Morphine Stimulates Mesangial Cell TNF-α and Nitrite Production

Background: Intravenous opiate abusers are susceptible to develop heroin and HIV-associated nephropathies; however, the role of opiates in the development of these kidney lesions is not clear. Patients with opiate addiction are prone to recurrent infections. Methods: The effect of morphine was studied on the generation of TNF- with or without LPS (lipopolysaccharide) by cultured mouse mesangial cells. In addition, the effect of morphine was evaluated on mesangial cell nitrite production. To evaluate the role of opiate receptors, we studied the effect of naloxone and naltrexone on mesangial cell TNF- and nitrite production. To determine the role of TNF- on mesangial cell nitrite production, we examined the effect of anti-TNF- antibody on morphine-induced nitrite production. Assay of TNF- and nitrite production was carried by ELISA and Griess method respectively. Results: Morphine alone did not enhance the generation of TNF- by mesangial cells, however, an enhanced (P < 0.001) TNF- production was observed when mesangial cells were first treated with morphine for 18 h and then activated further with LPS. Maximum release of TNF- was seen at a concentration of 10^–12 M of morphine. Opiate receptor antagonists (naloxone and naltrexone) inhibited the effect of morphine. Morphine also amplified (P < 0.0002) the effect of LPS on mesangial cell nitrite production. Anti-TNF- antibody attenuated morphine induced nitrite generation. Conclusion: We conclude that morphine stimulates the generation of TNF- by LPS-activated mesangial cells. This effect of morphine seems to be opiate receptor mediated and has a downstream effect in the form of mesangial cell nitrite generation. The present in vitro study provides the basis for a hypothesis that morphine may be playing a role in the development of heroin and HIV-associated nephropathies.     

Direct detection and identification of Mycobacterium tuberculosis and Mycobacterium bovis in bovine samples by a novel nested PCR assay: correlation with conventional techniques

Mycobacterium tuberculosis and M. bovis infect animals and humans. Their epidemiologies in developed and developing countries differ, owing to differences in the implementation of preventive measures (World Health Organization, 1999). Identification and differentiation of these closely related mycobacterial species would help to determine the source, reservoirs of infection, and disease burden due to diverse mycobacterial pathogens. The utility of the hupB gene (Rv2986c in M.tuberculosis, or Mb3010c in M.bovis) to differentiate M. tuberculosis and M. bovis was evaluated by a PCR-restriction fragment length polymorphism (RFLP) assay with 56 characterized bovine isolates (S. Prabhakar et al., J. Clin. Microbiol. 42:2724-2732, 2004). The degree of concordance between the PCR-RFLP assay and the microbiological characterization was 99.0% (P < 0.001). A nested PCR (N-PCR) assay was developed, replacing the PCR-RFLP assay for direct detection of M. tuberculosis and M. bovis in bovine samples. The N-PCR products of M. tuberculosis and M. bovis corresponded to 116 and 89 bp, respectively. The detection limit of mycobacterial DNA by N-PCR was 50 fg, equivalent to five tubercle bacilli. M. tuberculosis and/or M. bovis was detected in 55.5% (105/189) of the samples by N-PCR, compared to 9.4% (18/189) by culture. The sensitivities of N-PCR and culture were 97.3 and 29.7, respectively, and their specificities were 22.2 and 77.7%, respectively. The percentages of animals or samples identified as infected with M.tuberculosis or M. bovis by N-PCR and culture reflected the clinical categorizations of the cattle (P of <0.05 to <0.01). Mixed infection by N-PCR was detected in 22 animals, whereas by culture mixed infection was detected in 1 animal.     

Neurological Manifestations of COVID-19 Feature T Cell Exhaustion and Dedifferentiated Monocytes in Cerebrospinal Fluid

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The immunoregulatory role of bone marrow. III. Further characterization of the suppressor cell and its mode of action

In vitro primary antibody responses of spleen cells can be suppressed in a dose-dependent manner by the addition of bond marrow cells (BMC). This suppression was not abrogated by treatment of BMC with anti-Thy 1, anti-Lyt nor with anti-I-J antisera and complement. Furthermore, preculture of BMC with the synthetic thymic pentapeptide (TP5) or Soluble Thymic Factor (STF) before anti-Thy-1 treatment was similarly ineffective in removing the suppressor cell activity. Similarly, treatment of BMC with polyvalent anti-immunoglobulin serum or anti-Ia antiserum and complement failed to remove the suppressor activity. However, preparations of anti-H-2 and anti-stem-cell antisera were capable of significantly decreasing the suppressive ability of BMC. BMC were also shown to be capable of suppressing antibody responses induced by the polyclonal activators dextran sulphate (DxS), lipopolysaccharide (LPS) and purified protein derivative from tubercle bacilli (PPD). The non-specificity of this suppressor coupled with the absence of well-defined antigen on its surface may suggest that this cell represents a basic level of immune regulation.     

The floating knee. 40 cases of ipsilateral fractures of the femur and the tibia

Summary Floating knee is the term used to describe simultaneous fractures of the femur and tibia in the same limb. Thirty nine patients, with 40 such injuries, are presented with a follow up interval of six months to five years. The final functional result was poor if the femoral fracture was situated in the condylar flare and the results were comparatively better in those cases treated by cast bracing or when the fracture of the femur was stabilised internally. In all cases the fracture of the tibia was treated conservatively.

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Résumé Sous le terme de «genou flottant» les auteurs décrivent les fractures simultanées du fémur et du tibia au niveau du même membre. Ils présentent 40 lésions de ce type, chez 39 sujets, avec un recul compris entre six mois et cinq ans. Le résultat fonctionnel est médiocre lorsque le siège de la fracture du fémur est juxta-articulaire. Comparativement, les résultats sont meilleurs lorsque la fracture du fémur a été immobilisée dans une attelle plâtrée ou stabilisée par ostéosynthèse. Toutes les fractures du tibia ont été traitées orthopédiquement.

     

Response of the ENPP1-Deficient Skeletal Phenotype to Oral Phosphate Supplementation and/or Enzyme Replacement Therapy: Comparative Studies in Humans and Mice

Inactivating mutations in human ecto-nucleotide pyrophosphatase/phosphodiesterase-1 (ENPP1) may result in early-onset osteoporosis (EOOP) in haploinsufficiency and autosomal recessive hypophosphatemic rickets (ARHR2) in homozygous deficiency. ARHR2 patients are frequently treated with phosphate supplementation to ameliorate the rachitic phenotype, but elevating plasma phosphorus concentrations in ARHR2 patients may increase the risk of ectopic calcification without increasing bone mass. To assess the risks and efficacy of conventional ARHR2 therapy, we performed comprehensive evaluations of ARHR2 patients at two academic medical centers and compared their skeletal and renal phenotypes with ENPP1-deficient Enpp1^asj/asj mice on an acceleration diet containing high phosphate treated with recombinant murine Enpp1-Fc. ARHR2 patients treated with conventional therapy demonstrated improvements in rickets, but all adults and one adolescent analyzed continued to exhibit low bone mineral density (BMD). In addition, conventional therapy was associated with the development of medullary nephrocalcinosis in half of the treated patients. Similar to Enpp1^asj/asj mice on normal chow and to patients with mono- and biallelic ENPP1 mutations, 5-week-old Enpp1^asj/asj mice on the high-phosphate diet exhibited lower trabecular bone mass, reduced cortical bone mass, and greater bone fragility. Treating the Enpp1^asj/asj mice with recombinant Enpp1-Fc protein between weeks 2 and 5 normalized trabecular bone mass, normalized or improved bone biomechanical properties, and prevented the development of nephrocalcinosis and renal failure. The data suggest that conventional ARHR2 therapy does not address low BMD inherent in ENPP1 deficiency, and that ENPP1 enzyme replacement may be effective for correcting low bone mass in ARHR2 patients without increasing the risk of nephrocalcinosis. © 2021 American Society for Bone and Mineral Research (ASBMR).