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Denosumab is a monoclonal anti-RANKL antibody that inhibits bone resorption, increases bone mass, and reduces fracture risk. Denosumab discontinuation causes an extensive wave of rebound resorption, but the cellular mechanisms remain poorly characterized. We utilized in situ hybridization (ISH) as a direct approach to identify the cells that activate osteoclastogenesis through the RANKL/OPG pathway. ISH was performed across species, skeletal sites, and following recombinant OPG (OPG:Fc) and parathyroid hormone 1-34 (PTH) treatment of mice. OPG:Fc treatment in mice induced an increased expression of RANKL mRNA mainly in trabecular, but not endocortical bone surface cells. Additionally, a decreased expression of OPG mRNA was detected in bone surface cells and osteocytes of both compartments. A similar but more pronounced effect on RANKL and OPG expression was seen one hour after PTH treatment. These findings suggest that bone surface cells and osteocytes conjointly regulate the activation of osteoclastogenesis, and that OPG:Fc treatment induces a local accumulation of osteoclastogenic activation sites, ready to recruit and activate osteoclasts upon treatment discontinuation. Analysis of publicly available single-cell RNA sequencing (scRNAseq) data from murine bone marrow stromal cells revealed that Tnfsf11 + cells expressed high levels of Mmp13, Limch1, and Wif1, confirming their osteoprogenitor status. ISH confirmed co-expression of Mmp13 and Tnfsf11 in bone surface cells of both vehicle- and OPG:Fc-treated mice. Under physiological conditions of human/mouse bone, RANKL is expressed mainly by osteoprogenitors proximate to the osteoclasts, while OPG is expressed mainly by osteocytes and bone-forming osteoblasts., (© 2024. The Author(s).)

Rebound bone loss following denosumab discontinuation is an important clinical challenge. Current treatment strategies to prevent this fail to suppress the rise and overshoot in osteoclast-mediated bone resorption. In this study, we use a murine model of denosumab treatment and discontinuation to show the temporal changes in osteoclast formation and activity during RANKL inhibition and withdrawal. We show that the cellular processes that drive the formation of osteoclasts and subsequent bone resorption following withdrawal of RANKL inhibition precede the rebound bone loss. Furthermore, a rise in serum TRAP and RANKL levels is detected before markers of bone turnover used in current clinical practice. These mechanistic advances may provide insight into a more defined window of opportunity to intervene with sequential therapy following denosumab discontinuation., (© The Author(s) 2024. Published by Oxford University Press on behalf of the American Society for Bone and Mineral Research.)

An imbalance between bone resorption and bone formation underlies the devastating osteolytic lesions and subsequent fractures seen in more than 90% of multiple myeloma (MM) patients. Currently, Wnt-targeted therapeutic agents that prevent soluble antagonists of the Wnt signaling pathway, sclerostin (SOST) and dickkopf-1 (DKK1), have been shown to prevent bone loss and improve bone strength in preclinical models of MM. In this study, we show increasing Wnt signaling via a novel anti-low-density lipoprotein receptor-related protein 6 (LRP6) antibody, which potentiates Wnt1-class ligand signaling through binding the Wnt receptor LRP6, prevented the development of myeloma-induced bone loss primarily through preventing bone resorption. When combined with an agent targeting the soluble Wnt antagonist DKK1, we showed more robust improvements in bone structure than anti-LRP6 treatment alone. Micro-computed tomography (μCT) analysis demonstrated substantial increases in trabecular bone volume in naïve mice given the anti-LRP6/DKK1 combination treatment strategy compared to control agents. Mice injected with 5TGM1eGFP murine myeloma cells had significant reductions in trabecular bone volume compared to naïve controls. The anti-LRP6/DKK1 combination strategy significantly improved bone volume in 5TGM1-bearing mice by 111%, which was also superior to anti-LRP6 single treatment; with similar bone structural changes observed within L 4 lumbar vertebrae. Consequently, this combination strategy significantly improved resistance to fracture in lumbar vertebrae in 5TGM1-bearing mice compared to their controls, providing greater protection against fracture compared to anti-LRP6 antibody alone. Interestingly, these improvements in bone volume were primarily due to reduced bone resorption, with significant reductions in osteoclast numbers and osteoclast surface per bone surface demonstrated in 5TGM1-bearing mice treated with the anti-LRP6/DKK1 combination strategy. Importantly, Wnt stimulation with either single or combined Wnt-targeted agents did not exacerbate tumor activity. This work provides a novel approach of targeting both membrane-bound and soluble Wnt pathway components to provide superior skeletal outcomes in patients with multiple myeloma and other bone destructive cancers. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR)., (© 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).)

To date, no discrete genetic signature has been defined for isolated Dclk1+ tuft cells within the small intestine. Furthermore, recent reports on the functional significance of Dclk1+ cells in the small intestine have been inconsistent. These cells have been proposed to be fully differentiated cells, reserve stem cells, and tumor stem cells. In order to elucidate the potential function of Dclk1+ cells, we FACS-sorted Dclk1+ cells from mouse small intestinal epithelium using transgenic mice expressing YFP under the control of the Dclk1 promoter (Dclk1-CreER;Rosa26-YFP). Analysis of sorted YFP+ cells demonstrated marked enrichment (~6000 fold) for Dclk1 mRNA compared with YFP- cells. Dclk1+ population display ~6 fold enrichment for the putative quiescent stem cell marker Bmi1. We observed significantly greater expression of pluripotency genes, pro-survival genes, and quiescence markers in the Dclk1+ population. A significant increase in self-renewal capability (14-fold) was observed in in vitro isolated Dclk1+ cells. The unique genetic report presented in this manuscript suggests that Dclk1+ cells may maintain quiescence, pluripotency, and metabolic activity for survival/longevity. Functionally, these reserve characteristics manifest in vitro, with Dclk1+ cells exhibiting greater ability to self-renew. These findings indicate that quiescent stem-like functionality is a feature of Dclk1-expressing tuft cells.

Purpose/objective: Our purpose was to examine congestive heart failure (CHF) readmissions from the veterans' perspective. The use of health care provider interventions, such as standardized education materials, home telehealth, and a CHF clinic, was able to reduce readmissions rates from 35% to 23%. Our objective was to use input from the veterans to fine-tune our efforts and achieve readmission rates for patients with CHF below the national average of 21%. We wanted to identify factors that result in CHF readmissions, including disease education, self-care management, and barriers to self-care. This study was directed toward answering two questions: 1. What is the veteran’s explanation for readmission? 2. According to the veteran, what are the barriers to following their treatment regimen?, Primary Practice Setting: It was a rural 84-bed Veterans Health Administration hospital in the Western United States., Findings: Before this study, our efforts to reduce CHF readmissions were one-sided, all from the health care professionals' viewpoint. We wanted to hear what the veteran had to say; so, we interviewed 25 veterans. Four veterans were excluded due to issues with their consents. Ninety percent (n = 19/21) responded that they knew their CHF was worse by a change in their breathing (shortness of breath). They identified 48 signs/symptoms that indicated worsening CHF. Weight gain was noted as an indication of worsening CHF symptoms (n = 6/48) in 12.5% of the responses. Twenty-five percent (n = 12/48) of the veterans stated they recognized the early symptoms of worsening CHF. Thirty-eight percent (n = 8/21) of the veterans stated they had early symptoms of worsening CHF, but only two of them contacted their doctor. It is interesting to note that only 29% (n = 6/21) of the veterans recognized weight gain as a sign of worsening CHF and all of these veterans listed other symptoms (such as shortness of breath) along with weight gain. Weighing on a daily basis was practiced by only 30% of the group (n = 7/21); all but two of the veterans had no problems with weighing themselves. More than 71% of the veterans responded that they had no problems following their diet or taking their medications. More than half of the veterans did not need help with meals, transportation, or daily grooming/dressing/toileting., Conclusions: We were concerned about the evident delays in seeking medical care for worsening CHF. All veterans who did need help with the activities of daily living, medications, or diet had their needs met through their support systems. They did not perceive any barriers to seeking care. However, there remain many unanswered questions. Does the patient understand their discharge education and know how to use this information from daily weights or recognition of early symptoms, to indicate their need for urgent and emergency medical interventions? Or is it a problem that the education is not sufficient? Is it a question of the burden of care from multiple comorbid conditions or of taking too many medications? Do social issues drive readmissions? These questions are further explored in a second study, which is in the data analysis stage., Implications for Case Management Practice: There are three key findings from our study. 1. Veterans think in terms of symptoms that increase the impact of CHF on their life. 2. The relationship between daily weight and controlling CHF is not clear to veterans. 3. Hospital discharge instructions should clearly associate symptoms that are associated with worsening CHF.

The major groups of enzymes involved in activating and detoxifying therapeutic drugs, not least several anti-cancer drugs, include the cytochromes P450 (P450s), epoxide hydrolase, and glutathione S-transferases (GSTs). The expression of these enzymes in malignant tumours is one possible mechanism of anti-cancer drug resistance. This study has investigated the presence, cellular localization, and distribution of drug-metabolizing enzymes in prostate cancer. The P450 subfamilies CYP1A, CYP2C, and CYP3A were present in 63, 25, and 61 per cent of tumours, respectively. Epoxide hydrolase was identified in 96 per cent of tumours. GST-alpha and GST-mu were expressed in 29 and 41 per cent of tumours, respectively, while there was no immunoreactivity for the pi form of GST. The absence of GST-pi in prostate cancer contrasts with the frequent expression of GST-pi observed in other types of malignant tumour. In non-neoplastic prostatic epithelium, there was expression of CYP1A, CYP2C, epoxide hydrolase, and the different forms of GST, while there was no apparent immunoreactivity for CYP3A.

The cytochromes P450, epoxide hydrolase and glutathione S-transferases are several of the major groups of enzymes involved in the metabolism of xenobiotics and these enzymes may have a role in influencing the response of tumours to anti-cancer drugs. In this study the cell specific expression of individual xenobiotic metabolizing enzymes has been investigated using immunohistochemistry in primary transitional cell tumours of the urinary bladder. The cytochromes P450 CYP1A, CYP2C and CYP3A, were present in 68, 28 and 68% of tumours respectively and the expression of CYP1A correlated with bladder tumour grade (P = 0.03). Epoxide hydrolase was identified in 84% of tumours while the alpha, mu and pi forms of glutathione S-transferase were expressed in 56, 72 and 52% of tumours respectively. In normal bladder epoxide hydrolase and glutathione S-transferase pi were the main enzymes expressed while there was no expression of CYP2C.

Several lines of evidence suggest that the anticonvulsant drug valproate may have antipanic properties: (1) It enhances gamma-aminobutyric acid activity in the brain; (2) it has anxiolytic effects in animal models of anxiety; and (3) it has been reported to be effective in panic disorder in several preliminary studies; however, valproate has not been studied in the prevention of lactate-induced panic attacks. Sixteen patients with panic disorder underwent a lactate infusion followed by a 28-day treatment period with valproate and subsequent rechallenge with lactate. Response was measured by change in panic attack frequency and Hamilton Anxiety Scale (HAS) scores and by the ability of valproate to block lactate-induced panic on rechallenge. Of the 14 patients completing the 28-day trial, 10 (71%) experienced a greater than 50% reduction in the weekly frequency of panic attacks. Six (43%) had complete remission. HAS scores dropped significantly from a baseline mean of 30.8 +/- 9.4 (SD) to 12.6 +/- 7 after 4 weeks of treatment. Valproate blocked reinduction of panic symptoms on lactate rechallenge in 10 (83%) of 12 patients who had initially experienced panic symptoms on initial infusion. The significant reduction in spontaneous panic attacks and the blockade of lactate-induced panic symptoms by valproate support earlier studies suggesting that the drug may be an effective treatment for panic disorder.

We have synthesized pulmonary surfactant apoprotein SP-B peptides by solid-phase chemistry and demonstrated their ability to enhance the surface-active properties of synthetic lipid mixtures. The synthetic peptides were reactive with antiserum generated against the native bovine surfactant peptide. Both peptides conferred surfactant-like properties to synthetic lipid mixtures as assessed by a Wilhelmy balance and pulsating bubble surfactometer. Likewise, mixtures of synthetic SP-B peptides and lipid restored compliance of isolated surfactant-deficient rat lungs. This work demonstrates the utility of SP-B as a functional component of pulmonary surfactant mixtures for treatment of respiratory distress syndrome or other disorders characterized by surfactant deficiency.

A radiolucency in the cervical spine consistently seen on panoramic dental radiographs has been investigated. It was found to arise from the axis and be caused by a combination of its unique morphology and the oblique angle of incidence of the X-ray beam in the first part of its rotation.

Methodology for the quantitative determination of clorazepate dipotassium and monopotassium in solid dosage forms was developed. Clorazepate was resolved from its degradation products, making the analysis specific and stability indicating. Analytical separation was performed on a octadecylsilylated silica column. Clorazepate was extracted from the dosage forms with 0.04% NaOH and chromatographed with aqueous 0.005 M tetra-n-butylammonium ion (pH 7.5)- acetonitrile (70:30) as the eluent. The analysis was completed in approximately 20 min with a precision of less than 2.4% RSD.

Seventy severely retarded adults were taught a vocational assembly-skill task involving a difficult visual--motor discrimination. Comparisons of relative effects on trials-to-criterion were made among two types of verbal-correction procedures (general: "try another way" and specific: "flat side in") and three types of systematic physical-correction procedures (gesture, physical prompt, and repeated practice). Reliable differences in effects occurred only between the three systematic physical-correction procedures, with repeated practice the most effective, physical prompts next, and gestures the least effective. The results were interpreted as demonstrating the efficacy of trainer-related training procedures in relation to stimulus-related strategies, as well as relative efficacy among trainer-related correction procedures.

The Trainee Performance Sample, a vocational skills assessment instrument, was revised to enhance content validity and utility in making vocational skill learning placements for severely retarded individuals. The Trainee Performance Sample employs a process measurement approach; i.e., each of the 30 test items (a variety of benchwork tasks) includes both training and correction procedures within the item. To some extent, the examinee's ability to benefit from various training strategies is measured. Psychometric analyses demonstrated that the revised Trainee Performance Sample meets standard test development criteria. Thus, a dynamic approach to vocational skills assessment of severely retarded individuals--one that involves training while testing--has been shown to have both utility and psychometric adequacy.

The literature relating to oral manifestations of Crohn's disease is reviewed and a case is reported in which clinical and histopathologic features of oral Crohn's disease are present without demonstrable gastrointestinal lesions. It is suggested that it is reasonable to make a firm diagnosis of the condition on this evidence alone and to monitor the patient for subsequent gastrointestinal symptoms, so that treatment can be instituted at an early stage.