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Chaudry Nasir Majeed,1 Christopher D Ma,2 Ted Xiao,3 Sean Rudnick,1 Herbert L Bonkovsky1 1Department of Internal Medicine, Section on Gastroenterology and Hepatology, Wake Forest School of Medicine, Winston-Salem, NC, USA; 2Wake Forest University School of Medicine, Winston-Salem, NC, USA; 3Department of Internal Medicine, Internal Medicine Residency Program, Wake Forest School of Medicine, Winston-Salem, NC, USACorrespondence: Chaudry Nasir Majeed, Department of Internal Medicine, Section on Gastroenterology and Hepatology, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157, USA, Tel +1 (336) 713-7311, Fax +1 (336) 713-7322, Email cmajeed@wakehealth.eduAbstract: Small interfering ribonucleic acids [siRNAs] are short ribonucleic acid (RNA) fragments cleaved from double-stranded RNA molecules that target and bind to specific sequences on messenger RNA (mRNA), leading to their destruction. Therefore, the siRNA down-regulates the formation of selected mRNAs and their protein products. Givosiran is one such siRNA that uses this mechanism to treat acute hepatic porphyrias. Acute hepatic porphyrias are a group of rare, inherited metabolic disorders, characterized by acute potentially life-threatening attacks as well as chronic symptoms with a negative impact on quality of life. It has four types, each associated with distinct enzyme defects in the heme biosynthesis pathway in the liver. By targeting the expression of hepatic 5-aminolevulinic acid [ALA] synthase-1 [ALAS1], givosiran can down-regulate levels of toxic metabolites, leading to biochemical and clinical improvement. Givosiran selectively targets hepatocytes due to its linkage to N-acetylgalactosamine (GalNac) leading to its selective uptake via asialoglycoprotein receptors (ASGPR). We provide an up-to-date literature review regarding givosiran in the context of a clinical overview of the porphyrias, an overview of siRNAs for therapy of human disorders, the design and development of givosiran, key clinical trial results of givosiran for prevention of acute porphyric attacks, emerging concerns regarding chronic use of givosiran, and the overall management of acute hepatic porphyrias. These insights are important not only for the management of acute hepatic porphyrias but also for the emerging field of siRNAs and their role in novel therapies for various diseases.Keywords: givosiran, small interfering RNA’s, siRNAs, 5- (or δ)-aminolevulinic acid synthase 1 (ALAS1) expression inhibitors, porphyrias

Rhinoviruses are major causes of morbidity in patients with respiratory diseases; however, their modes of transmission are controversial. We investigated detection of airborne rhinovirus in office environments by polymerase chain reaction technology and related detection to outdoor air supply rates. We sampled air from 9 A.M. to 5 P.M. each workday, with each sample run for 1 work week. We directly extracted RNA from the filters for nested reverse transcriptase-polymerase chain reaction analysis of rhinovirus. Nasal lavage samples from building occupants with upper respiratory infections were also collected. Indoor carbon dioxide (CO2 concentrations were recorded every 10 minutes as a surrogate for outdoor air supply. To increase the range of CO2 concentrations, we adjusted the outdoor air supply rates every 3 months. Generalized additive models demonstrated an association between the probability of detecting airborne rhinovirus and a weekly average CO2 concentration greater than approximately 100 ppm, after controlling for covariates. In addition, one rhinovirus from a nasal lavage contained an identical nucleic acid sequence similar to that in the building air collected during the same week. These results suggest that occupants in buildings with low outdoor air supply may have an increased risk of exposure to infectious droplet nuclei emanating from a fellow building occupant. [ABSTRACT FROM AUTHOR]

Describes a study to determine whether the administration of recombinant human erythropoietin increases the amount of autologous blood that can be collected before surgery. Study details; Results; Conclusion.

In two phase I-II trials, 33 patients were given recombinant interferon alpha-2 daily at dosages of 3, 10, 30, 50, or 100 MU/d for up to 4 weeks by intramuscular or intravenous routes. Dose-limiting toxicities, including neutropenia, elevated hepatocellular enzyme levels, fatigue, and disturbed mentation, correlated with differing serum pharmacokinetics of interferon in the two trials. In the intramuscular study, dose-limiting toxicity occurred at all dosages greater than 10 MU/d, at a median of 6 to 9 days of treatment. In the intravenous dose-study, limiting toxicity was seen only at dosages of 100 MU/d, at a median of day 8. Twenty-three patients had metastatic melanoma and 4 had objective partial or complete responses at dosages of 10 to 50 MU/d in the first month. Two patients with complete responses are free of tumor after 2.5 years of follow-up. A fifth patient had delayed complete regression, requiring 1 year to achieve maximum response, but remains free of disease at 26 months since entry to the trial. Interferon had antitumor activity against melanoma by both routes tested, at dosages of 10 to 50 MU/d. [ABSTRACT FROM AUTHOR]

Abstract Background Rhinovirus, the most common cause of upper respiratory tract infections, has been implicated in asthma exacerbations and possibly asthma deaths. Although the method of transmission of rhinoviruses is disputed, several studies have demonstrated that aerosol transmission is a likely method of transmission among adults. As a first step in studies of possible airborne rhinovirus transmission, we developed methods to detect aerosolized rhinovirus by extending existing technology for detecting infectious agents in nasal specimens. Methods We aerosolized rhinovirus in a small aerosol chamber. Experiments were conducted with decreasing concentrations of rhinovirus. To determine the effect of UV irradiation on detection of rhinoviral aerosols, we also conducted experiments in which we exposed aerosols to a UV dose of 684 mJ/m2. Aerosols were collected on Teflon filters and rhinovirus recovered in Qiagen AVL buffer using the Qiagen QIAamp Viral RNA Kit (Qiagen Corp., Valencia, California) followed by semi-nested RT-PCR and detection by gel electrophoresis. Results We obtained positive results from filter samples that had collected at least 1.3 TCID50 of aerosolized rhinovirus. Ultraviolet irradiation of airborne virus at doses much greater than those used in upper-room UV germicidal irradiation applications did not inhibit subsequent detection with the RT-PCR assay. Conclusion The air sampling and extraction methodology developed in this study should be applicable to the detection of rhinovirus and other airborne viruses in the indoor air of offices and schools. This method, however, cannot distinguish UV inactivated virus from infectious viral particles.

Abstract Background A previous observational study detected a strong positive relationship between sick leave absences and carbon dioxide (CO2) concentrations in office buildings in the Boston area. The authors speculated that the observed association was due to a causal effect associated with low dilution ventilation, perhaps increased airborne transmission of respiratory infections. This study was undertaken to explore this association. Methods We conducted an intervention study of indoor CO2 levels and sick leave among hourly office workers employed by a large corporation. Outdoor air supply rates were adjusted periodically to increase the range of CO2 concentrations. We recorded indoor CO2 concentrations every 10 minutes and calculated a CO2 concentration differential as a measure of outdoor air supply per person by subtracting the 1–3 a.m. average CO2 concentration from the same-day 9 a.m. – 5 a.m. average concentration. The metric of CO2 differential was used as a surrogate for the concentration of exhaled breath and for potential exposure to human source airborne respiratory pathogens. Results The weekly mean, workday, CO2 concentration differential ranged from 37 to 250 ppm with a peak CO2 concentration above background of 312 ppm as compared with the American Society of Heating, Refrigeration and Air-conditioning Engineers (ASHRAE) recommended maximum differential of 700 ppm. We determined the frequency of sick leave among 294 hourly workers scheduled to work approximately 49,804.2 days in the study areas using company records. We found no association between sick leave and CO2 differential Conclusions The CO2 differential was in the range of very low values, as compared with the ASHRAE recommended maximum differential of 700 ppm. Although no effect was found, this study was unable to test whether higher CO2 differentials may be associated with increased sick leave.