Hypoglycemia in small for gestational age babies

The main objectives of the study were to find the incidence and risk factors associated with development of hypoglycemia in small for gestational age (SGA) babies, to compare haemoglucotest strips (Boehringer Mannheim) with the standard laboratory method (glucose-hexokinase) for estimation of blood glucose, and to measure the insulin and cortisol responses of SGA babies. This was a prospective longitudinal study. The sample included SGA babies and over a period of six months, 127 consecutively born small for gestational age babies were investigated prospectively for development of hypoglycemia in first 48 hrs of life. Plasma samples were taken during episodes of hypoglycemia for insulin and cortisol estimation and compared with non-hypoglycemic controls. The overall incidence of hypoglycemia was 25.2% in SGA babies and 98% of the episodes occurred within first 24 hrs. Compared to non-hypoglycemics, mothers of hypoglycemic babies had higher incidence of receiving i.v. fluids (5% dextrose) during labour. The hypoglycemic babies were more likely to be sick and oral feeds had been initiated by one hour of life in only 37% of them compared to 63% of non-hypoglycemic babies. Plasma insulin/glucose ratio was significantly higher in hypoglycemic than non-hypoglycemic babies, whereas the cortisol levels were similar. Small for gestational age babies are highly prone to develop hypoglycemia in first 24 hrs of life.

Magnetization transfer ratio in new MS lesions before and during therapy with IFNbeta-1a

OBJECTIVE

The authors examined the effect of 6.0 MIU interferon beta-1a (IFNbeta-1a) administered IM each week on the evolution of monthly magnetization transfer ratio (MTR) within new gadolinium-enhancing (Gd+) lesions in patients with very early relapsing-remitting (RR) MS.

BACKGROUND

IFNbeta is an effective disease-modifying treatment for patients with RRMS. Among other effects, it has been shown to decrease the number of new Gd+ and T2-weighted lesions. MTR is a putative marker for irreversible tissue damage and evolution of MTR within a lesion may reflect recovery of tissue damage. It is not known whether IFNbeta-1a affects the recovery phase of lesions.

METHODS

Eight untreated patients with RRMS who completed up to 14 monthly brain MRI sessions elected to initiate treatment with IFNbeta-1a. Four out of eight patients developed new Gd+ lesions during treatment. MTR of lesions at the time of appearance and subsequent rate of change of monthly MTR were compared before and after treatment (stratified Mann-Whitney test).

RESULTS

The difference between MTR at appearance of 47 new Gd+ lesions before treatment versus 23 new Gd+ lesions during treatment was not significant. Twenty-two of 47 new Gd+ lesions before treatment and 11 of 23 new Gd+ lesions after treatment were monitored for up to 6 months. After appearance of new Gd+ lesions, the rate of increase in MTR was faster during therapy (p = 0.037).

CONCLUSION

MTR abnormalities within new Gd+ lesions evolve at a faster rate during treatment with IFNbeta-1a than before initiating therapy. This is consistent with the hypothesis that IFNbeta-1a promotes resolution of new Gd+ lesions.

Studies on codon usage in Entamoeba histolytica

Codon usage bias of Entamoeba histolytica, a protozoan parasite, was investigated using the available DNA sequence data. Entamoeba histolytica having AT rich genome, is expected to have A and/or T at the third position of codons. Overall codon usage data analysis indicates that A and/or T ending codons are strongly biased in the coding region of this organism. However, multivariate statistical analysis suggests that there is a single major trend in codon usage variation among the genes. The genes which are supposed to be highly expressed are clustered at one end, while the majority of the putatively lowly expressed genes are clustered at the other end. The codon usage pattern is distinctly different in these two sets of genes. C ending codons are significantly higher in the putatively highly expressed genes suggesting that C ending codons are translationally optimal in this organism. In the putatively lowly expressed genes A and/or T ending codons are predominant, which suggests that compositional constraints are playing the major role in shaping codon usage variation among the lowly expressed genes. These results suggest that both mutational bias and translational selection are operational in the codon usage variation in this organism.

The need for clinical evaluation and semen analysis of infertile men

OBJECTIVE

Although many men in Third World countries are reluctant to participate in an infertility work-up, we collected data from a group of husbands of females attending our infertility clinic. We intend to present these results as motivation for other men to realize the importance of an evaluation when they are involved in a barren marriage.

STUDY METHODS

A detailed history was taken, and physical and urogenital examination was carried out on 400 male partners of women attending the infertility clinic of PGIMER Chandigarh. Semen analysis was interpreted as normal or abnormal according to the WHO manual.

RESULTS

Age of the male partners of 400 infertile couples and their duration of infertility correlated with the pregnancy rate. Fifty percent of the men with a past history of infection, medical or surgical problems had abnormal semen analysis. The presence of urogenital abnormalities had a significant correlation with low sperm count and low motility. Social problems related to alcohol and smoking produced low pregnancy rates.

CONCLUSION

A detailed history, examination and work-up of male partners of infertility couples is as important as in the female partner. Counseling and treatment may improve pregnancy rates.

Membrane surface of Mycobacterium microti-infected macrophages antigenically differs from that of uninfected macrophages

Identification of the antigenic changes in mycobacteria-infected macrophage may be important in understanding the mechanisms responsible for the intracellular survival of the bacteria. In the present study, Mycobacterium microti-infected macrophages were utilized to investigate the possibility of differentiating the infected cells from normal cells, based on the antigenic changes occurring in the membranes. Antisera were generated against bacterial extract, heat-killed bacteria and crude preparation of M. microti-infected homologous macrophage membrane. The reactivity of these antisera, towards in vitro infected macrophages, was compared by flow cytometry. Unlike anti-bacterial extract antiserum or anti-heat-killed bacterial antiserum, anti-infected macrophage membrane antiserum reacted with infected macrophage surface. This reactivity increased with the increase in post-infection time. However, it was not observed with uninfected macrophages, PMA- or lipopolysaccharide-activated macrophages and those harboring Mycobacterium tuberculosis H37Ra, heat-killed M. microti and Leishmania donovani. Interestingly, anti-infected macrophage membrane antiserum identified a 63-kDa antigen in M. microti-infected macrophage membranes which was not present in the membranes of normal macrophages, activated macrophages and of those infected with M. tuberculosis H37Ra, heat-killed M. microti and L. donovani. Thus, membranes of M. microti-infected macrophages differ antigenically from those of the normal macrophages and infected homologous macrophage membrane antiserum provides a useful tool in studying such changes.

RegA, iron, and growth phase regulate expression of the Pseudomonas aeruginosa tol-oprL gene cluster

The tol-oprL region in Pseudomonas aeruginosa appears to be involved in pyocin uptake and required for cell viability. The complete nucleotide sequences of the tolQRA and oprL genes as well as the incomplete sequences of tolB and orf2 have been previously reported. In addition, the sequence of a P. aeruginosa iron-regulated gene (pig6) has been described and found to share homology with an open reading frame located upstream of the Escherichia coli tolQRA genes (U. A. Ochsner and M. L. Vasil, Proc. Natl. Acad. Sci. USA 93:4409-4414, 1996). In this study, we cloned the remainder of the P. aeruginosa tol-oprL gene cluster and determined its nucleotide sequence. This cluster was found to consist of seven genes in the order orf1 tolQ tolR tolA tolB oprL orf2. Transcriptional analysis of this gene cluster was performed by detecting the presence of mRNAs spanning adjacent genes as well as by using a promoterless lacZ reporter gene fused to each of the seven genes contained in the tol-oprL locus. The results show that there are three major transcriptional units or operons in this region, orf1-tolQRA, tolB, and oprL-orf2, in contrast to the E. coli tol-pal region, where there are only two operons, orf1-tolQRA and tolB-pal-orf2. Analysis of gene expression indicated that the tol-oprL genes of P. aeruginosa are both iron and growth phase modulated. The first operon, orf1-tolQRA, is iron regulated throughout growth, but iron-regulated expression of tolB and oprL fusions occurs only in late log phase. The expression of the three operons was significantly less repressed by iron in fur mutants than in the wild-type strain, suggesting the involvement of Fur in the iron regulation of all three operons. RegA is a positive yet nonessential regulator of tol-oprL expression.

Studies on the relationships between the synonymous codon usage and protein secondary structural units

The relationship between the synonymous codon usage and protein secondary structural elements (alpha helices and beta sheets) were reinvestigated by taking structural information of proteins from Protein Data Bank (PDB) and their corresponding mRNA sequences from GenBank for four different organisms E. coli, B. subtilis, S. cerevisiae, and Homo sapiens. It was observed that synonymous codon families have non-random codon usage, but there does not exist any species invariant universal correlation between the synonymous codon usage and protein secondary structural elements. The secondary structural units of proteins can be distinguished from the occurrences of bases at the second codon position.

Use of an attenuated leishmanial parasite as an immunoprophylactic and immunotherapeutic agent against murine visceral leishmaniasis

The ability of the leishmanial parasite UR6 to act as an immunoprophylactic and immunotherapeutic agent against Leishmania donovani infection in BALB/c mice was investigated. Unlike the virulent L. donovani AG83 (MOHOM/IN/1983/AG83), UR6 given through intracardiac route failed to induce visceral infection, but when it was injected subcutaneously, UR6 induced a short-lived and localized self-healing skin lesion. Priming of peritoneal macrophages with UR6 in vitro induced superoxide (O(2)(-)) generation, whereas similar experiments with virulent AG83 inhibited O(2)(-) generation. It was observed that priming of mice with either live or sonicated UR6 in the absence of any adjuvant provided strong protection against subsequent virulent challenge. Further, UR6-primed infected mice not only displayed a strong antileishmanial delayed-type hypersensitivity (DTH) response but also showed an elevated level of the serum antileishmanial immunoglobulin G2a (IgG2a) isotype, whereas infected mice failed to mount any antileishmanial DTH response and showed an elevated level of IgG1. This indicates that UR6 priming and subsequent L. donovani infection allowed the expansion of Th1 cells. Our studies indicate that UR6 has potential to be used as an immunoprophylactic and immunotherapeutic agent against experimental visceral leishmaniasis.

Studies on nutritional and oxygen requirements for production of L-asparaginase by Enterobacter aerogenes

The carbon and nitrogen sources most suitable for L-asparaginase production by Enterobacter aerogenes were selected and their concentrations optimized in shake-flask cultures. Sodium citrate (1.0%) and diammonium hydrogen phosphate (0.16%) proved to be the best sources of carbon and nitrogen, respectively. Nitrogen catabolite repression of enzyme formation was absent in this bacterium. Cultivation in a reactor showed that the dissolved oxygen level is the limiting factor for L-asparaginase production by E. aerogenes. Glucose was found to be a repressor of enzyme synthesis. Asparagine was absent intracellularly when the L-asparaginase level was high. An increase in the extracellular alanine level when the dissolved oxygen remained low indicated a shift from aerobic to fermentative metabolism.

Interferon-gamma- and lipopolysaccharide-induced tumor necrosis factor-alpha is required for nitric oxide production: tumor necrosis factor-alpha and nitric oxide are independently involved in the killing of Mycobacterium microti in interferon-gamma- and lipopolysaccharide-treated J774A.1 cells

A comparative study was done using J774A.1 and J774A.1-derived transfected cells (J774A.1 C.1) containing antisense tumor necrosis factor alpha (TNF-alpha) plasmid to determine the role of endogenous TNF-alpha on nitric oxide production as well as on the growth of Mycobacterium microti in interferon gamma (IFN-gamma)- and lipopolysaccharide (LPS)-treated cells. On stimulation with IFN-gamma and LPS a higher level of NO was observed in J774A.1 cells compared to J774A.1 C.1 which indicated that endogenous TNF-alpha is required for the production of NO. Comparing the effect of IFN-gamma and LPS on the intracellular growth of M. microti, the growth-reducing activity was higher in J774A.1 cells than in J774A.1 C.1 cells and was not completely abrogated in the presence of the nitric oxide inhibitor NG-methyl-L-arginine (L-NMA). J774A.1 C.1 cells infected with M. microti produced a significant amount of NO when exogenous TNF-alpha was added along with IFN-gamma and LPS and the concentration of intracellular bacteria decreased almost to that in IFN-gamma and LPS treated parental J774A.1 cells. Addition of exogenous TNF-alpha even in the presence of L-NMA in J774A.1 C.1 cells could also partially restore intracellular growth inhibition of M. microti caused by IFN-gamma and LPS. TNF-alpha is probably required for the production of NO in J774A.1 cells by IFN-gamma and LPS but TNF-alpha and NO are independently involved in the killing of intracellular M. microti with IFN-gamma and LPS.

Signal transduction mechanism in human neutrophil: comparative study between the zeta and beta-protein kinase isotypes

Role of protein kinase C (PKC) isotypes in the regulation of neutrophil function are not clearly known. In the present study we purified the beta-PKC and zeta-PKC isotypes from human neutrophil. Both the isotypes are immunoreactive only to their respective antibodies. Zeta-PKC was further confirmed by RT-PCR using specific primer. Co-factor requirements for both the kinases were found to be different when DG and ceramide were used as second messenger. Selective substrate specificities were determined for both beta and zeta-PKC using isotype specific pseudosubstrates viz., [Ser25]PKC[19-31] and [Ser119]PKC[113-130] respectively. Endogenous protein phosphorylation by purified beta-PKC and zeta-PKC showed their functional differences in neutrophil. Beta-PKC phosphorylated 13, 15, 19, 33, 36, 47, 80 and 92 kDa proteins and zeta-PKC phosphorylated 19, 22, 42, 47, 75 and 87 kDa proteins, only exception was the phosphorylation of 47 kDa protein which had been phosphorylated by both the kinases. Differences in phosphorylation between beta-PKC and zeta-PKC clearly indicate the selective role for these PKC isotypes in the activation sequences of neutrophil.

Gastropathy and defense mechanisms in common bile duct ligated portal hypertensive rats

Portal hypertensive gastropathy is associated with a broad spectrum of gastric mucosal damage inspite of decreased gastric acid secretion, suggestive of compromised endogenous protective mechanisms. To determine the mechanisms of damage in portal hypertensive gastropathy we measured lipid peroxidation, glutathione, antioxidant and lysosomal enzymes in gastric mucosal homogenates from male Wistar rats with elevated intrasplenic pulp pressure, eighteen days after common bile duct ligation. Thiobarbituric acid-reactive substances and lysosomal enzymes (beta-glucuronidase and acid phosphatase) were increased in the common bile duct ligated group as compared to the sham-operated group. The levels of antioxidant defense enzymes, superoxide dismutase, glutathione peroxidase, catalase and glutathione were decreased as compared to the sham-operated controls. Pre-operative vitamin E administration decreased mucosal lipid peroxidation increased the levels of antioxidant defense enzymes and lowered the lysosomal enzymes. The plasma vitamin E levels in this group were lower when compared to animals receiving it post-operatively. In conclusion, free radical and lysosomal enzyme mediated damage may play a role in portal hypertensive gastropathy.

Imaging of trabecular bone structure in osteoporosis

Osteoporosis is a metabolic bone disorder that is characterized by reduced bone mass and a deterioration of bone structure which results in an increased fracture risk. Since the disease is preventable, diagnostic techniques are of major importance. Standard techniques determine bone mineral density, whereas some of the newer techniques focus on trabecular structure. This article reviews structure analysis techniques in the diagnosis of osteoporosis. Imaging techniques applied to the assessment of trabecular bone structure include conventional radiography, magnification radiography, high-resolution CT (HRCT) and high-resolution MR imaging (HRMRI). The best results were obtained using high-resolution tomographic techniques. The highest spatial resolutions in vivo were achieved using HRMRI. The most common texture analysis techniques that have been used are morphological parameters (analogous to bone histomorphometry). Fractal dimension, co-occurrence matrices, mathematical filter techniques and autocorrelation functions are more complex techniques. Most of the studies evaluating structure analysis show that texture parameters and bone mineral density both predict bone strength and osteoporotic fractures, and that combining both techniques yields the best results in the diagnosis of osteoporosis.

Compositional correlation studies among the three different codon positions in 12 bacterial genomes

Compositional distributions in the three codon positions of the coding sequences of 12 fully sequenced prokaryotic genomes, which are publicly available, were investigated. A universal compositional correlation was observed in most of the genomes under investigation irrespective of their overall genomic GC contents. In all the genomes, the GC contents at the first codon positions are always greater than the overall GC contents of the genomes whereas the reverse is true in the case of second codon positions. GC contents at the third codon positions are higher than the overall genomic GC contents in high GC containing genomes, and the opposite situation was found in case of low GC genomes except for Helicobacter pylori. In high-GC rich genomes, the GC contents at the first + second codon positions are less than the GC contents at the third codon positions, and they are low in low-GC genomes except for Helicobacter pylori. The distributions of four bases at the three different positions were also investigated for all 12 organisms. It was observed that in high-GC genomes G is the most dominant base and in low-GC genomes A is the most dominant base in the first codon positions. But purine bases, i.e., (A + G), predominantly occur in the first codon position. In the second codon position, A is the most dominant base in most of the organisms and G is the least dominant base in all the organisms. There is no unique regular pattern of individual bases at the third codon positions; however, there are significant differences in the occurrences of (G + C) contents in the third codon positions among the different organisms. Calculations of dinucleotide frequencies in 12 different organisms indicate that in GC-rich genomes GG, GC, CC, and CG dinucleotides are the most dominant whereas the reverse is true in case of low-GC genomes. Biological implications of these results are discussed in this paper.

Intracellular replication of choleraphage straight phi92

The broad host range choleraphage straight phi92 contains a linear double-stranded DNA molecule of 68 kilobase (kb) pairs with 3' overhang cohesive ends. Following infection with phage straight phi92, the host macromolecular synthesis is shut off within the first 5 min, and synthesis of phage-specific DNA is detectable after 7 min of infection. At early times during infection, phage DNA is replicated in circular form and the synthesis is membrane associated. The closed circular form serves as the precursor for the synthesis of the mature phage DNA which is eventually packaged into the phage head. Pulse labeling of ultraviolet-irradiated infected cells at different times during infection has allowed identification of about 30 phage-specific proteins of which 6 are structural proteins. These proteins appear during the infection cycle in two distinct phases, early and late. Eighteen early and 12 late proteins have been identified.

Effect of antioxidant vitamin E as a protective factor in experimental atherosclerosis in rhesus monkeys

Atherosclerosis has been known for many years, yet its etiology remains unknown. Hypercholesterolemia is a major risk factor for atherosclerosis. The mechanism by which it triggers endothelial injury is not known. Since the role of the antioxidant vitamin E on experimental atherosclerosis is inconsistent, the present study was undertaken to evaluate platelet lipid peroxidation and the role of vitamin E (alpha-tocopherol) as protective factor in atherosclerosis in rhesus monkeys. A significant decrease in serum cholesterol and serum triglyceride levels was found in the group of animals which were reverted to stock diet along with vitamin E injections after 9 months of atherogenic diet feeding. Decreases in malonyldialdehyde levels and antioxidant enzyme activities were less significant in animals continued on an atherogenic diet feeding along with vitamin E as compared with animals fed a stock diet with vitamin E supplementation. The overall observations in this study suggest that antioxidant status and lipid peroxidation could be partly restored with vitamin E supplementation in experimental atherosclerosis. Damage to endothelial cells destroys their antithrombotic status and leads to fatal thrombosis. alpha-Tocopherol offers the best hope, but the question is how much of it should be administered for the prevention of atherosclerosis.

Estimation of oxidative products of nitric oxide (nitrates, nitrites) in preeclampsia

Oxidative products of nitric oxide, serum nitrates and nitrites were estimated in 50 primigravidas with preeclampsia and in 50 gestation and age-matched normotensive primigravidas. Thirty three (66%) of these women had mild preeclampsia and 17 (34%) had severe preeclampsia. Serum nitrate and nitrite levels were significantly higher in preeclamptic women (nitrates - 15 +/- 1.17; nitrites - 11.82 +/- 1.16 micromol/L) than in the normotensive pregnant women (nitrates 11.82 +/- 1.16; nitrites - 5.08 +/- 0.47 micromol/L, p < 0.001). In preeclamptic women, serum nitrate and nitrite levels correlated with the severity of the disease (mild preeclampsia nitrate - 14.46 +/- 1.98; nitrite 6.21 +/- 0.84 micromol/L, severe preeclampsia nitrate - 16.65 +/- 3.64; Nitrite - 6.87 +/- 1.56 micromol/L). In preeclampsia there was significant positive correlation between nitrate and nitrite levels and diastolic blood pressure and proteinuria.

Unsaturated fatty acid-activated protein kinase (PKx) from goat testis cytosol

The cytosolic fraction of goat cauda epididymis possesses a protein kinase (PKx) activity which is stimulated by a number of unsaturated fatty acids of which arachidonic acid is the best activator in absence of cAMP or Ca(2+). Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and diacylglycerol have no effect either alone or in combination. The membrane fraction does not show any appreciable kinase activity even after detergent treatment. PKx migrates as a single band of apparent molecular mass of 116 kDa on 10% SDS-PAGE after sequential chromatographic separation on DEAE-cellulose, phenyl-Sepharose, high-Q anion exchange and protamine-agarose affinity column. PKx phosphorylates histone H1, histone IIIs and protamine sulfate, but not casein. However, the best phosphorylation was obtained with a substrate based on PKC pseudosubstrate sequence (RFARKGSLRQKNV). The kinase phosphorylates two endogenous cytosolic proteins of 60 and 68 kDa. Ser residues are primarily phosphorylated although a low level of phosphorylation is observed on Thr residues also. Ca(2+) and Mn(2+) inhibit PKx activity in the micromolar range. Staurosporine is found to inhibit the PKx activity to a significant level at sub-nanomolar concentration. Lyso-phosphatidylcholine and certain detergents at very low concentrations (<0.05%) stimulate enzyme activity to some extent. The immuno-crossreactivity study with antibody against different PKC isotypes suggests that the protein kinase under study is not related to any known PKC family. Even the antibody against PKN (a related protein kinase reported in rat testis found to be activated by arachidonic acid) does not cross-react with this protein kinase. Hence we believe that the protein kinase (PKx) reported here is different even from the PKN of rat testis. The phosphorylation of endogenous proteins by the protein kinase may be involved in cell regulation including fertility regulation and signal transduction.

Calcium metabolism in pre-eclampsia

OBJECTIVES

To study calcium metabolism in pre-eclampsia and normotensive gravid women.

METHOD

Ten milliliters of heparinized blood samples and 24-h urine samples were collected from 50 pre-eclamptic and 50 normotensive primigravidae. Blood samples were studied for calcium uptake, intracellular calcium level and calcium-dependent adenosine triphosphatase activity of red blood cell ghost. Urinary calcium excretion was estimated from the 24-h urine samples. These values were compared in the two groups.

RESULTS

The mean gestational age at recruitment was similar in both the groups. The mean maternal age was 24.28 +/- 2.41 years in pre-eclamptic and 23.48 +/- 4.16 years in normotensive women. In pre-eclampsia 24-h urinary calcium excretion (71.20 +/- 22.95 mg/day) and calcium-dependent ATPase activity (10.78 +/- 2.40 nmol/Pi/mg protein/min) was significantly lower compared to normotensive primigravidae (calcium excretion = 189.24 +/- 57.06 mg/day; Ca2+-dependent ATPase = 12.64 +/- 2.42 nmolPi/mg /protein per min; P < 0.001). Intracellular calcium levels and calcium uptake at 10 min by red blood cells were significantly higher in pre-eclampsia (P < 0.05). Calcium uptake by red blood cells at 20 and 30 min was similar in both groups.

CONCLUSION

Pre-eclampsia is associated with increased levels of intracellular calcium, decreased calcium-dependent ATPase activity of erythrocytes and hypocalciuria.

Different cytokine profiles in cryptogenic fibrosing alveolitis and fibrosing alveolitis associated with systemic sclerosis: a quantitative study of open lung biopsies

Differences in the inflammatory response and prognosis of cryptogenic fibrosing alveolitis (CFA) and that associated with systemic sclerosis (FASSc) are beginning to emerge. It is hypothesized that these differences may be reflected in a distinct pattern of T-helper (Th)-1 and Th-2-type cytokines. Open lung biopsies were obtained from clinically well-documented cases of CFA and FASSc and, as a control, compared with grossly and histologically normal parenchyma obtained from smokers whose lungs were resected for cancer (n=5 in each group). In situ hybridization (ISH) was applied to the samples using anti-sense and sense 35S-labelled riboprobes to detect messenger ribonucleic acid (mRNA) for interleukins (IL)-2, IL-4, IL-5 and interferon (IFN)-gamma. Between 52-91% of cells expressing the cytokines studied were present in the alveolar interstitium rather than in lumenal cells or the alveolar epithelial lining. The highest values for all four cytokines were present in the patients with FASSc, i.e., 22-39 ISH positive cells x mm(-2) alveolar tissue compared with 1-19 cells x mm(-2) and 4-5 cell x mm(-2) in CFA and control subjects, respectively. Whereas the proportions of the four cytokines in FASSc were similar to the control subjects, IL-4 and IL-5 predominated significantly in CFA (p<0.001). For example, the ratio of IL-5 to IFN-gamma was 22:1 in CFA, significantly higher than in the cases with FASSc (2:1) or the control subjects (4:1) (p<0.05). In conclusion, cryptogenic fibrosing alveolitis is an inflammatory condition which is characterized, like asthma, by a predominance of gene expression for T-helper-2-type regulatory cytokines, whereas cryptogenic fibrosing alveolitis associated with systemic sclerosis appears to have a distinct mixed T-helper-1/T-helper-2 functional phenotype and a greater number of cells expressing each of these pro-inflammatory cytokines.

Measurement of intraspecimen variations in vertebral cancellous bone architecture

A three-dimensional technique was developed for the quantification of the number and cross-sectional geometry of individual trabeculae oriented along a given direction. As an example application, the number of vertical and horizontal trabeculae and their respective cross-sectional geometry were determined for a set of six vertebral cancellous bone specimens (L3-L4 female vertebral bodies; age range 39-63 years). Three-dimensional optical images at a spatial resolution of 20 microm were obtained using an automated serial milling technique. The thickness distributions were generally right skewed. The mean true thickness for both the vertically and horizontally oriented trabeculae showed a strong relationship with volume fraction (vertical: r2 = 0.86; p < 0.05; horizontal: r2 = 0.80; p < 0.05), and mean trabecular thickness (Tb.Th.) (vertical: r2 = 0.81; p < 0.05; horizontal: r2 = 0.72; p < 0.05). The horizontal trabeculae were greater in number and were thinner than the vertical trabeculae. The coefficient of variation of the intraspecimen vertical trabecular thicknesses ranged from 25% to 42%, and showed a weak, albeit insignificant, positive correlation with volume fraction (r2 = 0.46). The findings demonstrated substantial intraspecimen variations exist in trabecular thickness that are not related to volume fraction. Further studies are recommended to determine the potential role of such intraspecimen variations in architecture on biomechanical properties.