Paternal preconception exposure to chronic morphine alters respiratory pattern in response to morphine in male offspring

The clinical use of opioids is restricted by its deleterious impacts on respiratory system. Gaining a better understanding of an individual's susceptibility to adverse opioid effects is important to recognize patients at risk. Ancestral drug addiction has been shown to be associated with alterations in drug responsiveness in the progenies. In the current study, we sought to evaluate the effects of preconception paternal morphine consumption on respiratory parameters in response to acute morphine in male offspring during adulthood, using plethysmography technique. Male Wistar rats administered 10 days of increasing doses of morphine in the period of adolescence. Thereafter, following a 30-day abstinence time, adult males copulated with naïve females. The adult male offspring were examined for breathing response to morphine. Our results indicated that sires who introduce chronic morphine during adolescence leads to increase irregularity of respiratory pattern and asynchronization between inter-breath interval (IBI) and respiratory volume (RV) time series in male offspring. These findings provide evidence that chronic morphine use by parents even before pregnancy can affect respiratory pattern and response to morphine in the offspring.

An optimized animal model of lysolecithin induced demyelination in optic nerve; more feasible, more reproducible, promising for studying the progressive forms of multiple sclerosis

BACKGROUND

Multiple Sclerosis (MS) is a demyelinating disease leading to long-term neurological deficit due to unsuccessful remyelination and axonal loss. Currently, there are no satisfactory treatments for progressive MS somewhat due to the lack of an adequate animal model for studying the mechanisms of disease progression and screening new drugs.

NEW METHOD

Lysolecithin (LPC) or agarose-gel loaded LPC (AL-LPC) were applied to mouse optic nerve behind the globe via a minor surgery. Agarose loading was used to achieve longer time of LPC exposure and subsequently long-lasting demyelination.

RESULTS

The lesion sites characterized by luxol fast blue (LFB), FluoroMyelin, Bielschowsky's staining, and immunostaining showed extensive demyelination and axonal damage. The loss of Retinal ganglion cells (RGCs) in the corresponding retinal layer was shown by immunostaining and H&E staining. Visual evoked potential (VEP) recordings showed a significant increase in the latency of the P1 wave and a decrease in the amplitude of the P1N1 wave.

COMPARISON WITH EXISTING METHODS

The new approach with a very minor surgery seems to be more feasible and reproducible compared to stereotaxic LPC injection to optic chiasm. Our data revealed prolonged demyelination, axonal degeneration and RGCs loss in both AL-LPC and LPC groups; however, these pathologies were more extensive in the AL-LPC group.

CONCLUSION

The optimized model provides a longer demyelination time frame and axonal damage followed by RGC degeneration; which is of exceptional interest in investigating axonal degeneration mechanisms and screening the new drugs for progressive MS.

Bronchoconstriction Induces Structural and Functional Airway Alterations in Non-sensitized Rats

The impact of mechanical forces on pathogenesis of airway remodeling and the functional consequences in asthma remains to be fully established. In the present study, we investigated the effect of repeated bronchoconstriction induced by methacholine (MCh) on airway remodeling and airway hyperresponsiveness (AHR) in rats with or without sensitization to an external allergen. We provide evidence that repeated bronchoconstriction, using MCh, alone induces airway inflammation and remodeling as well as AHR in non-allergen-sensitized rats. Also, we found that the airways are structurally and functionally altered by bronchoconstriction induced by either allergen or MCh in allergen-sensitized animals. This finding provides a new animal model for the development of airway remodeling and AHR in mammals and can be used for studying the complex reciprocal relationship between bronchoconstriction and airway inflammation. Further studies on presented animal models are required to clarify the exact mechanisms underlying airway remodeling due to bronchoconstriction and the functional consequences.

Rhino-orbital zygomycosis secondary to Rhizopus oryzae in a renal transplant recipient successfully treated with liposomal amphotericin B

Rhino-orbital zygomycosis is usually an aggressive, fulminant and, at times, fatal disease that requires urgent medical and surgical treatment. We report a case of rhino-orbital zygomycosis caused by Rhizopus oryzae that developed in a 41-year-old male renal transplant recipient. He was diagnosed in the early post transplant period after anti-rejection therapy. The infection was successfully managed with liposomal amphotericin B and functional endoscopic sinus surgery.