Impact of body mass index on outcomes in patients undergoing percutaneous coronary intervention for in-stent restenosis

Background

Recent advances in drug eluting stents (DES) design have significantly decreased the rates of in-stent restenosis (ISR). Nonetheless, ISR remains a major problem, affecting 5–10% of patients undergoing percutaneous coronary intervention (PCI). Furthermore, PCI for ISR is often a poor prognostic factor for outcomes after the procedure. Historically, obese patients tended to have better outcomes when undergoing PCI, however it is unclear if this trend continues for the same population undergoing PCI for ISR.

Purpose

Investigate the outcomes of patients undergoing PCI for ISR in the overweight and normal weight population.

Methods

All patients undergoing PCI with DES implantation at a tertiary care center from January 2012 to December 2019 were included. Normal weight was defined as a body mass index (BMI) greater than or equal to 18.5 kg/m2 and less than 25 kg/m2, while overweight was defined as a BMI greater than or equal to 25 kg/m2. Patients with BMI <18.5 kg/m2, underwent PCI for acute myocardial infarction (MI), or received a bare metal stent (BMS) were excluded. The primary outcome was major events (MACE), a composite of all-cause mortality, myocardial infarction (MI), and target vessel revascularization (TVR) up to one year after PCI. Secondary outcomes included individual components of the primary endpoint.

Results

Out of 16,234 patients with available data on BMI, 12,444 (76.7%) were overweight and 3,790 (23.3%) were normal weight. Among overweight patients, 2,879 (23.1%) underwent PCI for ISR versus 815 (21.5%) of normal weight patients. Regardless of BMI status, patients undergoing PCI for ISR had higher rates of co-morbidities such as hypertension, hyperlipidemia, and diabetes mellitus than non-ISR counterparts. At one year post PCI, both overweight and normal weight patients undergoing PCI for ISR had increased risk of MACE (overweight: 18.4% vs. 6.7%; HR 2.83; 95% CI 2.50–3.20; normal weight: 18.8% vs. 7.8%, HR 2.43, 95% CI 1.95–3.04) when compared to non-ISR counterparts, mostly driven by TVR (overweight: 16% vs. 4.6%; HR 3.58; 95% CI 3.11–4.13; normal weight: 15.2% vs. 4.1%; HR 3.69; 95% CI 2.80–4.86). However, only overweight patients undergoing PCI for ISR had higher risk of all cause mortality (2.2% vs. 1.5%; HR 1.42; 95% CI 1.03–1.95) and MI (3.0% vs. 1.3%, HR 2.22; 95% CI 1.64–2.99) when compared to non-ISR counterparts (Figure 1).

Conclusions

PCI for ISR was associated with increased risk of MACE, irrespective of body weight. The risks of all-cause mortality and MI in ISR vs non-ISR patients only reached statistical significance in overweight patients.

Funding Acknowledgement

Type of funding sources: None.

Office based inferior turbinate coblation treatment: a randomized controlled trial on effectiveness and tolerability of medicinal honey

Background: When conservative treatment for nasal obstruction fails, surgery is often applied. Inferior Turbinate Hypertrophy (ITH) is a common cause of nasal obstruction, which can be treated by means of radiofrequency coblation. This technique can be administered under local anesthesia (office based coblation; OBC) and if expedient combined with a lateralization (out-fracture) of the inferior turbinate (IT). Ointment based on medical grade honey, is known to have wound healing characteristics. Methodology: Single center, single blinded randomized controlled trial. Fifty-five subjects received bilateral OBC of the IT. Subjects were randomized to postoperative care with either nasal saline irrigations (NSI) or NSI combined with ointment based on honey (NSI+STB). Subjects weekly reported subjectively overall nasal burden, -crusting, -pain, loss of smell by means of VAS-scores and nasal obstruction by means of the NL-NOSE scale. Results: No significant differences between the NSI and NSI+STB groups, though the latter showed less pain. Concerning the study group as a whole, mean nasal burden score and nasal obstruction significantly decreased from 63.4 to 16.0 and 65.3 to 22.0, respectively. Nasal crusting, -pain, and loss of smell largely resolved 3-4 weeks postoperatively and were only mild. Concomitant lateralization showed a tendency to quicker resolution of the nasal obstruction. Conclusions: OBC is a safe, well tolerated and effective treatment for nasal obstruction caused by ITH. Concerning multiple end-points, we found no evidence of a beneficial effect of ointment based on honey as addition to NSI in postoperative care, except a clear tendency in less crusting and pain.

Differential trafficking of transforming growth factor-beta receptors and ligand in polarized epithelial cells

Epithelial cells in vivo form tight cell-cell associations that spatially separate distinct apical and basolateral domains. These domains provide discrete cellular processes essential for proper tissue and organ development. Using confocal imaging and selective plasma membrane domain activation, the type I and type II transforming growth factor-beta (TGFbeta) receptors were found to be localized specifically at the basolateral surfaces of polarized Madin-Darby canine kidney (MDCK) cells. Receptors concentrated predominantly at the lateral sites of cell-cell contact, adjacent to the gap junctional complex. Cytoplasmic domain truncations for each receptor resulted in the loss of specific lateral domain targeting and dispersion to both the apical and basal domains. Whereas receptors concentrate basolaterally in regions of direct cell-cell contact in nonpolarized MDCK cell monolayers, receptor staining was absent from areas of noncell contact. In contrast to the defined basolateral polarity observed for the TGFbeta receptor complex, TGFbeta ligand secretion was found to be from the apical surfaces. Confocal imaging of MDCK cells with an antibody to TGFbeta1 confirmed a predominant apical localization, with a stark absence at the basal membrane. These findings indicate that cell adhesion regulates the localization of TGFbeta receptors in polarized epithelial cultures and that the response to TGFbeta is dependent upon the spatial distribution and secretion of TGFbeta receptors and ligand, respectively.

Transforming growth factor beta receptor signaling and endocytosis are linked through a COOH terminal activation motif in the type I receptor

Transforming growth factor beta (TGF-beta) coordinates a number of biological events important in normal and pathophysiological growth. In this study, deletion and substitution mutations were used to identify receptor motifs modulating TGF-beta receptor activity. Initial experiments indicated that a COOH-terminal sequence between amino acids 482-491 in the kinase domain of the type I receptor was required for ligand-induced receptor signaling and down-regulation. These 10 amino acids are highly conserved in mammalian, Xenopus, and Drosophila type I receptors. Although mutation or deletion of the region (referred to as the NANDOR BOX, for nonactivating non-down-regulating) abolishes TGF-beta-dependent mitogenesis, transcriptional activity, type I receptor phosphorylation, and down-regulation in mesenchymal cultures, adjacent mutations also within the kinase domain are without effect. Moreover, a kinase-defective type I receptor can functionally complement a mutant BOX expressing type I receptor, documenting that when the BOX mutant is activated, it has kinase activity. These results indicate that the sequence between 482 and 491 in the type I receptor provides a critical function regulating activation of the TGF-beta receptor complex.

Mechanisms of transforming growth factor-beta receptor endocytosis and intracellular sorting differ between fibroblasts and epithelial cells

Transforming growth factor-betas (TGF-beta) are multifunctional proteins capable of either stimulating or inhibiting mitosis, depending on the cell type. These diverse cellular responses are caused by stimulating a single receptor complex composed of type I and type II receptors. Using a chimeric receptor model where the granulocyte/monocyte colony-stimulating factor receptor ligand binding domains are fused to the transmembrane and cytoplasmic signaling domains of the TGF-beta type I and II receptors, we wished to describe the role(s) of specific amino acid residues in regulating ligand-mediated endocytosis and signaling in fibroblasts and epithelial cells. Specific point mutations were introduced at Y182, T200, and Y249 of the type I receptor and K277 and P525 of the type II receptor. Mutation of either Y182 or Y249, residues within two putative consensus tyrosine-based internalization motifs, had no effect on endocytosis or signaling. This is in contrast to mutation of T200 to valine, which resulted in ablation of signaling in both cell types, while only abolishing receptor down-regulation in fibroblasts. Moreover, in the absence of ligand, both fibroblasts and epithelial cells constitutively internalize and recycle the TGF-beta receptor complex back to the plasma membrane. The data indicate fundamental differences between mesenchymal and epithelial cells in endocytic sorting and suggest that ligand binding diverts heteromeric receptors from the default recycling pool to a pathway mediating receptor down-regulation and signaling.

Heteromeric and homomeric transforming growth factor-beta receptors show distinct signaling and endocytic responses in epithelial cells

Transforming growth factor-beta (TGF-beta) induces distinct responses dependent upon the cellular context. It is unclear whether the initial receptor interactions identified in one cell type will be operative in another. Utilizing a chimeric receptor strategy we have examined the signaling and endocytic activity of both heteromeric (type I/type II) and homomeric (type I/type I or type II/type II) TGF-betaR interactions in Mv1Lu epithelial cells. In agreement with that observed in mesenchymal cells, all TGF-betaR signaling in Mv1Lu cells required the formation of a heteromeric type I-type II receptor complex. However, the initial endocytic response to TGF-betaR oligomerization was distinctly regulated in the two cell types. While heteromeric TGF-beta receptors were internalized and down-regulated, homomeric TGF-betaR interactions showed diminished endocytic activity in Mv1Lu cells. This contrasts to that observed in mesenchymal cultures where ligand bound to TGF-betaR homomers was internalized, yet the receptors were not down-regulated. Moreover, while previous reports have suggested that mutations at serine 172 or threonine 176 in the type I TGF-betaR separated transcriptional from proliferative responses, we found no separation of pathways or effect on initial endocytic activity when the analogous mutations were made in the chimeric receptors.

Pneumocystis carinii inhibits cyclin-dependent kinase activity in lung epithelial cells

Pneumocystis carinii remains an important cause of pneumonia in patients with AIDS. Attachment of the organism to epithelial cells is a central event in establishing infection, impairing the growth potential of lung epithelial cells and thereby slowing repair. In light of investigations documenting a central role for cyclin-dependent kinases in controlling the cell cycle, we addressed the hypothesis that P. carinii inhibits epithelial cell growth by interfering with host epithelial cyclin-dependent kinase (cdk) activity. We observed that P. carinii significantly impaired growth of cultured mink lung epithelial cells, with effects observed after 48-72 h of treatment. However, the kinase activity associated with p34cdc2 or p33cdk2 was maximally inhibited as early as 24 h after P. carinii exposure. The inhibitory effect on cyclin-dependent kinase activity was mediated by the trophozoite form of P. carinii, in that highly purified trophozoites exerted marked inhibition of p34cdc2 activity. Growth impairment was similarly preceded by P. carinii-induced alteration in the state of epithelial cell p34cdc2 phosphorylation, with no change in p34cdc2 or p33cdk2 protein levels. These data strongly suggest that the antiproliferative activity of P. carinii on respiratory epithelium is mediated in part through modulation of the host cell cycle machinery.

[Incidence and prevalence of genetically-determined disorders in The Netherlands; a literature study]

OBJECTIVE

To analyse if data now available on frequencies of genetic disorders are sufficient to be used in future as indicators when an evaluation of new developments is desired for policy-making purposes.

DESIGN

Literature study.

SETTING

The Netherlands.

METHOD

Using automated literature search systems, papers published before October 1991 were surveyed and an inventory of incidence and prevalence of genetic disorders in the Netherlands was made.

RESULTS

Depending on the pattern of heredity differences in available data and their validity were found. Valid data on most of the II congenital anomalies investigated were available from the EUROCAT registration in the northern Netherlands. This method of data collecting is also suitable for the evaluation of prevalence development. On the 29 multifactorial diseases occurring later in life that were investigated many data were available, although the varying sources made comparison difficult. These data were often out of date and had a highly varying validity. Of 3 chromosomal abnormalities the prevalence at birth was known. Of only 22 out of 650 monogenic disorders, described in the Netherlands up to 1991, the prevalence at birth and(or) in the population was known.

CONCLUSION

Data on frequency of genetic disorders can be collected but the information now available is insufficient to serve as an indicator for government policy. Frequencies should also be considered in relation to the impact of the disease on the individual, his environment and society.

Ability of normal human keratinocytes that grow in culture in serum-free medium to be derived from suprabasal cells

The current studies were performed to determine from which regions of the skin keratinocytes that grow in vitro are derived. Normal human foreskin specimens were first separated by differential trypsinization into two suprabasal fractions and one basal fraction. Utilizing complete MCDB 153 basal nutrient culture medium containing epidermal growth factor and insulin, we then evaluated the clonogenic potential of cells in these three fractions. Suprabasal cell fractions demonstrated a colony-forming efficiency as great as or greater than that of the basal cell fraction, and 10%-15% of the keratinocytes that grew in primary and secondary cultures expressed involucrin, a suprabasal keratinocyte differentiation marker. Of such involucrin-containing keratinocytes, 80% also possessed the potential to undergo DNA synthesis, as determined by autoradiography following a 48-hour incubation with [3H]thymidine. These observations support the conclusion that the human keratinocytes that grow in vitro in serum-free medium can be derived from suprabasal cells and, therefore, that a state of nonterminal keratinocyte differentiation exists.