Toxoplasma gondii in lactating animals: potential risk to milk consuming population in Khyber Pakhtunkhwa

Toxoplasma gondii is an intracellular zoonotic protozoan parasite usually infects human and animal worldwide. This study aimed to analyze the sero-prevalence of T. gondii in blood of lactating animals and human living in close proximity and also to detect Toxoplasma DNA in unpasteurized milk of the studied animals. A total of 233 blood and milk samples were collected from lactating animals, and 735 blood samples were taken from humans in District Upper Dir, Khyber Pakhtunkhwa, Pakistan. The blood samples were analyzed through ELISA while the milk samples were analyzed by PCR for the presence of T. gondii DNA. A standard questionnaire was introduced to collect the data from the participants. In animals, the reported sero-prevalence was 32.18% for IgM, 17.16% for IgG, and 6.4% for both IgM and IgG. The reported positivity for T. gondii DNA in milk was 14.44%, 34.8%, 20%, and 26% in sheep, goats, cows, and buffaloes, respectively. In the human blood samples, 9.8% were found positive for IgM and 11.2% for IgG while none of the samples was found positive for both IgM and IgG. Overall sero-prevalence reported in females was significantly higher than the male (p<0.05) poor hygiene condition (p < 0.0001) were the significant risk factors associated with T. gondii infections in animals. In conclusion, T. gondii infection is prevalent in lactating animals and humans using their raw milk in the study area. It is suggested that raw milk should be considered as a vehicle for the transmission of T. gondii to humans. Proper pasteurization of milk is very useful in limiting the transmission of infection. Awareness and control programs should be implemented to prevent the infection.

Cannabidiol Ameliorates Cognitive Function via Regulation of IL-33 and TREM2 Upregulation in a Murine Model of Alzheimer's Disease

There is a dire need for due innovative therapeutic modalities to improve outcomes of AD patients. In this study, we tested whether cannabidiol (CBD) improves outcomes in a translational model of familial AD and to investigate if CBD regulates interleukin (IL)-33 and triggering receptor expressed on myeloid cells 2 (TREM2), which are associated with improved cognitive function. CBD was administered to 5xFAD mice, which recapitulate early onset, familial AD. Behavioral tests and immunoassays were used to evaluate cognitive and motor outcomes. Our findings suggest that CBD treatment enhanced IL-33 and TREM2 expression, ameliorated the symptoms of AD, and retarded cognitive decline.

Food habits of indian crested porcupine (Hystrix indica) (Kerr 1792), in district Bagh, Azad Jammu and Kashmir

The Indian Crested Porcupine (Hystrix indica) is classified as an agricultural pest species. It feeds on plants and crops; hence, it is responsible for massive financial losses worldwide. The current study was conducted to assess the diet composition of Indian Crested Porcupine in District Bagh, Azad Jammu and Kashmir (AJ&K). Thus, fecal samples were collected and examined from different sampling sites. Reference slides of the material collected from the study area were prepared for identification of dietary components in fecal pellets. A total of 80 fecal samples were collected and processed. Percent relative frequencies (P.R.F.) were calculated for each plant species recovered from pellets. Data revealed that Indian Crested Porcupine consumed 31 plant species in its diet, among them Zea mays (34.31±7.76) was the most frequently selected species followed by Rumex obtusifolius (15.32±2.57) and Melia azedarach (12.83±4.79). The study revealed that the greatest diversity of (n=20) plant species were consumed in summer season while minimum (n=13) species were used during winter. Among the parts of plants, stem was highly consumed in spring (57.2%) as compared to seed in fall (36.7%) while spikes and leaf were the least recovered parts from the fecal matter. The Berger-Parker diversity index showed highly diversified food (10.92) in the summer time of the year as compared to the autumn season (2.95). This study provides a baseline for the diet preference of this pest in the study area. Based on current findings, a detailed investigation on damage assessment, exploration, habitat use and management of Indian Crested Porcupine in AJ&K has been recommended.

Formation of n- and p-type regions in individual Si/SiO2 core/shell nanowires by ion beam doping

A method for cross-sectional doping of individual Si/SiO₂ core/shell nanowires (NWs) is presented. P and B atoms are laterally implanted at different depths in the Si core. The healing of the implantation-related damage together with the electrical activation of the dopants takes place via solid phase epitaxy driven by millisecond-range flash lamp annealing. Electrical measurements through a bevel formed along the NW enabled us to demonstrate the concurrent formation of n- and p-type regions in individual Si/SiO₂ core/shell NWs. These results might pave the way for ion beam doping of nanostructured semiconductors produced by using either top-down or bottom-up approaches.

Towards athermal organic-inorganic guided mode resonance filters

We demonstrate guided-mode resonance filters featuring an amorphous TiO(2) layer fabricated by atomic layer deposition on a polymeric substrate. The thermal properties of such filters are studied in detail by taking into account both thermal expansion of the structure and thermo-optic coefficients of the materials. We show both theoretically and experimentally that these two effects partially compensate for each other, leading to nearly athermal devices. The wavelength shift of the resonance reflectance peak (< 1 nm) is a small fraction of the peak width (~11 nm) up to temperatures exceeding the room temperature by tens of degrees centigrade.

Mapping of a new SGBS locus to chromosome Xp22 in a family with a severe form of Simpson-Golabi-Behmel syndrome

Simpson-Golabi-Behmel syndrome (SGBS) is an X-linked overgrowth syndrome with associated visceral and skeletal abnormalities. Alterations in the glypican-3 gene (GPC3), which is located on Xq26, have been implicated in the etiology of relatively milder cases of this disorder. Not all individuals with SGBS have demonstrated disruptions of the GPC3 locus, which raises the possibility that other loci on the X chromosome could be responsible for some cases of this syndrome. We have previously described a large family with a severe form of SGBS that is characterized by multiple anomalies, hydrops fetalis, and death within the first 8 wk of life. Using 25 simple tandem-repeat polymorphism markers spanning the X chromosome, we have localized the gene for this disorder to an approximately 6-Mb region of Xp22, with a maximum LOD score of 3.31 and with LOD scores <-2.0 for all of Xq. These results demonstrate that neither the GPC3 gene nor other genes on Xq26 are responsible for all cases of SGBS and that a second SGBS locus resides on Xp22.

Purification and characterization of hemolysin from Porphyromonas gingivalis A7436

Porphyromonas gingivalis, a periodontal pathogen, has the ability to lyse erythrocytes. The hemolytic activity of P. gingivalis A7436 was purified as a 45-kDa protein from the culture supernatant of a 3-days old culture using nickel-nitrilotriacetic acid chromatography. Erythrocytes treated with purified P. gingivalis hemolysin showed the presence of pores and extracellular debris by scanning electron microscopy. Active immunization of mice with 15 micrograms hemolysin induced neutralizing antibodies to hemolysin. Heating at 60 degrees C and treatment with trypsin and dithiothreitol abolished hemolytic activity, while incubation with the protease inhibitor Na-p-tosyl-L-lysine chloromethyl ketone caused no effect. We report here for the first time purification of a hemolysin from P. gingivalis A7436. The amino acid sequence of an internal peptide of hemolysin showed sequence similarity with fimbrillin from P. gingivalis HG564. However, the amino acid composition of purified hemolysin was different from that of P. gingivalis fimbrillin. Also, the ability to lyse but not agglutinate erythrocytes and to bind to nickel-nitrilotriacetic acid differentiates P. gingivalis hemolysin from fimbrillin.

Invasion of aortic and heart endothelial cells by Porphyromonas gingivalis

Invasion of host cells is believed to be an important strategy utilized by a number of pathogens, which affords them protection from the host immune system. The connective tissues of the periodontium are extremely well vascularized, which allows invading microorganisms, such as the periodontal pathogen Porphyromonas gingivalis, to readily enter the bloodstream. However, the ability of P. gingivalis to actively invade endothelial cells has not been previously examined. In this study, we demonstrate that P. gingivalis can invade bovine and human endothelial cells as assessed by an antibiotic protection assay and by transmission and scanning electron microscopy. P. gingivalis A7436 was demonstrated to adhere to and to invade fetal bovine heart endothelial cells (FBHEC), bovine aortic endothelial cells (BAEC), and human umbilical vein endothelial cells (HUVEC). Invasion efficiencies of 0.1, 0.2, and 0. 3% were obtained with BAEC, HUVEC, and FBHEC, respectively. Invasion of FBHEC and BAEC by P. gingivalis A7436 assessed by electron microscopy revealed the formation of microvillus-like extensions around adherent bacteria followed by the engulfment of the pathogen within vacuoles. Invasion of BAEC by P. gingivalis A7436 was inhibited by cytochalasin D, nocodazole, staurosporine, protease inhibitors, and sodium azide, indicating that cytoskeletal rearrangements, protein phosphorylation, energy metabolism, and P. gingivalis proteases are essential for invasion. In contrast, addition of rifampin, nalidixic acid, and chloramphenicol had little effect on invasion, indicating that bacterial RNA, DNA, and de novo protein synthesis are not required for P. gingivalis invasion of endothelial cells. Likewise de novo protein synthesis by endothelial cells was not required for invasion by P. gingivalis. P. gingivalis 381 was demonstrated to adhere to and to invade BAEC (0.11 and 0.1% efficiency, respectively). However, adherence and invasion of the corresponding fimA mutant DPG3, which lacks the major fimbriae, was not detected. These results indicate that P. gingivalis can actively invade endothelial cells and that fimbriae are required for this process. P. gingivalis invasion of endothelial cells may represent another strategy utilized by this pathogen to thwart the host immune response.

Haemolysin from Mycobacterium avium complex isolates from AIDS patients

Cell-bound haemolytic activity was observed in isolates of Mycobacterium avium complex (MAC) from AIDS patients. M. avium type strains showed negligible activity. None of the culture supernates exhibited any haemolytic activity. Zwitterionic detergent 3-[(3-cholamidopropyl)-dimethyl-ammonio]-1-propanesulphonate (CHAPS) was used to extract haemolysin from ethanol-treated M. avium complex strain 101 (MAC101) cells. Haemolysin was isolated from CHAPS extract (CE) by metal affinity chromatography and identified as a 32-kDa protein by polyclonal antibodies raised against M. tuberculosis haemolysin. Treatment of CE with trypsin resulted in reduction of haemolytic activity, whereas heating at 100 degrees C for 10 min did not affect its activity. A similar 32-kDa haemolysin was extracted from cells of M. avium K128 which was isolated from a monkey infected with simian immunodeficiency virus (SIV). The haemolysin produced by M. avium strains isolated from AIDS patients may be associated with the pathogenesis of M. avium infection.

Isolation of a contact-dependent haemolysin from Mycobacterium tuberculosis

Contact-dependent haemolytic activity was observed with cells of Mycobacterium tuberculosis H(37)Rv and M. tuberculosis H(37)Ra, but not with those of M. bovis, M. bovis BCG and M. africanum. Culture filtrates of all these strains did not exhibit any haemolytic activity. M. tuberculosis H(37)Rv was subsequently used for the isolation of haemolysin. Haemolytic activity was retained in the cell debris even after sonication of the cells and treatment with Tween 80 and lysozyme. Solubilisation of haemolysin was possible only after the cell debris was washed with ethanol 70% and then treated with Tween 80 0.1%. The haemolysin thus obtained showed a micellar M(r) of >200000 by gel-filtration on Sephadex G-200 and a subunit M(r) of 66000 by SDS-PAGE. It was sensitive to trypsin but stable when heated at 60 degrees C for 10 min. Polyclonal serum raised in rabbits against the haemolysin neutralised the haemolytic activity. The N-terminal amino-acid sequence of the 66-kDa subunit of haemolysin showed identity with TB66, the 66-kDa secretory protein of M. tuberculosis, and 30% homology with the haemolysin A precursor of Vibrio cholerae. Phosphatidylglycerol inhibited lysis of sheep erythrocytes by the haemolysin and is probably the receptor for the haemolysin. Haemolysin not only lysed erythrocytes, but was also cytotoxic to human lung cells. It appears that, among the members of the M. tuberculosis complex, the cell-bound contact-dependent haemolysin/cytolysin is restricted to M. tuberculosis and it may be associated with the pathogenesis of M. tuberculosis.

Isolation of a 33-kDa protein antigen from delipidified Mycobacterium tuberculosis H37Rv

A 33-kDa protein (TB33) was isolated from a delipidated cell sonicate (CS) of Mycobacterium tuberculosis H37Rv (grown in Middlebrook 7H9 broth supplemented with glucose) using immobilized metal affinity chromatography (IMAC) on a nickel-nitrilotriacetic acid (Ni-NTA) column. TB33 could not be isolated from the culture filtrate (CF) of M. tuberculosis H37Rv using Ni-NTA. TB33 was recognized by monoclonal antibodies (mAb) known to react with proteins of M. tuberculosis with a molecular mass of 33/34 kDa; namely, mAb F126-5, F67-1 and F126-2. The N-terminal amino acid sequence of TB33 was found to be Xaa-Xaa-Thr-Pro-Ala-Asp-Val-Ser/Cys-Asn-Val-Ala-Ile and thus, shows identity with the N-terminal of antigen 84 of M. tuberculosis except for two mismatches. Antibodies to TB33 could be raised in mice by administering four injections of TB33 (40 micrograms total protein). Sera from tuberculosis patients reacted with TB33, while those from normal healthy individuals did not.

Immunoaffinity chromatographic isolation of a high molecular weight seroreactive protein from Mycobacterium leprae cell sonicate

The purpose of this study was to isolate Mycobacterium leprae antigen(s) by immunoaffinity chromatography using immunoglobulins from leprosy patients and from rabbit anti-M. leprae hyperimmune serum coupled to CNBr-Sepharose 4B. A high molecular weight (M(r)) M. leprae protein (MLP) with a subunit M(r) of 22,000 was isolated. MLP was recognized by monoclonal antibody MMPII1G4 which is known to react with MMPII, a 22 kDa protein of M. leprae. The N-terminal sequence of the 22 kDa subunit (Met-gln-gly-asp-pro-asp-val-leu-arg-leu-leu-asn-glu-gln-leu-thr) was identical to MMPII and to antigen D (bacterioferritin) of M. paratuberculosis. It showed 44% homology with N-terminal end of E. coli bacterioferritin. In ELISA, MLP showed 100% and 60% positivity with leprosy and TB sera respectively as compared to normal healthy sera. The role of bacterioferritin in M. leprae and the importance of MLP as an immunogen has been discussed.

Perinatal mortality in the Cape Province, 1989-1991

OBJECTIVE

To determine the number of deliveries, the low-birth-weight rate and the perinatal mortality rate at provincial and province-aided hospitals and clinics in each planning region of the Cape Province.

DESIGN

A record of the number of deliveries, low-birth-weight infants, stillbirths and early neonatal deaths in provincial and province-aided hospitals and clinics in each planning region of the Cape Province between 1 January 1989 and 31 December 1991.

SETTING

All provincial and province-aided hospitals and clinics in the Cape Province.

PARTICIPANTS

Hospital and clinic staff of all provincial and province-aided hospitals and clinics in the Cape Province.

MAIN OUTCOMES MEASURED

Number of deliveries, low-birth-weight infants, stillbirths and early neonatal deaths in each planning region of the Cape Province.

RESULTS

A total of 373,768 births were recorded during the 3-year period with a low-birth-weight rate of 14.7%, a stillbirth rate of 17.9 per 1,000 and an early neonatal mortality rate of 9.1 per 1,000. All rates differed widely between regions. The regions with the highest perinatal mortality rates were in the northern and eastern Cape.

CONCLUSION

The perinatal demographics of most regions in the Cape Province are typical of a developing country. Regions which have been identified as having the highest low-birth-weight, stillbirth and early neonatal mortality rates are in greatest need of improved perinatal health care.

Isolation of a 43 kDa protein from Mycobacterium tuberculosis H37Rv and its identification as a pyridine nucleotide transhydrogenase

A 43 kDa protein (TB43) was isolated from the cell sonicate (CS) of Mycobacterium tuberculosis H37Rv with immobilized metal affinity chromatography (IMAC) on a Ni-nitrilotriacetic acid column. Two-dimensional electrophoresis of the IMAC fraction showed a major spot with an M(r) of 43,000 and a pI of approximately 6.0. The N-terminal amino acid sequence of TB43 was met-arg-val-gly-ile-pro-asn-glu-thr-lys-asn-asn-glu-phe-arg-val-ala- ile-thr-pro-ala. It showed 86% homology with the N-terminal end of the alanine dehydrogenase of Myco. tuberculosis and 65% homology with the N-terminal end of the alpha-subunit of the Escherichia coli pyridine nucleotide transhydrogenase (Tsh). TB43 did not show any alanine dehydrogenase activity and did not react with monoclonal antibody (MAb) HBT10, which is known to recognize the 40 kDa alanine dehydrogenase of Myco. tuberculosis. It was also not recognized by MAb F29-29 which is known to react with a 43 kDa protein of Myco. tuberculosis complex. This protein exhibited strong Tsh activity. A similar 43 kDa protein showing Tsh activity was also isolated by IMAC from Myco. bovis CS. However, the pI of the protein was approximately 7.0. A similar protein could not be isolated from the CS or culture filtrate of Myco. bovis BCG and Myco. tuberculosis H37Ra. TB43 is a cell-associated pyridine nucleotide transhydrogenase and is distinct from the 40/44 kDa secreted alanine dehydrogenase of Myco. tuberculosis.

Skin reactivity and fibronectin-binding property of TB66 (66-kDa protein of Mycobacterium tuberculosis)

A 66-kDa protein (TB66) was purified from culture filtrate (CF) and cell sonicate (CS) of Mycobacterium tuberculosis H37Rv by immobilised metal affinity chromatography (IMAC) on a Ni-nitrilotriacetic acid (NTA) column. TB66 was found to be a fibronectin-binding protein as determined by ELISA and could be purified by affinity chromatography with fibronectin-Sepharose. A similar 66-kDa protein could be isolated also from M. bovis, M. bovis BCG, M. africanum and M. tuberculosis H37Ra by IMAC, but not from any other mycobacteria. The NH2-terminal amino-acid sequence of TB66 from H37Rv and M. bovis was identical and showed 85% homology with the N-terminal sequence of bovine serum albumin (BSA). A monoclonal antibody (MAb) OD4AG3 recognised a heat-stable and trypsin-sensitive epitope near the C-terminal end of TB66. This MAb also recognised the 66-kDa protein isolated from the other members of the M. tuberculosis complex. In tests of immunogenicity, TB66 elicited a delayed type hypersensitivity reaction in guinea-pigs immunised with either TB66 or with M. tuberculosis H37Rv. TB66 also elicited an antibody response in immunised guinea-pigs and stimulated murine macrophages to produce tumour necrosis factor.

Purification and partial characterisation of a novel 66-kDa seroreactive protein of Mycobacterium tuberculosis H37Rv

A seroreactive protein (TB66) was purified from culture filtrate (CF) and cell sonicate (CS) of Mycobacterium tuberculosis H37Rv by immobilised metal affinity chromatography (IMAC) on a Ni-nitrilotriacetic acid (NTA) column. The TB66 preparations obtained by IMAC contained predominantly a 66-kDa protein with a pI of c. 5.5 as determined by two-dimensional electrophoresis. TB66 was detected in the CF as early as 1 week of growth of H37Rv. The NH2-terminal amino-acid sequence showed 85% homology with the N-terminal sequence of bovine serum albumin (BSA) and 80% homology with human serum albumin. Amino-acid analysis indicated a difference in the amino-acid content of TB66 when compared to BSA, with an abundance of acidic amino acids. A monoclonal antibody (MAb) OD4AG3, raised in this laboratory against an M. avium complex (MAC 101) sonicate cross-reacting with H37Rv sonicate, recognised a heat-stable and trypsin-sensitive epitope of this protein. TB66 was also recognised by MAbs IT1 and IT20 which also react with the 14-kDa antigen of the M. tuberculosis complex. Antibodies against TB66 were present in the sera of 62 of 64 patients with tuberculosis; sera from normal healthy individuals showed no significant reactivity. TB66 appears to be a predominant secretory protein of M. tuberculosis and could play an important role in the pathogenesis of this organism.

Superoxide dismutase activity of Mycobacterium tuberculosis isolated from tuberculosis patients and the immunoreactivity of superoxide dismutase from M. tuberculosis H37Rv

OBJECTIVE

To determine the superoxide dismutase (SOD) activity from clinical isolates of Mycobacterium tuberculosis and to study the seroreactivity of SOD from M. tuberculosis H37Rv.

DESIGN

Crude cell extracts of 16 strains of M. tuberculosis isolated from tuberculosis (TB) patients were assayed for SOD activity. SOD from H37Rv was partially purified and characterized, and the seroreactivity was studied by ELISA using sera from 36 active pulmonary TB and 31 leprosy patients.

RESULTS

SOD activity was detected in all the 16 strains of M. tuberculosis and also in the medium of logarithmic and stationary cultures of H37Rv. SOD activity from H37Rv extract was not affected by 1 mM KCN or by 5 mM H2O2 and was only 20% inhibited by 10 mM NaN3, suggesting that it is a Mn-containing enzyme. SOD was partially purified from H37Rv extract by gel filtration chromatography as a tetramer of molecular weight (MW) of 80,000 and a subunit MW of approximately 23,000. A delayed type hypersensitivity was elicited by SOD in guinea pigs sensitized with H37Rv or M. leprae sonicate. ELISA using SOD as antigen indicated 100% positivity with TB sera, while 84% positivity was observed with leprosy sera. Western blotting with pooled TB and leprosy sera indicated the presence of antibodies to the 23 kD SOD protein.

CONCLUSION

Our data indicate that M. tuberculosis strains are rich in SOD, and the secretion of SOD may play a valuable role in the pathogenesis of M. tuberculosis.

Immunological evaluation of a 12-kilodalton protein of Mycobacterium tuberculosis by enzyme-linked immunosorbent assay

OBJECTIVE

To purify and study the seroreactivity of native and recombinant 12-kilodalton protein of Mycobacterium tuberculosis H37Rv.

DESIGN

M. tuberculosis H37Rv cells and Escherichia coli XL-1 containing the plasmid PRL4 encoding the M. tuberculosis heat shock protein GroES homolog were used as sources for the purification of native and recombinant 12 kD of M. tuberculosis respectively. The seroreactivity of the 12 kDs was studied by ELISA using sera from 35 leprosy and 25 active pulmonary tuberculosis (TB) patients, and from 10 normal healthy controls.

RESULTS

The 12 kD protein was purified from H37Rv extract (s12 kD) and from recombinant E. coli (r12 kD) by ultrafiltration and MonoQ fast pressure liquid chromatography (FPLC). Analysis of s12 kD and r12 kD by SDS-PAGE revealed a single protein band in both cases with an approximate molecular weight of 12,000 which was recognized by monoclonal antibody SA-12 in immunoblotting. Both the proteins exhibited a pI of approximately 4.6 by isoelectric focusing. Both the 12 kD proteins exhibited 96% positivity with TB sera as compared to normal control sera (P < 0.01). Only one serum sample from the 35 leprosy sera tested exhibited binding to both the s12 kD and r12 kD proteins. Delayed type hypersensitivity reaction to the 12 kD proteins was elicited in guinea pigs that had been immunized with H37Rv sonicate.

CONCLUSION

The 12 kD protein could be easily purified and could serve as a valuable serodiagnostic tool in the screening of TB cases from a large population in an endemic area.

Superoxide dismutase activity of Mycobacterium avium complex (MAC) strains isolated from AIDS patients

OBJECTIVE

To explore whether Mycobacterium avium complex (MAC) strains isolated from AIDS patients produce and secrete superoxide dismutase (SOD).

DESIGN

SOD was assayed in the crude extracts and in cell-free medium of 18 MAC strains (MAC 101, LR and SK strains) isolated from AIDS patients to determine intracellular and extracellular activity. The SODs were characterized by PAGE and by their sensitivity to azide, cyanide and hydrogen peroxide.

RESULTS

SOD activity was detected in cell extracts as well as in extracellular medium of all AIDS-MAC strains. PAGE demonstrated a single activity band for each strain, though there were differences in mobility. All LR strains demonstrated an activity band with Rf = 0.30, while SOD band for MAC 101 and for SK strains migrated further (Rf = 0.87). The differences in mobility correlated with differences in sensitivity to NaN3 and H2O2. The SOD activity of LR strains was irreversibly inhibited 100% by 5 mM H2O2, and exhibited greater sensitivity to NaN3, suggesting the presence of iron in the enzyme. The SOD activity of SK strains and MAC 101, however, was not inhibited by 5 mM H2O2 but was inhibited to a lesser extent by NaN3, which is characteristic of a manganese-containing SOD.

CONCLUSION

Our data indicate that MAC strains are rich in manganese- or iron-containing SOD, which could contribute to the organism's resistance to the oxidative burst of activated macrophages. The secretion of SOD may play an important role in the pathogenesis of MAC strains.

Comparative antigenic analysis of Mycobacterium avium complex (MAC) isolates from AIDS patients

Sonicates of several Mycobacterium avium complex (MAC) strains isolated from acquired immunodeficiency syndrome (AIDS) patients were characterized in order to study the prominent antigens of these strains. Sonicates of 6-week-old cultures were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. A major 12 kDa glycoprotein antigen was observed in all the sonicates along with other proteins ranging up to 100 kDa. Western blotting, using the 12 kDa M. leprae 'specific' murine monoclonal antibody (MAb) MLO6, indicated the presence of a determinant in the 12 kDa antigen (in all the MAC isolates studied) which was immunologically cross-reactive with the 12 kDa antigen of M. leprae. The transparent variant of MAC 101 also demonstrated MLO6 reactivity while the opaque variant did not. Polyclonal antiserum raised against MAC 101 sonicate reacted with all the MAC isolates in immunodiffusion. These observations point to the cross-reactivity between these strains and suggest that they possess a M. leprae 'specific' determinant on a cross-reacting component which could be involved in virulence.

Enzyme linked immunosorbent assay of a 12-kDa protein of Mycobacterium leprae with sera from leprosy patients

A low molecular weight protein was obtained from a sonicate of armadillo-derived Mycobacterium leprae cells and from a lambda gt11 phage lysate of Escherichia coli (specifying the M. leprae 12-kDa protein) by a single step of ultrafiltration. Both proteins had an approximate molecular weight of about 12,000 (by SDS-PAGE) and were recognized by the M. leprae 12-kDa-specific monoclonal antibody ML06 by immunoblotting. Sera from 79 leprosy patients across the clinical spectrum, 17 contacts, and 12 normal healthy individuals were screened in an enzyme-linked immunosorbent assay (ELISA) using the 12-kDa proteins as the antigens. Antibodies to the 12-kDa protein (from lysate as well as sonicate) were detected in patients' sera across the clinical spectrum (44%-100% positivity), while no detectable reactivity was observed with control or contact sera. Sera from patients who had undergone a year or more of chemotherapy exhibited no reactivity compared to those from patients with only 3-6 months of chemotherapy. The 12-kDa proteins were also recognized by rabbit hyper-immune M. leprae antiserum.

Sero-immunoreactivity of cloned protein antigens of Mycobacterium leprae

Sera from 173 leprosy patients with various types of disease (tuberculoid = TT, borderline tuberculoid = BT, borderline lepromatous = BL, and lepromatous = LL), 12 intrafamilial contacts, and 40 normal healthy individuals were assayed in an indirect enzyme-linked immunosorbent assay (ELISA) using Mycobacterium leprae antigens. Recombinant clones carrying M. leprae antigens, namely, Y3184 (12 kDa), Y3179 (18 kDa), Y3164 (28 kDa), Y3180 (36 kDa), and Y3178 (65 kDa) and a cell sonicate from armadillo-derived M. leprae were used for the study. A high degree of reactivity with the 65-kDa, 36-kDa, and 28-kDa protein lysates was observed in most of the sera from multibacillary patients, with a low degree of positivity with 18 kDa and 12 kDa. Only a few sera from paucibacillary patients showed positive reactions. The majority of the contacts' sera tested showed no reactivity with these antigens.

Immunoreactivity of a mammalian liver component with leprosy sera

Sera from 77 leprosy patients in various stages of infection--tuberculoid (TT), lepromatous (LL), borderline tuberculoid and borderline lepromatous--15 contacts and 21 normal healthy individuals, were assayed in an indirect enzyme-linked immunosorbent assay and dot enzyme immunoassay using ethanol-soluble and thermostable extract of liver as the antigen. The highest incidences of reaction were found in untreated LL patients (100%) and in TT patients (91%), while the sera from borderline patients showed a comparatively lower incidence (43%). Some of the sera from contacts of leprosy patients (6/15) also showed high reactivity. Assays using lecithin as an antigen did not exhibit any reaction.

Priorities for provision of health care services for children in the Cape Province

Geographical areas in the Cape Province are ranked by their need for resources for child health care as determined by several proxy indicators of child health. Low birthweight and perinatal mortality rates for 1989, infant and age-specific childhood death rates, as well as death rates for tuberculosis, gastroenteritis and measles for 1985 are used as indicators of need. The ten magisterial districts having the highest priority for resources are, in decreasing order of need: De Aar, Colesberg, Uitenhage, Sterkstroom, Gordonia, Prince Albert, Philipstown, Victoria West, Kirkwood and Richmond. Limitations in the data are: wide, unquantifiable confidence limits, non-independence of different indicators, lack of timeliness, and incomplete statistics. Despite these problems with the data there are several reasons for employing them. Firstly, the quality of the data is only likely to be improved if they are actually used, and, secondly, there is no alternative. Areas identified as high priority need investigation in situ because corrective action is required for either the data collection system, or child health. Recommendations for improvements in resource management in child health care are: regionalisation of a unitary health care service, more timely data collection in geographically standardised regions, introduction of management objectives, and resource allocation guided by health status indicators.

Malathion induced alterations in the lipid profile and the rate of lipid peroxidation in rat brain and spinal cord

Malathion, known as a low toxic pesticide, is frequently used in the third world. Neurotoxic manifestations of malathion were evaluated on various lipids and lipid peroxidation in different brain areas following intraperitoneal injections (150 mg/kg body weight for 7 consecutive days) to albino rats. Clinical investigations show that malathion produced hypomotor activity and hyperthermia. Lipid components were differently affected by this pesticide, where total lipids and phospholipids were diminished in the spinal cord and brain stem, respectively. Increased contents of cholesterol were found in the cerebellum and spinal cord. Also, total lipids were increased in the cerebellum. The cholesterol/phospholipids ratio was increased in the cerebellum, brain stem and spinal cord. Rate of lipid peroxidation was found to be increased in all parts of the brain following malathion intoxication.

Cimetidine and hepatic blood flow in polytrauma patients

Recent reports suggest that cimetidine acutely reduces liver blood flow in normal healthy subjects. To determine whether this finding is applicable to critically ill patients, we studied nine polytrauma patients admitted to a surgical ICU. All patients were being monitored with pulmonary artery catheters; all were stable with normal liver function. Liver blood flow was estimated by indocyanine green clearance, before and after administration of a single dose of 600 mg cimetidine. Hemodynamic variables were measured at the same times. Cimetidine did not significantly alter either hepatic blood flow or cardiovascular status in these critically ill patients.

An improved method for evaluation of blood coagulation in heparinized blood

A simple method designed to allow coagulation studies in heparinized blood was evaluated. Citrated plasma containing heparin was incubated with an anion-exchange resin commercially available in tablet form (Heparsorb). After centrifugation of the mixture, coagulation studies were carried out on the supernatant plasma. One heparin neutralizer (HN) tablet was capable of removing as much as 43 units of heparin from 1 ml plasma within 10 min of incubation. When normal plasma was exposed to the heparin neutralizer, little or no change in the activities of clotting factors XII, XI, VIII, VII, X, V, and II was observed. However, the resin caused a substantial (44%) loss of factor IX-activity from normal plasma. This loss of factor IX-activity was not observed with plasma from patients receiving coumadin therapy. The results of coagulation tests (aPTT, PT, TT) and determination of fibrinogen/fibrin degradation products performed with HN-treated plasmas from nine patients receiving heparin therapy for thromboembolic disease and seven patients undergoing cardiopulmonary bypass operations were virtually identical to those obtained for the same persons before heparin was administered. The method, which is suitable for the routine clinical laboratory, may be useful in the hemostatic evaluation of critically ill patients who experience bleeding complications while receiving heparin therapy, in the laboratory control of coumadin therapy during the heparin-coumadin overlap period, and in the rapid identification of heparin contamination of blood specimens as a cause of an unexplained aPTT prolongation.