Communication between Mast Cells and Group 2 Innate Lymphoid Cells in the Skin

The skin is a dynamic organ with a complex immune network critical for maintaining balance and defending against various pathogens. Different types of cells in the skin, such as mast cells (MCs) and group 2 innate lymphoid cells (ILC2s), contribute to immune regulation and play essential roles in the early immune response to various triggers, including allergens. It is beneficial to dissect cell-to-cell interactions in the skin to elucidate the mechanisms underlying skin immunity. The current manuscript concentrates explicitly on the communication pathways between MCs and ILC2s in the skin, highlighting their ability to regulate immune responses, inflammation, and tissue repair. Furthermore, it discusses how the interactions between MCs and ILC2s play a crucial role in various skin conditions, such as autoimmune diseases, dermatological disorders, and allergic reactions. Understanding the complex interactions between MCs and ILC2s in different skin conditions is crucial to developing targeted treatments for related disorders. The discovery of shared pathways could pave the way for novel therapeutic interventions to restore immunological balance in diseased skin tissues.

Murine Mast Cells That Are Deficient in IFNAR-Signaling Respond to Viral Infection by Producing a Large Amount of Inflammatory Cytokines, a Low Level of Reactive Oxygen Species, and a High Rate of Cell Death

Mat cells (MCs) are located in the skin and mucous membranes at points where the body meets the environment. When activated, MCs release inflammatory cytokines, which help the immune system to fight viruses. MCs produce, and have receptors for interferons (IFNs), which belong to a family of cytokines recognized for their antiviral properties. Previously, we reported that MCs produced proinflammatory cytokines in response to a recombinant vesicular stomatitis virus (rVSVΔm51) and that IFNAR signaling was required to down-modulate these responses. Here, we have demonstrated that UV-irradiated rVSVΔm51 did not cause any inflammatory cytokines in either in vitro cultured mouse IFNAR-intact (IFNAR+/+), or in IFNAR-knockout (IFNAR-/-) MCs. However, the non-irradiated virus was able to replicate more effectively in IFNAR-/- MCs and produced a higher level of inflammatory cytokines compared with the IFNAR+/+ MCs. Interestingly, MCs lacking IFNAR expression displayed reduced levels of reactive oxygen species (ROS) compared with IFNAR+/+ MCs. Additionally, upon the viral infection, these IFNAR-/- MCs were found to coexist with many dying cells within the cell population. Based on our findings, IFNAR-intact MCs exhibit a lower rate of rVSVΔm51 infectivity and lower levels of cytokines while demonstrating higher levels of ROS. This suggests that MCs with intact IFNAR signaling may survive viral infections by producing cell-protective ROS mechanisms and are less likely to die than IFNAR-/- cells.

Vitamin D Influences the Activity of Mast Cells in Allergic Manifestations and Potentiates Their Effector Functions against Pathogens

Mast cells (MCs) are abundant at sites exposed to the external environment and pathogens. Local activation of these cells, either directly via pathogen recognition or indirectly via interaction with other activated immune cells and results in the release of pre-stored mediators in MC granules. The release of these pre-stored mediators helps to enhance pathogen clearance. While MCs are well known for their protective role against parasites, there is also significant evidence in the literature demonstrating their ability to respond to viral, bacterial, and fungal infections. Vitamin D is a fat-soluble vitamin and hormone that plays a vital role in regulating calcium and phosphorus metabolism to maintain skeletal homeostasis. Emerging evidence suggests that vitamin D also has immunomodulatory properties on both the innate and adaptive immune systems, making it a critical regulator of immune homeostasis. Vitamin D binds to its receptor, called the vitamin D receptor (VDR), which is present in almost all immune system cells. The literature suggests that a vitamin D deficiency can activate MCs, and vitamin D is necessary for MC stabilization. This manuscript explores the potential of vitamin D to regulate MC activity and combat pathogens, with a focus on its ability to fight viruses.

Study of Structural stability and formation mechanisms in DSPC and DPSM liposomes: A coarse-grained molecular dynamics simulation

Liposomes or biological vesicles can be created from cholesterol, phospholipid, and water. Their stability is affected by their phospholipid composition which can influence disease treatment and drug delivery efficacy. In this study, the effect of phospholipid type on the formation and stability of liposomes using coarse-grained molecular dynamics simulations is investigated. For this purpose, the simulation study of the DSPC (1,2-distearoyl-sn-glycero-3-phosphocholine) and DPSM (Egg sphingomyelin) lipids were considered. All simulations were carried out using the Gromacs software and Martini force field 2.2. Energy minimization (3000 steps) model, equilibrium at constant volume to adjust the temperature at 400 Kelvin and equilibrium at constant pressure to adjust the pressure, at atmospheric pressure (1 bar) have been validated. Microsecond simulations, as well as formation analysis including density, radial distribution function, and solvent accessible surface area, demonstrated spherical nanodisc structures for the DPSM and DSPC liposomes. The results revealed that due to the cylindrical geometric structure and small-size head group, the DSPC lipid maintained its perfectly spherical structure. However, the DPSM lipid showed a conical geometric structure with larger head group than other lipids, which allows the liposome to form a micelle structure. Although the DSPC and DPSM lipids used in the laboratory tests exhibit liposome and micelle behaviors, the simulation results revealed their nanodisc structures. Energy analysis including overall energy, Van der Waals interaction energy, and electrostatic interaction energy showed that DPSM liposome is more stable than DSPC liposome.

Pathological evaluation of differentiated thyroid cancer in patients with positive serum thyroglobulin and negative iodine scan

OBJECTIVE

There is no investigation that emphasizes the pathology of DTC (differentiated thyroid cancer) patients with positive Tg and negative iodine scan. The present study was performed to assess the pathology of these patients.

MATERIALS AND METHODS

In this retrospective study, the records of 500 patients with differentiated thyroid cancer between June 2005 and November 2011 were assessed, and those patients who had elevated serum thyroglobulin (Tg) with a negative whole body I-131 scan (Tg+/WBS-) were included in the study. Patients were followed for clinical and pathological findings of thyroid cancer, including type, variant, local invasion and cervical lymph node metastasis, and serum Tg, TgAb, and TSH levels.

RESULTS

A total of 38 patients, including 31 (81.6%) females and 7 (18.4) males with a mean age of 44.2 ± 15.6 years (range, 14 to 77 yrs) took part in the study. All 38 patients had the papillary type of differentiated thyroid cancer (PCDTC), and none had the follicular type of differentiated thyroid cancer (FCDTC). For the variant type of PTC in 16 patients, it was found that 7 were classic type (43.8%), 7 were follicular type (43.8%), and 2 were tall cell (12.4%) for papillary thyroid cancer. In 22 patients no distinct variant had been reported.

CONCLUSIONS

This report demonstrated that all of the 38 patients were PTC (100%), which is different from other previous studies. It may be concluded that the overall pathologic subtypes changes of DTC could mainly be due to the iodine fortification program in various geographic regions. The relationship between DTC pathologic subtypes and frequency of Tg+/WBS- condition was difficult to assess in this work. Therefore, further studies are required to evaluate this issue.

Management of gastrointestinal complaints in differentiated thyroid cancer patients treated with (131)I: comparison of the efficacy of pantoprazole, metoclopramide, and ondansetron - a randomized clinical trial

OBJECTIVE

To compare safety and efficacy of pantoprazol , metoclopramide, ondansetron, as compared to placebo, in controlling gastrointestinal (GI) complaints of thyroid cancer patients treated with I-131these patients.

DESIGN

Four-armed, parallel group, single blind, randomized controlled clinical trial, setting: A university hospital, registration: database for clinical trials IRCT2013061713705N1.

PATIENTS

85 patients with differentiated thyroid cancer who received 131I.

MAIN OUTCOME MEASURES

Postradioiodine nausea and vomiting within three days of therapy (primary endpoint); occurrence of adverse reaction.

RESULTS

The patients' characteristics were similar within the study groups. Among the study variables, age, sex, administered dosage, history of previous GI complaints, and history of hyperemesis gravidarum in female patients were not statistically different among the groups (p > 0.05). The results revealed that only ondansetron shows a therapeutic benefit over the placebo in controlling nausea (p < 0.05); however, it does not prevent vomiting (p > 0.05). The other two drugs, pantoprazole and metoclopramide, did not control nausea (p > 0.05) or vomiting (p > 0.05).

CONCLUSIONS

This study may demonstrate that the therapeutic dose of ondansetron could be an effective prophylactic agent in controlling GI complaints in differential thyroid carcinoma (DTC) patients following RAI therapy; however, these preliminary findings should be validated in larger studies.

Association between health-related quality of life and impaired glucose metabolism in Iran: the Qazvin Metabolic Diseases Study

AIM

To evaluate the association between health-related quality of life and glucose metabolism status in a study population in Qazvin, Iran.

METHODS

This cross-sectional study was conducted in 1044 people (aged 20-78 years old) between September 2010 and April 2011 in Qazvin, Iran. An oral glucose tolerance test was performed for each participant who had never been diagnosed with diabetes. Participants were characterized as having normal glucose metabolism, pre-diabetes or diabetes according to American Diabetes Association criteria. The short-form 36 questionnaire was used to measure quality of life. Data were analysed using a chi-squared test, anova and ancova.

RESULTS

A total of 530 (51.7%) of the participants were women, and 24.1 and 11.6% of the participants were categorized as having prediabetes and diabetes mellitus, respectively. Except for the role emotional domain, there was a gradual decrease in the mean scores of every domain of the short-form 36 scale across the three study groups. The mean scores in the physical domains were significantly different among the participants with normal glucose metabolism and those with diabetes. After adding age as covariate, there were no significant differences between the categories in any of the domains.

CONCLUSION

There is no association between quality of life domains and glucose metabolism status in Iranian subjects. More longitudinal studies are necessary to investigate the natural history of pre-diabetes, diabetes and quality of life.

The role of cognitive group therapy and happiness training on cerebral blood flow using 99mTc-ECD brain perfusion SPECT: a quasi-experimental study of depressed patients

OBJECTIVE

The purpose of this study is to investigate the impact of cognitive group therapy and happiness training objectively in the local cerebral blood flow of patients with major depression (MD).

PATIENTS, MATERIAL, METHODS

The present research is semi-experimental to pre- and post-test with a control group. Three groups were formed, and this number was incorporated in each group: 12 patients were chosen randomly; the first group of depressed patients benefited from the combination of pharmacotherapy and sessions of cognitive group therapy; the second group used a combination of pharmacotherapy and sessions of happiness training; and a third group used only pharmacotherapy. We compared cognitive-behavioural therapy and happiness training efficacy with only pharmacotherapy in MD patients. We performed brain perfusion SPECT in each group, before and after each trial.

RESULTS

The study was conducted on 36 patients with MD (32 women and 4 men; mean age: 41.22 ± 9.08; range: 27-65 years). There were significant differences regarding the two trial effects into two experimental groups (p < 0/001) before and after trials, while such differences were not significant in the control group (p > 0.05). In addition, there was significant difference among the regional cerebral blood flow in the frontal and prefrontal regions into two experimental groups before and after trials (p < 0/001), while such differences were not significant in the control group (p > 0.05).

CONCLUSION

This study demonstrated decreased cerebral perfusion in the frontal regions in MD patients, which increased following cognitive group therapy and happiness training. Because of its availability, low costs, easy performance, and the objective semi-quantitative information supplied, brain perfusion SPECT scanning might be useful to assess the diagnosis and therapy efficacy. Further exploration is needed to validate its clinical role.

Clinical significance of mild inferolateral wall ischemia of the left ventricle on 99mTc-MIBI myocardial perfusion single photon emission computed tomography (SPECT)

INTRODUCTION

Mild ischemia in the inferolateral wall on myocardial perfusion imaging is seen frequently in practice. The aim of this study is to assess the importance of the above issue on myocardial perfusion SPECT with coronary angiography.

PATIENTS AND METHODS

All patients enrolled in this study exhibited mild ischemia of the inferolateral wall on myocardial single photon emission computed tomography (SPECT) with 99mTc-MIBI, using the 20 left ventricular segments model. Each patient completed a questionnaire, including type of chest pain, risk factors, and previous examinations, and all cases were followed up for one year. Luminal stenosis of >50% was classified as significant stenosis on coronary angiography. A p value < 0.05 was considered statistically significant.

RESULTS

During investigation, 105 cases had mild ischemia on myocardial perfusion imaging (MPI) of which 36 subjects (22 male and 14 female) underwent coronary angiography. The mean age was 56.62±10.23 years old (age range: 36-73 years). The inferolateral wall was compared to the left circumflex (LCX) territory. Nineteen out of 36 (52.7%) cases had stenosis in the LCX. Twenty-three of 105 (21.90%) underwent revascularization during the one year follow up. In multiple logistic regressions, with LCX stenosis on angiography as the dependent variable, only abnormal MPI was independently associated significantly.

CONCLUSIONS

The findings of the study may indicate that even a mild perfusion defect in the inferolateral wall should be carefully managed, especially in high-risk subjects for coronary artery disease.

The utility and prognostic value of dipyridamole technetium-99m sestamibi myocardial perfusion imaging SPECT in predicting perioperative cardiac events following non-cardiac surgery

OBJECTIVE

A perioperative cardiac events is one of the most important medical concerns for both surgeons and patients. The purpose of the current study was to determine the prognostic value of myocardial perfusion imaging (MPI), using dipyridamole 99m Tc-MIBI, for the prediction of perioperative cardiac events.

MATERIALS AND METHODS

This study included 253 patients who were candidates for non-cardiac elective surgery and underwent scanning with dipyridamole 99m Tc-MIBI. Based on normal or abnormal MPI, patients were divided into two groups and all preoperative cardiac events were recorded. Risk factors, including diabetes mellitus, dyslipidemia, hypertension, smoking and age ≥70 years, were compared between patients with normal and abnormal MPI and, also, in patients with or without cardiac events.

RESULTS

There were 197 patients with normal and 56 patients with abnormal MPI. In total, 14 patients had perioperative cardiac events, which included myocardial infarction (MI), hypotension, arrhythmia and death; of the 14 patients with perioperative cardiac events, 12 had abnormal and two had normal MPI. There were statistically meaningful differences between the two groups (p<0.001). Based on these findings, we determined that MPI had a sensitivity of 85.7%, a specificity of 81.6%, an accuracy of 81.8%, a positive predictive value of 21.4 % and a negative predictive value of 98.9%.

CONCLUSION

The incidence of perioperative cardiac events is higher in patients with abnormal MPI. Dipyridamole 99m Tc-MIBI myocardial perfusion imaging can accurately detect the preoperative cardiac risk of patients undergoing major non-cardiac surgery. Based on these findings, the occurrence of perioperative cardiac events in patients with abnormal MPI should be considered, especially in the older age population (age ≥70).

Comparison of three with six regions of interest analyses in patients with idiopathic constipation undertaking colon transit scintigraphy using 67Ga-citrate

OBJECTIVE AND INTRODUCTION: Preparation of data from 6 geometric regions of interest in the colon is time consuming, and can become impractical in the environment of busy Nuclear Medicine Departments. Therefore, we have investigated and demonstrated an alternative method for obtaining the same diagnostic information from an analysis of patients with idiopathic constipation who underwent colon transit scintigraphy using 67Ga-citrate. Data analysis methods using three regions of interest are compared to the results obtained using the more time consuming 6 regions of interest method to analyze the data.

MATERIALS AND METHODS

In this study, we report our results of the comparative reanalysis of data obtained by more traditional methods. We compare 3 regions of interest (ROI) which were taken from areas including the right colon, left colon and the rectosigmoid colon, with original work using our alternative 6 (ROI) diagnostic methodology. In addition, the proximal colonic emptying (PCE) was determined at 24 hr post ingestion among members of 3 identified subject groups.

RESULTS

The distribution of activity as the ingested 67Ga-citrate passes through the colon constitutes an activity profile. The mean activity position in the colon can be determined from subsequent radiographic images and from this the mean clearance time can be calculated.  In quantitative assessment, this represents the time at which half of activity was eliminated from colon (mean half clearance time - MCT) which did not appear different in the reanalysis. There is no significant difference in the current study in GMC 24h, GMC 48h and GMC 72h between two groups using the Man Whitney u test (p > 0.05), while in the previous work the results were statistically significant for the two later time periods GMC (GMC 48h and GMC 72h) (p = 0.016 and p = 0.027 respectively). The PCE in the group 1 was = 2.50 (0.37); group 2, 1.57 (0.47) and group 3, 2.97. The PCE was not different between the two groups (p = 0.21).

CONCLUSIONS

This investigation demonstrated that the radionuclide colon transit study using 67Ga-citrate is a safe, physiologic, and quantitative method for evaluating the transit of fecal material from cecum to rectum. Although, the visual assessment of diagnosis of the subjects in the two analyses is the same, it was not completely supported by quantitative measurements. Therefore, further studies need to be done.

Complete improvement in a patient with multiple irreversible defects of the left ventricle on 99m technetium-sestamibi SPECT after percutaneous coronary intervention

99mTc-sestamibi has been investigated as a potential viability marker; initial studies have shown good concordance between 201Tl and 99mTc-sestamibi activities in both viable and nonviable myocardium. However, assessment of myocardial viability by 99mTc-sestamibi remains controversial for tissue recovery after revascularization. Here, we present a patient with several regions of severely diminished and irreversible (defect persisting in both early and delay images of each set scanning) defects on initial scan which were dissolved completely on the follow up scan after an intervention. In a 75 year-old Asian woman with acute myocardial infarction who received thrombolytic therapy and subjected to percutaneous coronary angiography (PCI) on day 28 after acute myocardial infarction(MI), resting 99mTc-sestamibi SPECT was applied on day 4 (initial scan) and 138 (follow up scan) after acute MI at 30 and 180 min after injection of tracer (740 MBq); Two-dimensional echocardiography was carried out at the same time. On the initial image set, there was irreversible defects in the apex, anteroapical, inferoapical, anteroseptal, septal and also anterior walls, while the follow up image was normal in all regions.The angiography intervention showed just significant stenosis on left anterior descending (LAD) vessel (95%). This may highlight the failure of 99mTc-sestamibi as a marker of myocardial viability and also mandate further validating of the procedure with follow up scan or other modalities for myocardial viability investigation.

The role of 99mTc-MIBI scintigraphy in the management of patients with pulmonary tuberculosis

BACKGROUND

This study aimed to determine whether 99mTc-methoxyisobutylisonitrile (MIBI) scanning could improve diagnostic accuracy of pulmonary tuberculosis (PTB) and help clinical decision making for an accurate management.

MATERIAL AND METHODS

99mTc-MIBI scintigraphy was performed in 62 cases of PTB 34 cases had active pulmonary tuberculosis (APTB) and were at the beginning of antituberculosis medication (group 1) as well as 28 cases had inactive pulmonary tuberculosis (IPTB) and were post antituberculosis medication (group 2). The qualitative and semiquantitative findings of both scanning methods were assessed. For semiquantitative evaluation, regions of interest (ROIs) were drawn over the lesion (L), non-lesion (NL) and neck soft tissue (NST). The mean count values of ROIs were obtained and L/NL and L/NST were calculated.

RESULTS

Thirty-four patients with APTB (15 males and 19 females; mean age of 47.85 +/- 1.91 yrs) and 28 cases with IPTB (9 male and 19 females; mean age of 53.96 +/- 2.33 yrs) were included in this study. The sensitivity, specificity, accuracy, positive and negative predictive (PPV and NPV) values of 99mTc-MIBI were 88.2%, 75%, 82.2%, 81.1% and 84% respectively. The mean value of L/NL in the APTB for 99mTc-MIBI was 1.45 +/- 0.18 and L/NST was 1.57 +/- 0.26 which was significant statistically (p < 0.00).

CONCLUSIONS

The study demonstrated that 99mTc-MIBI scanning can be complementary to other diagnostic techniques especially in patients with indeterminate APTB and those in whom recurrent disease is suspected. In addition, because of its availability, rather low costs, easy performance, and objective semiquantitative information supplied, 99mTc-MIBI scanning might be establish in routine imaging center to assess the pulmonary tuberculosis. However, further exploration is needed to validate its clinical role.

The association of rate pressure product (RPP) and myocardial perfusion imaging (MPI) findings: a preliminary study

Introduction: The product of heart rate and systolic blood pressure, termed as rate-pressure product (RPP), is a very reliable indicator of myocardial oxygen demand and is widely used clinically. There have been previous attempts to describe the relationship between RPP and the onset of pain in angina pectoris. The current study aimed to evaluate the association between RPP results and scan findings.

Materials and methods: In total, 497 patients with suspected coronary artery disease (CAD) underwent gated, single-photon emission computed tomography (SPECT) imaging with dipyridamole, exercise, or dobutamine stress, and were included in this study. Baseline and maximum heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and electrocardiogram (ECG) results were recorded. The rate-pressure product (RPP) was calculated as the product of heart rate and systolic arterial pressure for both baseline and maximum measures. The difference between the RPP max and the basal RPP is known as the RPP reserve. Researchers also obtained semi-quantitative analyses of myocardial perfusion imaging (MPI), using gated software, demographic information, risk factors of CAD, and pretest likelihoods of CAD using nomograms.

Result: Four hundred and ninety-seven cases, including 426 patients with dipyridamole stress, 59 with exercise stress, and 12 with dobutamine stress, underwent myocardial perfusion imaging. Scan results were positive in 194 (45.5%) and negative in 232 (54.5%) patients with dipyridamole stress. In patients with exercise stress, the scan was positive in 24 (40.7%) cases and negative in 35 (59.3%) cases. In dobutamine stressed patients, the scan was positive in 6 (50%) cases and negative in the 6 remaining cases. Dipyridamole stress resulted in a significant difference between HR at rest and at maximum (28.95 ± 24.53, p-value<0.0001), between systolic BP at rest and maximum (6.75 ± 12.50, p-value<0.0001) and between diastolic BP at rest and maximum (1.45 ± 5.80; p-value<0.0001). There was a significant correlation between sum stress scores (SSS) and reserved RPP (r= −0.12, p-value<0.001) which, in dipyridamole patients, was r=−0.18, p-value=0.0001). In addition, there was a significant association between reserved RPP and risk of CAD (p-value<0.001). In the patients with dipyridamole stress, the ejection fraction (EF) change (odds ratio =0.92; 95% CI: 0.86-0.98; p=0.01), reserve RPP (odds ratio =1.00; 95% CI: 1.00-1.00; p=0.04), risk of CAD (odds ratio =5.80; 95% CI: 3.21-10.50; p<0.0001) and age (odds ratio =0.94; 95% CI: 0.89-0.98; p=0.01) were associated significantly with MPI results, using multiple logistic regressions.

Conclusion. The study demonstrated that RPP is associated with MPI findings using gated SPECT imaging with dipyridamole stress. However, to confirm this preliminary result, further studies are mandatory.

Scintigraphic parameters with emphasis on perfusion appraisal in rest 99mTc-sestamibi SPECT in the recovery of myocardial function after thrombolytic therapy in patients with ST elevation myocardial infarction (STEMI)

Introduction: This study was performed to determine the clinical application of rest 99mTc-sestamibi in the assessment of viability and functional improvement of the left ventricle (LV) myocardium in the post-thrombolytic therapy of acute myocardial infarction (AMI). Material and methods: In 37 patients with AMI who received thrombolytic therapy, 2-dimensional (2D) echocardiography, as well as the resting redistribution of 99mTc-sestamibi, was investigated, both within 1 week and 3–5 months after AMI. The predictive capacity of the perfusion percentage for myocardial function recovery was evaluated. Also, the capacities of the possible variables in the prediction of recovery of myocardial function resulting from a change in LV ejection fraction (EF) were evaluated using stepwise multiple regression analysis. Results: Thirty-seven patients (30 men and 7 women; mean age: 58±14 years) with AMI were enrolled in the study. Redistribution was observed in 35 and 50 segments of the initial and follow-up scans, respectively. In addition, 146 segments with reverse redistribution (RR), both in the initial scan (118 segments) and the follow-up scan (86 segments), were also observed. An apparent difference in wall motion scores was seen between the initial and follow-up echocardiographs (p<0.001). Furthermore, using the optimal cut-off point of perfusion percentage in each image set, sensitivity as well as specificity and likelihood ratio (LR) for the improvement of regional wall motion after 3–5 months were defined. Conclusion: These data showed that redistribution and reverse redistribution of 99mTc-sestamibi post thrombolytic therapy can be used as a marker of viability to predict the recovery of segmental wall motion abnormality (stunning), as well as the improvement of segmental perfusion uptake. This study also demonstrates that the resting 99mTc-sestamibi SPECT can be used for an approximate assessment of LV function status and can predict the recovery of jeopardized myocardium function after thrombolytic therapy.