant TLR2 promoter/exonI/exonII/intronII/luciferase constructs including three representative repeats: (GT)13, (GT)20, and (GT)24 were transfected into K562 cells, and luciferase activities were estimated and compared. The expression of TLR2 on CD14+ peripheral blood mononuclear cells (PBMC) from healthy volunteers were measured with flow cytometry. Genotypes with shorter GT repeats were more common among TB patients (49.4 vs 37.7%, P=0.02). This observation was confirmed among 82 other TB patients as a validation cohort. Shorter GT repeats were associated with weaker promoter activities and lower TLR2 expression on CD14+ PBMCs. In conclusion, the development of TB disease in Koreans was associated with shorter GT repeats in intron II of the TLR2 gene. This association is correlated with lower expression of TLR2 through weaker promoter activity for genes with shorter GT repeats.

Activation of NF-κB by HDAC inhibitor apicidin through Sp1-dependent de novo protein synthesis: its implication for resistance to apoptosis

Histone deacetylase (HDAC) inhibitors are promising anti-cancer drugs, but these exert differential responses depending on the cell types. Here, we demonstrate a new mechanism for activation of nuclear factor-kappaB (NF-kappaB) by HDAC inhibitor apicidin and the role of NF-kappaB signaling pathway for mediating differential cellular responses, especially, apoptosis. Treatment of HeLa cells with apicidin increases transcriptional activity of NF-kappaB and its target gene IL-8 and cIAP-1 induction, which involves the activation of IKK-IkappaBalpha signaling pathway through Sp1-dependent de novo protein synthesis. In parallel, apicidin treatment leads to histone hyperacetylation in the IL-8 promoter region independent of NF-kappaB signaling pathway, which is not sufficient for full transcription of IL-8 gene. This NF-kappaB activation contributes to resistance of HeLa cells to apoptotic potential of apicidin. Collectively, our results suggest that activation of NF-kappaB signaling cascade functions as a critical modulator to determine cell fate on apoptosis in response to HDAC inhibitors.

Prevalence of erectile dysfunction in Korean men with Type 2 diabetes mellitus

AIMS

We investigated the prevalence and risk factors for developing erectile dysfunction (ED) in 1312 Korean men with diabetes in a multicentre study.

METHODS

We used the modified International Index for Erectile Function-5 criteria to identify mild, moderate and complete ED. A standardized face-to-face questionnaire was used by trained interviewers, and validated against telephone interviews. We recorded the duration of diabetes, level of glycaemic control, vital signs, complications, exercise and alcohol and smoking habits, and diabetes treatments used. Results The mean age and median duration of diabetes were 53.8 +/- 6.65 and 6 years (range 1-43), respectively. The mean HbA(1c) and fasting glucose levels were 7.9 +/- 1.65% and 8.6 +/- 2.82 mmol/l, respectively. The overall prevalences of mild, moderate, complete ED and all ED (mild-to-complete) were 20.1, 19.5, 25.8 and 65.4%, respectively. ED was more common with age, reaching 79.3% in men aged > 60 years. Subjects aged > 60 years and with a duration of diabetes > 10 years were at greatest risk for all ED (OR = 10.4, 95% CI 5.8-18.5, P < 0.001) and complete ED (OR = 13.2, 95% CI 7.3-23.9, P < 0.001) when compared with the reference group (age 40-50 years with duration < 6 years). Age, duration of diabetes, HbA(1c), insulin use, neuropathy and macrovascular complications were positively associated with ED, but alcohol consumption and exercise habits were negatively associated.

CONCLUSIONS

The prevalence of complete ED was approximately six times higher than in the general population.

Evaluation of concordance of Gleason score between prostatectomy and biopsies that show more than two different Gleason scores in positive cores

OBJECTIVES

To evaluate variables that may predict the Gleason score of radical prostatectomy specimens in patients with more than two different Gleason scores in the positive cores of their biopsy specimens.

METHODS

We reviewed the pathologic data of 98 patients who had more than two different Gleason scores in 12-site biopsy specimens. We assessed the following biopsy parameters: the greatest Gleason score on the biopsy specimen, the Gleason score of the greatest tumor percentage in the core, the Gleason score of the largest linear cancer length, and the greatest tumor ratio score (Gleason score of the greatest total tumor length of the same Gleason score/total core length of the same Gleason score). We also assessed the concordance in Gleason scores between biopsy specimens and prostatectomy specimens.

RESULTS

The greatest tumor ratio score was associated with the greatest (67%) concordance rate. The concordance of the greatest Gleason score on biopsy specimens was only 49%. When stratified into categories of well-differentiated (Gleason score 6 or less), moderate (Gleason score 7), and poorly differentiated (Gleason score 8 or more), the grade concordance rate of the greatest tumor ratio score was 73%. The grade concordance rate of the Gleason scores of the greatest tumor percentage in the core, Gleason score core with maximal tumor length, and the greatest Gleason score was 64%, 62%, and 57%, respectively.

CONCLUSIONS

If biopsy specimen results in more than two different Gleason scores in the positive cores, the greatest tumor ratio score may be the most useful variable with regard to the prediction of the final Gleason score in the radical prostatectomy specimen.

Quantitation of niflumic acid in human plasma by high-performance liquid chromatography with ultraviolet absorbance detection and its application to a bioequivalence study of talniflumate tablets

A rapid and simple HPLC method with UV detection (288 nm) was developed and validated for quantitation of niflumic acid in human plasma, the active metabolite of talniflumate. After precipitation with 100% methanol containing the internal standard, indomethacin, the analysis of the niflumic acid level in the plasma samples was carried out using a reverse phase C18 CAPCELL PAK (5 microm, 4.6 mm x 250 mm) column. The chromatographic separation was accomplished with an isocratic mobile phase consisting of a mixture of 0.1M sodium acetate in water and acetonitrile (37:63, v/v), adjusted to pH 6.4. This HPLC method was validated by examining its precision and accuracy for inter- and intra-day runs in a linear concentration range of 0.02-5.00 microg/mL. Stability of niflumic acid in plasma was excellent, with no evidence of degradation during sample processing (autosampler) and 30 days storage in a freezer. This validated method was successfully applied to the bioequivalence study of talniflunate in healthy volunteers.

Cortical excitability during prolonged antiepileptic drug treatment and drug withdrawal

OBJECTIVE

Previous reports characterized the effects of administration of single oral doses of antiepileptic drugs (AED) on cortical excitability. However, AED effects on cortical excitability, and their relationship to plasma blood levels, during chronic drug administration at therapeutic doses are not known. The objective of the study was to determine whether plasma blood levels during chronic administration at therapeutic doses would accurately predict changes in corticomotor excitability.

METHODS

We used transcranial magnetic stimulation (TMS) to measure cortical excitability during 5 weeks administration of carbamazepine (CBZ) and lamotrigine (LTG), and subsequent AED withdrawal in 20 healthy volunteers. Data were analyzed using ANOVA(RM) and regression analysis.

RESULTS

Resting motor thresholds (r-MT) increased with increasing total and free CBZ and LTG levels during drug administration, but not drug withdrawal. After acute AED withdrawal, r-MT elevation persisted in most individuals with CBZ despite undetectable plasma levels, compared to a rapid normalization with LTG. In contrast, acute drug withdrawal resulted in a transient decrease in r-MT in 3/10 individuals with CBZ and 2/10 with LTG.

CONCLUSIONS

Plasma levels provide information on motor cortical function during active treatment phases but not during AED withdrawal.

SIGNIFICANCE

The transient decrease in r-MT associated with acute AED withdrawal could represent a physiological substrate contributing to AED withdrawal seizures.

Functional expression of a recombinant copper/zinc superoxide dismutase of filarial nematode, Brugia malayi

A gene encoding a copper/zinc superoxide dismutase (Cu/ Zn-SOD) of a filarial nematode, Brugia malayi, has been isolated and the biochemical properties of a functionally expressed recombinant enzyme were investigated. The cloned complementary DNA contained a single open reading frame of 477 bp encoding 158 amino acids (aa), which conserved metal-binding residues as well as residues specific for Cu/Zn-SODs. Comparison of the deduced aa sequence of the enzyme with that of other helminthes species, including filarial worms, exhibited high degree of similarities (49-98%). Recombinant enzyme of 32 kDa had an isoelectric point of 6.6 and was shown to consist of 2 subunits linked by interchain disulfide bonds. Enzyme activity of the recombinant protein was inhibited by potassium cyanide and hydrogen peroxide but not by sodium azide. It showed a wide range of pH optima, i.e., 7.0-11.0 and was highly resistant to heat inactivation.

Postoperative adjuvant chemotherapy for stage I non-small cell lung cancer

OBJECTIVE

Surgery constitutes the mainstay of treatment in stage I non-small cell lung cancer (NSCLC). However, a significant fraction of patients after surgical resection die mainly due to systemic relapse. Nonetheless, the best adjuvant treatment to improve survival and decrease relapse rate remains as an ever controversial issue. Therefore, we conducted a randomized trial to determine whether postoperative adjuvant chemotherapy is beneficial in prolonging survival and decreasing recurrence in patients with completely resected stage I NSCLC.

METHODS

It was designed as a randomized, prospective two-armed study with surgery only (control group, 59 patients) versus surgery plus adjuvant MVP (mitomycin C, vinblastin and cisplatin) chemotherapy (study group, 59 patients).

RESULTS

Data for all the patients were complete. Twenty-four patients in the control group and nine patients in the study group experienced tumor recurrence during the follow-up. Neither histological type nor surgical extent correlated with recurrence. However, the addition of adjuvant MVP chemotherapy could decrease the rate of recurrence and the incidence of cancer-related death after surgery in the patients of stage I NSCLC (P<0.05). We followed up at least 5 years, and the duration of mean follow-up was 7.3 years. The rates of the loco-regional and distant metastases were 3.4 and 40.7% in the control group, and 3.4 and 11.9% in the study group, respectively. The 5- and 10-year survival rates were 74.6 and 56.3% in the control group, and 81.4 and 65.0% in the study group, respectively (P=0.19, log-rank test). The 5- and 10-year disease-free survival rates were 64.8 and 54.8% in the control group, and 88.8 and 76.8% in the study group, respectively (P=0.002, log-rank test).

CONCLUSIONS

Our results suggest that the addition of adjuvant MVP chemotherapy may reduce the incidence of distant metastasis and prolong the disease-free survival of the patients with stage I NSCLC after surgery.

Molecular cloning and characterization of the copper/zinc and manganese superoxide dismutase genes from the human parasiteClonorchis sinensis

A copper/zinc superoxide dismutase (Cu/ZnSOD) gene and a manganese superoxide dismutase (MnSOD) gene of the human parasiteClonorchis sinensishave been cloned and their gene products functionally characterized. GenesCu/ZnSODandMnSODencode proteins of 16 kDa and 25·4 kDa, respectively. The deduced amino acid sequences of the two genes contained highly conserved residues required for activity and secondary structure formation of Cu/ZnSOD and MnSOD, respectively, and show up to 73·7% and 75·4% identities with their counterparts in other animals. The genomic DNA sequence analysis of Cu/ZnSOD gene revealed this as an intronless gene. Inhibitor studies with purified recombinant Cu/ZnSOD and MnSOD, both of which were functionally expressed inEscherichia coli, confirmed that they are copper/zinc and manganese-containing SOD, respectively. Immunoblots showed that bothC. sinensisCu/ZnSOD and MnSOD should be antigenic for humans, and both, especially theC. sinensisMnSOD, exhibit extensive cross-reactions with sera of patients infected by other trematodes or cestodes. RT-PCR and SOD activity staining of parasite lysates indicate that there are no significant differences in mRNA level or SOD activity for both species of SOD, indicating cytosolic Cu/ZnSOD and MnSOD might play a comparatively important role in theC. sinensisantioxidant system.

Cloning and characterization of GITR ligand

The gene encoding the natural ligand of murine glucocorticoid-induced tumor necrosis factor receptor (GITR) was cloned and characterized. The putative GITR ligand (GITRL) is composed of 173 amino acids with features resembling those of type II membrane proteins and is 51% identical to the human activation-inducible TNF receptor (AITR) ligand, TL6. Expression of the GITRL is restricted to immature and mature splenic dendritic cells. GITRL binds GITR expressed on HEK 293 cells and triggers NF-kappaB activation. Functional studies reveal that soluble CD8-GITRL prevents CD4+CD25+ regulatory T-cell-mediated suppressive activities.

Enhanced secretion of Bacillus stearothermophilus L1 lipase in Saccharomyces cerevisiae by translational fusion to cellulose-binding domain

The secretion of Bacillus stearothermophilus L1 lipase in Saccharomyces cerevisiae was investigated by employing a fusion partner, a cellulose-binding domain (CBD) from Trichoderma harzianum endoglucanase II (THEG). The CBD was connected to the N-terminal of L1 lipase through an endogenous linker peptide from THEG. The expression cassette for the fusion protein in S. cerevisiae was constructed using the alpha-amylase signal peptide and the galactose-inducible GAL10 promoter. Secretion of CBD-linker-L1 lipase by this fusion construct was dramatically 7-fold enhanced, compared with that of the mature L1 lipase without CBD-fusion. The fusion protein was secreted into the culture medium, reaching levels of approximately 1.3 g/l in high-cell-density fed-batch cultures. Insertion of a KEX2 cleavage site into the junction between CBD-linker and L1 lipase resulted in the same level of enhanced secretion, indicating that the CBD-linker fusion probably plays a critical role in secretion from endoplasmic reticulum to Golgi apparatus. Therefore, the CBD from THEG can be used both as an affinity tag and as a secretion enhancer for the secretory production of heterologous proteins in S. cerevisiae, since in vivo breakage at the linker was almost negligible.

Steady-state solutions of hydrodynamic traffic models

We investigate steady-state solutions of hydrodynamic traffic models in the absence of any intrinsic inhomogeneity on roads such as on-ramps. It is shown that typical hydrodynamic models possess seven different types of inhomogeneous steady-state solutions. The seven solutions include those that have been reported previously only for microscopic models. The characteristic properties of wide jam such as moving velocity of its spatiotemporal pattern and/or out-flux from wide jam are shown to be uniquely determined and thus independent of initial conditions of dynamic evolution. Topological considerations suggest that all of the solutions should be common to a wide class of traffic models. The results are discussed in connection with the universality conjecture for traffic models. Also the prevalence of the limit-cycle solution in a recent study of a microscopic model is explained in this approach.

Nitrogen removal characteristics analyzed with gas and microbial community in thermophilic aerobic digestion for piggery waste treatment

In order to characterize the nitrogen conversion characteristics in a thermophilic aerobic digestion (TAD) system, a laboratory study has been conducted with the analysis of effluent gas and microbial community in the sludge samples. The lab TAD system was operated with HRT of 3 days and 60 degrees C. Based on the nitrogen mass balance, it has been found that about 2/3 of the daily load of nitrogen was converted to the gaseous form of nitrogen whereas cellular transformation and unmetabolized nitrogen accounted for about 1/3. Among the gaseous nitrogen transformation, significant amount of influent nitrogen had been converted to N2 gas (29% of influent N) and N2O (9% of influent N). Ammonia conversion was only 28% of influent N. The detection of N2O gas is a clear indication of the biological nitrogen reduction process in the thermophilic aerobic digester. No conclusive evidence for the existence of aerobic deammonification has been found. The microbial community analysis showed that thermophilic bacteria such as Bacillus thermocloacae, Bacillus sp. and Clostridial groups dominated in this TAD reactor. The diverse microbial community in TAD sludge may play an important role in removing both strong organics and nitrogen from piggery waste.

Pax-7 Immunoreactivity in the Post-natal Chicken Central Nervous System

In this immunocytochemical study on the constitutive expression of Pax-7 protein in the postnatal chicken brain, Pax-7 showed region and cell type specific expression. In the optic tectum, only cells in grey matter showed positive immunoreactivities (IRs), whereas those in the white matters did not show any IRs. In thalamic nuclei and several pontine nuclei, we also localized Pax-7 positive IRs. On the contrary, in the cerebellum, Pax-7 was mainly localized within the Bergmann glia, whereas Purkinje cells did not show any IRs. In double immunolabelling studies, most of the Pax-7 IRs did not originate from neuroglial cells such as oligodendrocytes, microglia or astrocytes, but from neurons, with the exception of Bergmann glia in the cerebellum. The presence of Pax-7 IRs in the adult chicken brain could suggest that Pax-7 might play a role in maintaining normal physiological function in some postnatal chicken brain cells.

The microbial community analysis of a 5-stage BNR process with step feed system

The microbial communities of 5-stage BNR activated sludge samples were analyzed using fluorescence in-situ hybridization (FISH) and 16S rDNA characterization. The total cell numbers of each reactor were from 2.36 x 10(9) cells/ml to 2.83 x 10(9) cells/ml. From 56.5% to 62.0% of total DAPI cell counts were hybridized to the most bacterial specific probe EUB 338. Among them, beta-proteobacteria were most dominant in each tank. The number of phosphate accumulating organisms (PAOs) was almost 50% of the total cell number in anoxic-1 tank, and these results indicate that this process has a high content of denitrifying phosphorus accumulating organisms (dPAOs). In contrast with FISH, 16S rDNA analysis showed that dominant groups were the Cytophaga-Flavobacterium group and high G+C% gram-positive bacteria, which were determined as PAOs in anoxic-1 tank. The beta subclass Proteobacteria did not accumulate a large amount of polyphosphate. The overall results indicate that high G+C% gram-positive bacteria and the Cytophaga-Flavobacterium group might play a key role as dPAOs in this process.

Novel E2F decoy oligodeoxynucleotides inhibit in vitro vascular smooth muscle cell proliferation and in vivo neointimal hyperplasia

The transcription factor, E2F, plays a critical role in the trans-activation of several genes involved in cell cycle regulation. Previous studies showed that the transfection of cis element double-stranded decoy oligodeoxynucleotides (ODNs) corresponding to E2F binding sites inhibited the proliferation of vascular smooth muscle cells (VSMCs) and neointimal hyperplasia in injured vessels. We have developed a novel E2F decoy ODN with a circular dumbbell structure (CD-E2F) and compared its effects with those of the conventional phosphorothioated E2F decoy (PS-E2F) ODN. CD-E2F ODN was more stable than PS-E2F ODN, largely preserving its structural integrity after incubation in the presence of nucleases and sera. Moreover, CD-E2F ODN inhibited high glucose- and serum-induced transcriptional expression of cell cycle regulatory genes more strongly than PS-E2F ODN. Transfection of CD-E2F ODN resulted in more effective inhibition of VSMC proliferation in vitro and neointimal formation in vivo, compared with PS-E2F ODN. An approximately 40-50% lower dose of CD-E2F ODN than PS-E2F ODN was sufficient to attain similar effects. In conclusion, our results indicate that CD-E2F ODN may be a valuable tool in gene therapy protocols for inhibiting VSMC proliferation and studying transcriptional regulation.

Measurement of day and night neutrino energy spectra at SNO and constraints on neutrino mixing parameters

The Sudbury Neutrino Observatory (SNO) has measured day and night solar neutrino energy spectra and rates. For charged current events, assuming an undistorted 8B spectrum, the night minus day rate is 14.0%+/-6.3%(+1.5%)(-1.4%) of the average rate. If the total flux of active neutrinos is additionally constrained to have no asymmetry, the nu(e) asymmetry is found to be 7.0%+/-4.9%(+1.3%)(-1.2%). A global solar neutrino analysis in terms of matter-enhanced oscillations of two active flavors strongly favors the large mixing angle solution.

Direct evidence for neutrino flavor transformation from neutral-current interactions in the Sudbury Neutrino Observatory

Observations of neutral-current nu interactions on deuterium in the Sudbury Neutrino Observatory are reported. Using the neutral current (NC), elastic scattering, and charged current reactions and assuming the standard 8B shape, the nu(e) component of the 8B solar flux is phis(e) = 1.76(+0.05)(-0.05)(stat)(+0.09)(-0.09)(syst) x 10(6) cm(-2) s(-1) for a kinetic energy threshold of 5 MeV. The non-nu(e) component is phi(mu)(tau) = 3.41(+0.45)(-0.45)(stat)(+0.48)(-0.45)(syst) x 10(6) cm(-2) s(-1), 5.3sigma greater than zero, providing strong evidence for solar nu(e) flavor transformation. The total flux measured with the NC reaction is phi(NC) = 5.09(+0.44)(-0.43)(stat)(+0.46)(-0.43)(syst) x 10(6) cm(-2) s(-1), consistent with solar models.

Genistein prevents nuclear factor-kappa B activation and acute lung injury induced by lipopolysaccharide

Protein tyrosine kinase (PTK) inhibitors have been proposed to reduce lung injury and lethal toxicity. The mechanisms responsible for the effects of PTK inhibitors remain obscure. The purpose of the present study was to examine whether genistein, a specific inhibitor of PTK, inhibits nuclear factor-kappa B (NF-kappaB) activation during acute lung injury induced by lipopolysaccharide (LPS) and, if so, to enumerate the effects of inhibition of NF-kappaB activation on LPS-induced proinflammatory gene products, such as cytokine-inducible neutrophil chemoattractant (CINC) and matrix metalloproteinase-9 (MMP-9), as well as neutrophil influx into the lungs. Intratracheal treatment of rats with LPS (6 mg/kg) resulted in increases in total protein and lactate dehydrogenase activity in bronchoalveolar lavage fluid and activated DNA-binding activity of NF-kappaB in alveolar macrophages and lung tissue. A 2-h pretreatment with genistein (50 mg/kg, intraperitoneally) inhibited the LPS-induced changes in lung injury parameters and the induction of NF-kappaB activation. Furthermore, these inhibitory effects of genistein correlated with a depression of LPS-induced protein tyrosine phosphorylation (approximately molecular masses of 46, 48, and 54 kD) and phosphorylation of Jun N-terminal kinase (JNK) in lung tissue. Genistein also substantially reduced the LPS-induced CINC production and MMP-9 activity and suppressed neutrophil recruitment. These results suggest that genistein attenuates LPS-induced acute lung responses through inhibition of NF-kappaB activation. In addition, NF-kappaB activation appears to be an important mechanism mediating LPS-induced CINC production and MMP-9 activity and resulting neutrophil recruitment associated with acute lung inflammation and injury.

Structure-reactivity relationships in the pyridinolysis of N-methyl-N-arylcarbamoyl chlorides in dimethyl sulfoxide

Nucleophilic substitution reactions of N-methyl-N-arylcarbamoyl chlorides (YC(6)H(4)N(CH(3))COCl) with pyridines (XC(5)H(4)N) have been investigated in dimethyl sulfoxide at 45.0 degrees C. A striking trend in the selectivity parameters is that they are constant within experimental errors, rho(X) = -2.25 +/- 0.03, beta(X) = 0.42 +/- 0.01, and rho(Y) = 1.10 +/- 0.06, with changing reactivities of the electrophiles (deltasigma(Y)) and nucleophiles (deltasigma(X)), respectively, and this leads to a vanishingly small cross-interaction constant, rho(XY) approximately equals beta(XY) approximately equals 0. The rate data can be expressed in the Ritchie N(+) type equation. Based on this and other results, the mechanism of nucleophile (pyridine) addition to the resonance- stabilized carbocation is proposed. It has been shown from the definition of beta(XY) (and rho(XY)) together with the Marcus equation that the high intrinsic barrier, DeltaG(0), in the intrinsic-barrier controlled reaction series is a prerequisite for such reactions in which the cross-interaction vanishes and the N(+) relationship holds.