The sensitivity of Na+, K+ ATPase as an indicator of blood diseases

BACKGROUND

Blood-related hereditary diseases are widespread in Eastern and SouthWestern regions of Saudi Arabia until recently. In this study, we used Na⁺, K⁺ATPase as an enzymatic indicator for the diagnosis of the diseases.

MATERIALS AND METHODS

Individuals with different blood diseases (iron deficiency (n=13), anemia (n=14), thalassemia (n=16) and sickle cell anemia (n=12) were studied for Na⁺, K⁺-ATPase activity in the plasma membrane of red blood cell and compared with those of the healthy ones (n=20) of the same age and gender living in Jeddah, Saudi Arabia.

RESULTS

There was a significant elevation in the specific activity of Na⁺, K⁺ATPase in individuals with anemia compared with those of control (0.0094 + 0.001 nmol / mg protein/min versus 0.0061 ± 0.001). On the other hand, there was a significant reduction in enzyme activity in thalassemia (0.0028 ± 0.002 nmol / mg protein/min) and sickle cell anemia cases (0.0042 ±0.001 nmol / mg protein/min) compared to the control group. The cut off value for Na⁺, K⁺ATPase activity is 0.005 µmol Pi/min-showing 94% sensitivity and 93% specificity for the differentiation of blood abnormality.

CONCLUSION

It can be recommended that the activity of Na⁺, K⁺-ATPase can be used for the diagnosis of individuals with blood diseases/disorders.

The ldh phylogeny for environmental isolates of Lactococcus lactis is consistent with rRNA genotypes but not with phenotypes

Lactate dehydrogenase (ldh) gene sequences, levels of 16S rRNA group-specific probe binding, and phenotypic characteristics were compared for 45 environmental isolates and four commercial starter strains of Lactococcus lactis to identify evolutionary groups best suited to cheddar cheese manufacture, ldh sequences from the environmental isolates showed high similarity to those from two groups of L. lactis used for industrial fermentations, L. lactis subsp. cremoris and subsp. lactis. Within each phylogenetically defined subspecies, ldh sequence similarities were greater than 99.1%. Strains with phenotypic traits formerly diagnostic for both subspecies were found in each ldh similarity group, but only strains belonging to L. lactis subsp. cremoris by both the newer, genetic and the older, superseded phenotypic criteria were judged potentially suitable for the commercial production of cheddar cheese. Identical evolutionary relationships were inferred from ldh sequences and from binding of subspecies-specific, 16S rRNA-directed oligonucleotide probes. However, groups defined according to these chromosomal traits bore no relationship to patterns of arginine deamination, carbon substrate utilization, or bacteriophage sensitivity, which may be encoded by cryptic genes or sexually transmissible genetic elements. Fourteen new L. lactis subsp. cremoris isolates were identified as suitable candidates for cheddar cheese manufacture, and 10 of these were completely resistant to three different batteries of commercial bacteriophages known to reduce starter activity.

A milk-based method for detecting antimicrobial substances produced by lactic acid bacteria

A new technique for the detection of antimicrobial substances produced by lactic acid bacteria has been developed. In this technique, milk agar plates were supplemented with tetrazolium chloride or tetrazolium blue dyes. Comparisons of milk agar assays with M17 agar plates indicated that, out of 30 bacterial strains, 13 strains produced bacteriocins or inhibitory substances that were detectable on milk agar plates but not on M17 agar plates. Multiple-strain lactococcal cultures are used in milk fermentations. To identify suitable strains to combine for industrial use, component strains must be tested for compatibility. The procedure described allows optimization of compatibility. The assay of putative producer and sensitive indicator strains using milk agar plates (11% nonfat dry milk plus .8% agar and .02% tetrazolium chloride or tetrazolium blue) provides an important tool to prevent allopathic interactions in mixed cultures.

Isolation of Lactococcus lactis subsp. cremoris from nature by colony hybridization with rRNA probes

Lactococcus lactis subsp. cremoris is widely used in the manufacture of fermented milk products. Despite numerous attempts, efforts to isolate new strains by traditional plating and identification methods have not been successful. Previously, we described oligonucleotide probes for 16S rRNAs which could be used to discriminate L. lactis subsp. cremoris from related strains. These probes were used in colony hybridization experiments to screen large numbers of colonies obtained from enrichment cultures. A total of 170 strains of L. lactis were isolated from six milk samples, two colostrum samples, and one corn sample by using oligonucleotide probe 212RLa specific for the species L. lactis. Fifty-nine of these isolates also hybridized to L. lactis subsp. cremoris-specific probe 68RCa, and 26 of the strains which hybridized to the L. lactis subsp. cremoris-specific probe had the L. lactis subsp. cremoris phenotype.

In vitro translation of diapause mRNA from the fat body of active and diapause larvae of the pink bollworm, Pectinophora gossypiella (Saunders)

A diapause associated protein (DAP) (M(r) 103,000) was isolated from the hemolymph and fat body of diapausing fourth instar larvae of the pink bollworm Pectinophora gossypiella. The protein has been named Pectinophora diapause protein (PDP). The in vitro translation peptide patterns of total RNA from the fat body of actively feeding fourth instar, wandering, prediapause, early diapause, mid-diapause, and late diapause larvae in rabbit reticulocyte lysates showed the presence of poly (A)+ RNA sequence of PDP. The antigen was immunoprecipitated by polyclonal antiserum. It was concluded that the transcription of the PDP gene in the fat body cells started in the late fourth instar larva and that the expression of this gene was regulated at the level of transcription in the fat body of diapausing larvae. Northern hybridization analysis revealed that wandering fourth instar larvae (diapause individuals) maintain a relatively low level of diapause message (mRNA/2.4 kb) in their fat body cells which may be necessary for the induction of diapause.

Analysis of the in vitro lymphoproliferative responses and antibody levels to the arc-5 antigen in patients with cystic hydatid disease

Using a commercially-available, purified, arc-5 antigen, we examined the in vitro proliferative responses of peripheral blood mononuclear cells from hydatid patients and from healthy controls. Antibody levels of different immunoglobulin classes were also measured against the same antigen, in sera of both groups. Our findings indicate that lymphocytes from healthy controls do not proliferate to the arc-5 antigen, whereas lymphocytes from the majority of patients do. The negative or weak responses observed among a few patients were not due either to increased release of prostaglandins in culture or to a lack of responsiveness to Interleukin-2. Antibodies of all three classes, G, M and A, measured by an ELISA, were elevated in sera of patients when compared with controls. However, only levels of specific IgG antibodies gave an excellent discrimination of the disease state and these were of diagnostic value. No direct or inverse correlations between lymphoproliferative responses and antibody levels were observed in either group, although a few patients with relatively low antibody titres demonstrated very high proliferative responses. The possible use of the proliferative assay as an adjunct to serology in the diagnosis of hydatid disease is indicated.

A new test for measuring diapause in the pink bollworm Pectinophora gossypiella Sunders

An ELISA test was developed to assay for the presence of a protein, pectinophorin, that is expressed only in diapausing last instar larvae of the pink bollworm, Pectinophora gossypiella Saunders. Use of the test provides a good estimation of the percent of diapause larvae in populations of pink bollworm in cotton fields in California and Arizona. All plow down dates are chosen before the majority of larvae enter diapause so as to eliminate as many overwintering survivors as possible. These dates may now be determined more precisely for any given field by use of the new ELISA procedure.

L-asparaginase-producing Streptomyces from the soil of Kuwait

Five actinomycete isolates (all belonged to the genus Streptomyces), capable of producing detectable amounts of L-asparaginase, were isolated from the soil of Kuwait after enrichment. The three most potent enzyme producers were identified as different strains of Streptomyces collinus. Factors affecting enzyme production by the strongest strain were examined. Synthetic media with asparagine as a nitrogen source stimulated more enzyme production than natural media. Starch and asparagine at final concentrations of 1 and 0.8%, respectively, were optimum for enzyme production. An initial pH of 8.5 for the growth medium and an incubation temperature of 28-30 degrees C in a static culture for 6 days stimulated enzyme production by the examined strain of Streptomyces collinus.