Total Hip Arthroplasty in Dyggve-Melchior-Clausen Syndrome: Literature Review and Case Report.

Dyggve-Melchior-Clausen (DMC) disease is a rare spondyloepiphyseal autosomal recessive disorder characterized by skeletal dysplasia and intellectual disability. Hip arthritis, often secondary to hip dysplasia, presents at an early age. Current literature suggests that osteotomies do not benefit DMC syndrome-associated hip disease but reports of total hip arthroplasty in these patients are lacking. We present a case of bilateral hip replacement in a 31-year-old patient with DMC syndrome. After planning the operation with the use of computed tomography, we chose to use a small-dimension porous cup along with an appropriately sized version control stem in order to address the unique acetabular and femoral deformities. In conclusion, we consider total hip replacement in DMC syndrome to be safe and effective in addressing a challenging hip pathology.

High-Throughput CAMP Assay (HiTCA): A Novel Tool for Evaluating the Vitamin D-Dependent Antimicrobial Response.

Vitamin D is known to modulate human immune responses, and vitamin D deficiency is associated with increased susceptibility to infection. However, what constitutes sufficient levels or whether vitamin D is useful as an adjuvant therapeutic is debated, much in part because of inadequate elucidation of mechanisms underlying vitamin D's immune modulatory function. Cathelicidin antimicrobial peptide (CAMP) has potent broad-spectrum activity, and the CAMP gene is regulated in human innate immune cells by active 1,25(OH)2D3, a product of hydroxylation of inactive 25(OH)D3 by CYP27B1-hydroxylase. We developed a CRISPR/Cas9-edited human monocyte-macrophage cell line containing the mCherry fluorescent reporter gene at the 3' end of the endogenous CAMP gene. The High Throughput CAMP Assay (HiTCA) developed here is a novel tool for evaluating CAMP expression in a stable cell line that is scalable for a high-throughput workflow. Application of HiTCA to serum samples from a small number of human donors (n = 10) showed individual differences in CAMP induction that were not fully accounted for by the serum vitamin D metabolite status of the host. As such, HiTCA may be a useful tool that can advance our understanding of the human vitamin D-dependent antimicrobial response, which is being increasingly appreciated for its complexity.

Essential Workers' COVID-19 Vaccine Hesitancy, Misinformation, and Informational Needs in the Republic of North Macedonia.

The COVID-19 pandemic has resulted in over 5.2 million deaths. Vaccine hesitancy remains a public health challenge, especially in Eastern Europe. Our study used a sample of essential workers living in the Republic of North Macedonia to: (1) Describe rates of vaccine hesitancy and risk perception of COVID-19; (2) Explore predictors of vaccine hesitancy; and (3) Describe the informational needs of hesitant and non-hesitant workers. A phone survey was administered in North Macedonia from 4−16 May 2021. Logistic regression explored associations of COVID-19 vaccine hesitancy with sociodemographic characteristics, non-COVID-19 vaccine hesitancy, previous diagnosis of COVID-19, and individual risk perception of contracting COVID-19. Chi-squared analyses compared differences in informational needs by hesitancy status. Of 1003 individuals, 44% were very likely to get the vaccine, and 56% reported some level of hesitancy. Older age, Albanian ethnicity, increased education, previous COVID-19 diagnosis, acceptance of other vaccines, and increased risk perception of COVID-19 infection were negatively associated with vaccine hesitancy. Results indicated significant differences in top informational needs by hesitancy status. The top informational needs of the hesitant were the freedom to choose to be vaccinated without consequences (57% vs. 42%, p < 0.01) and that all main international agencies recommended the vaccine (35% vs. 24%, p < 0.01).

Vitamin D Binding Protein and the Biological Activity of Vitamin D.

Vitamin D has a long-established role in bone health. In the last two decades, there has been a dramatic resurgence in research interest in vitamin D due to studies that have shown its possible benefits for non-skeletal health. Underpinning the renewed interest in vitamin D was the identification of the vital role of intracrine or localized, tissue-specific, conversion of inactive pro-hormone 25-hydroxyvitamin D [25(OH)D] to active 1,25-dihydroxyvitamin D [1,25(OH)2D]. This intracrine mechanism is the likely driving force behind vitamin D action resulting in positive effects on human health. To fully capture the effect of this localized, tissue-specific conversion to 1,25(OH)2D, adequate 25(OH)D would be required. As such, low serum concentrations of 25(OH)D would compromise intracrine generation of 1,25(OH)2D within target tissues. Consistent with this is the observation that all adverse human health consequences of vitamin D deficiency are associated with a low serum 25(OH)D level and not with low 1,25(OH)2D concentrations. Thus, clinical investigators have sought to define what concentration of serum 25(OH)D constitutes adequate vitamin D status. However, since 25(OH)D is transported in serum bound primarily to vitamin D binding protein (DBP) and secondarily to albumin, is the total 25(OH)D (bound plus free) or the unbound free 25(OH)D the crucial determinant of the non-classical actions of vitamin D? While DBP-bound-25(OH)D is important for renal handling of 25(OH)D and endocrine synthesis of 1,25(OH)2D, how does DBP impact extra-renal synthesis of 1,25(OH)2D and subsequent 1,25(OH)2D actions? Are their pathophysiological contexts where total 25(OH)D and free 25(OH)D would diverge in value as a marker of vitamin D status? This review aims to introduce and discuss the concept of free 25(OH)D, the molecular biology and biochemistry of vitamin D and DBP that provides the context for free 25(OH)D, and surveys in vitro, animal, and human studies taking free 25(OH)D into consideration.

The Role of Lipoproteins in Mycoplasma-Mediated Immunomodulation.

Mycoplasma infections, such as walking pneumonia or pelvic inflammatory diseases, are a major threat to public health. Despite their relatively small physical and genomic size, mycoplasmas are known to elicit strong host immune responses, generally inflammatory, while also being able to evade the immune system. The mycoplasma membrane is composed of approximately two-thirds protein and one-third lipid and contains several lipoproteins that are known to regulate host immune responses. Herein, the immunomodulatory effects of mycoplasma lipoproteins are reviewed. A better understanding of the immunomodulatory effects, both activating and evasive, of Mycoplasma surface lipoproteins will contribute to understanding mechanisms potentially relevant to mycoplasma disease vaccine development and treatment.

A novel rapid and reproducible flow cytometric method for optimization of transfection efficiency in cells.

Transfection is one of the most frequently used techniques in molecular biology that is also applicable for gene therapy studies in humans. One of the biggest challenges to investigate the protein function and interaction in gene therapy studies is to have reliable monospecific detection reagents, particularly antibodies, for all human gene products. Thus, a reliable method that can optimize transfection efficiency based on not only expression of the target protein of interest but also the uptake of the nucleic acid plasmid, can be an important tool in molecular biology. Here, we present a simple, rapid and robust flow cytometric method that can be used as a tool to optimize transfection efficiency at the single cell level while overcoming limitations of prior established methods that quantify transfection efficiency. By using optimized ratios of transfection reagent and a nucleic acid (DNA or RNA) vector directly labeled with a fluorochrome, this method can be used as a tool to simultaneously quantify cellular toxicity of different transfection reagents, the amount of nucleic acid plasmid that cells have taken up during transfection as well as the amount of the encoded expressed protein. Finally, we demonstrate that this method is reproducible, can be standardized and can reliably and rapidly quantify transfection efficiency, reducing assay costs and increasing throughput while increasing data robustness.

Directed retrograde cerebral protection during moderate hypothermic circulatory arrest.

There are many choices for neurologic protection for aortic arch surgery. Although numerous investigators have challenged the efficacy of retrograde cerebral perfusion, we have had good results with our application of this technique. We performed a retrospective review of 8 consecutive patients who underwent surgery from 1 June 2001 through 31 March 2003; the age range was 33 to 97 years. All patients required circulatory arrest and underwent retrograde cerebral perfusion with use of a tourniquet on the patients' left and right arms above the elbow to direct retrograde flow to the brain. Moderate hypothermia (around 24 degrees C nasopharyngeal) was used; circulatory arrest time ranged from 27 to 63 minutes. There was 1 late hospital death due to multiple-organ system failure. There were no neurologic complications (stroke or temporary neurologic dysfunction). There was no substantive neurologic or renal dysfunction in this cohort, in which moderate hypothermia was used. These results are comparable to those reported in the literature for similar patients. We conclude that, for patients who require circulatory arrest, directed retrograde cerebral perfusion at moderate nasopharyngeal hypothermia gives results comparable to those reported with other techniques.