In Vitro Comparison to Evaluate Metal Ion Release: Nickel-Titanium vs. Titanium-Molybdenum Orthodontic Archwires

Background When metals used in orthodontic materials are exposed to the oral environment, teeth, and gingivae over an extended period of time, they may gradually deteriorate. As a result, the patient is exposed to higher concentrations of metals and metal ions than what they would be exposed to through food and other sources. The goal of the current in vitro experiment was to evaluate and contrast the metal ion release from orthodontic archwires made of titanium-molybdenum alloy (TMA) and nickel-titanium (NiTi). Methods For 90 days, 20 orthodontic archwires in each group were immersed in 50 milliliters of simulated saliva using different containers. Atomic Absorption Spectrometry (AAS) (Shimadzu Corporation, Kyoto, Japan) was used to assess and compare metal ion emission. The unit of measurement is parts per million (PPM). Results The findings indicated that the discharge of nickel metal from the NiTi archwire (Group A) was much higher than that from the TMA archwire (Group B), with a statistical significance level of p < 0.001. It was discovered that Group B's release of titanium was statistically significantly (p < 0.05) higher than Group A's titanium release, which did not include the release of any other metals. Conclusion The study findings indicated that the amounts of metal ions released from the orthodontic archwires made of titanium molybdenum and nickel-titanium alloy were within safety limits.

Frequency and characteristics of chemotherapy-associated thrombotic microangiopathy: Analysis from a large pharmacovigilance database

We used the information component (IC), a disproportionate Bayesian analysis comparing the number of observed versus expected adverse drug reactions, to determine the potential association between anti-neoplastic agents and thrombotic microangiopathy (TMA). The IC025 indicates the lower end of 95% of IC, in which a value >0 suggests a disproportionality signal between the drug of interest and the adverse drug reaction. Carfilzomib had the highest IC025 for TMA among all studied chemotherapies followed by gemcitabine, mitomycin, bevacizumab, and bortezomib.

A Rare Case of Thrombotic Thrombocytopenic Purpura (TTP) With Concurrent Renal Cell Carcinoma: Diagnostic and Therapeutic Challenges

Thrombotic thrombocytopenic purpura (TTP) is a potentially life-threatening thrombotic microangiopathy (TMA) that needs prompt identification and treatment. Disseminated malignancy-related TMA can potentially be misdiagnosed as TTP, and patients may be inappropriately subjected to therapeutic plasma exchange (TPE) with serious implications. Likewise, the presence of a concurrent cancer diagnosis in a patient with microangiopathic hemolytic anemia and thrombocytopenia may lead to suspicion of disseminated malignancy as the cause, delaying the TPE with serious outcomes. Testing for ADAMTS13 activity is diagnostic of TTP, but the results may take time. This poses a diagnostic and therapeutic dilemma that includes weighing the benefits of TPE for treating TTP and cancer treatment. We describe a rare case of immune-mediated TTP in a patient concurrently diagnosed with metastatic renal cell cancer. To our knowledge, this is the first case of TTP reported in patients with metastatic renal cell carcinoma (RCC) in a non-treatment-naive patient.

Malignancy diseases and kidneys: A nephrologist prospect and updated review

Acute kidney injury (AKI), chronic renal failure, and tubular abnormalities represent the kidney disease spectrum of malignancy. Prompt diagnosis and treatment may prevent or reverse these complications. The pathogenesis of AKI in cancer is multifactorial. AKI affects outcomes in cancer, oncological therapy withdrawal, increased hospitalization rate, and hospital stay. Renal function derangement can be recovered with early detection and targeted therapy of cancers. Identifying patients at higher risk of renal damage and implementing preventive measures without sacrificing the benefits of oncological therapy improve survival. Multidisciplinary approaches, such as relieving obstruction, hydration, etc., are required to minimize the kidney injury rate. Different keywords, texts, and phrases were used to search Google, EMBASE, PubMed, Scopus, and Google Scholar for related original and review articles that serve the article's aim well. In this nonsystematic article, we aimed to review the published data on cancer-associated kidney complications, their pathogenesis, management, prevention, and the latest updates. Kidney involvement in cancer occurs due to tumor therapy, direct kidney invasion by tumor, or tumor complications. Early diagnosis and therapy improve the survival rate. Pathogenesis of cancer-related kidney involvement is different and complicated. Clinicians' awareness of all the potential causes of cancer-related complications is essential, and a kidney biopsy should be conducted to confirm the kidney pathologies. Chronic kidney disease is a known complication in malignancy and therapies. Hence, avoiding nephrotoxic drugs, dose standardization, and early cancer detection are mandatory measures to prevent renal involvement.

Chemotherapy-Associated Thrombotic Microangiopathy

Thrombotic microangiopathy (TMA) is a syndrome of microangiopathic hemolytic anemia and thrombocytopenia with end-organ dysfunction. Although the advent of plasma exchange, immunosuppression, and complement inhibition has improved morbidity and mortality for primary TMAs, the management of secondary TMAs, particularly drug-induced TMA, remains less clear. TMA related to cancer drugs disrupts the antineoplastic treatment course, increasing the risk of cancer progression. Chemotherapeutic agents such as mitomycin-C, gemcitabine, and platinum-based drugs as well as targeted therapies such as antiangiogenesis agents and proteasome inhibitors have been implicated in oncotherapy-associated TMA. Among TMA subtypes, drug-induced TMA is less well-understood. Treatment generally involves withdrawal of the offending agent and supportive care targeting blood pressure and proteinuria reduction. Immunosuppression and therapeutic plasma exchange have not shown clear benefit. The terminal complement inhibitor, eculizumab, has shown promising results in some cases of chemotherapy-associated TMA including in re-exposure. However, the data are limited, and unlike in primary atypical hemolytic uremic syndrome, the role of complement in the pathogenesis of drug-induced TMA is unclear. Larger multicenter studies and unified definitions are needed to elucidate the extent of the problem and potential treatment strategies.

Hypertension-Induced Thrombotic Microangiopathy Leading to End-Stage Renal Disease

Thrombotic microangiopathy (TMA) is a term used for a group of rare and life-threatening hematological conditions. Usually, these disease processes are characterized by microangiopathic hemolytic anemia (MAHA), thrombocytopenia, and microthrombi leading to tissue or organ injury. We present a case of a 41-year-old male with TMA induced by uncontrolled hypertension leading to end-stage renal disease requiring hemodialysis. Our goal is to highlight the importance of distinguishing hypertension-induced thrombotic microangiopathy from other etiologies of TMA, particularly thrombotic thrombocytopenic purpura (TTP), and its effect on renal function despite treatment focused on blood pressure control. Thus, it is a challenging diagnosis for clinicians to determine whether to initiate plasmapheresis for prompt treatment of suspected TTP in the setting of severe hypertension with thrombocytopenia.

Sequential Infiltration Synthesis of Al2O3 in Biodegradable Polybutylene Succinate: Characterization of the Infiltration Mechanism

The introduction of inorganic materials into biopolymers has been envisioned as a viable option to modify the optical and structural properties of these polymers and promote their exploitation in different application fields. In this work, the growth of Al2O3 in freestanding ∼30-μm-thick poly(butylene succinate) (PBS) films by sequential infiltration (SIS) at 70 °C via trimethylaluminum (TMA) and H2O precursors was investigated for the first time. The incorporation of Al2O3 into the PBS matrix was clearly demonstrated by XPS analysis and SEM-EDX cross-sectional images showing a homogeneous Al2O3 distribution inside the PBS films. Raman measurements on infiltrated freestanding PBS show a reduction of the signal related to the ester carbonyl group as compared to pristine freestanding PBS films. Accordingly, FTIR and NMR characterization highlighted that the ester group is involved in polymer-precursor interaction, leading to the formation of an aliphatic group and the concomitant rupture of the main polymeric chain. Al2O3 mass uptake as a function of the number of SIS cycles was studied by infiltration in thin PBS films spin-coated on Si substrates ranging from 30 to 70 nm. Mass uptake in the PBS films was found to be much higher than in standard poly(methyl methacrylate) (PMMA) films, under the same process conditions. Considering that the density of reactive sites in the two polymers is roughly the same, the observed difference in Al2O3 mass uptake is explained based on the different free volume of these polymers and the specific reaction mechanism proposed for PBS. These results assessed the possibility to use SIS as a tool for the growth of metal oxides into biopolymers, paving the way to the synthesis of organic-inorganic hybrid materials with tailored characteristics.

Al2O3 Dot and Antidot Array Synthesis in Hexagonally Packed Poly(styrene-block-methyl methacrylate) Nanometer-Thick Films for Nanostructure Fabrication

Nanostructured organic templates originating from self-assembled block copolymers (BCPs) can be converted into inorganic nanostructures by sequential infiltration synthesis (SIS). This capability is particularly relevant within the framework of advanced lithographic applications because of the exploitation of the BCP-based nanostructures as hard masks. In this work, Al₂O₃ dot and antidot arrays were synthesized by sequential infiltration of trimethylaluminum and water precursors into perpendicularly oriented cylinder-forming poly(styrene-block-methyl methacrylate) (PS-b-PMMA) BCP thin films. The mechanism governing the effective incorporation of Al₂O₃ into the PMMA component of the BCP thin films was investigated evaluating the evolution of the lateral and vertical dimensions of Al₂O₃ dot and antidot arrays as a function of the SIS cycle number. The not-reactive PS component and the PS/PMMA interface in self-assembled PS-b-PMMA thin films result in additional paths for diffusion and supplementary surfaces for sorption of precursor molecules, respectively. Thus, the mass uptake of Al₂O₃ into the PMMA block of self-assembled PS-b-PMMA thin films is higher than that in pure PMMA thin films.

Manual Construction of a Tissue Microarray using the Tape Method and a Handheld Microarrayer

The tissue microarray (TMA) is an important research tool in which many formalin fixed paraffin embedded (FFPE) samples can be represented in a single paraffin block. This is achieved by using tissue cores extracted from the region of interest of different donor FFPE blocks and arranging them into a single TMA paraffin block. Once constructed, sections from the completed TMA can be used to perform immunohistochemistry, chromogenic, fluorescence in situ hybridization (FISH) and RNA ISH studies to assess protein expression as well as genomic and transcriptional alterations in many samples simultaneously, thus minimizing tissue usage and reducing reagent costs. There are several different TMA construction techniques. One of the most common construction methods is the recipient method, which works best with cores of the same length for which a minimum length of 4 mm is recommended. Unfortunately, tissue blocks can be heavily resected during the diagnostic process, frequently resulting in "non-ideal" donor block thicknesses of less than 4 mm. The current article and video focus on the double-sided adhesive tape method; an alternative manual, low cost, easy to use, and rapid method to construct low density (<50 cores) TMAs that is highly compatible with these non-ideal donor blocks. This protocol provides a step-by-step guide on how to construct a TMA using this method, with a focus on the critical importance of pathological review and post construction validation.

Rare Presentation of Atypical Hemolytic Uremic Syndrome in an Adult

Thrombotic microangiopathies (TMA) are disorders characterized by microangiopathic hemolytic anemia, thrombocytopenia, and microthrombi leading to organ dysfunction. Atypical hemolytic uremic syndrome (aHUS) is a rare subtype of TMA mediated by complement dysregulation. We present a case of a 59-year-old female who presented with acute kidney injury and mild thrombocytopenia but with normal hemoglobin. We highlight the importance of prompt diagnosis of aHUS and initiating appropriate treatment with eculizumab.

A Case of Repeated TAFRO Syndrome-Like Symptoms and Retroperitoneal Hemorrhage in a Patient With Sjögren Syndrome

A 50-year-old Japanese man complaining of dry mouth and eyes, pale skin with cold irritation, and worsening epigastric pain was admitted to the hospital, whereupon he developed fever and anasarca. A computed tomography (CT) scan showed ascites, hepatosplenomegaly, and mildly enlarged multiple lymph nodes, and blood examination revealed renal impairment, thrombocytopenia, and high levels of C-reactive protein (CRP). He was diagnosed with Sjögren syndrome and concurrently manifested symptoms resembling TAFRO syndrome (i.e., thrombocytopenia (T), anasarca (A), fever (F), reticulin fibrosis (R), and organomegaly (O)). Although the TAFRO syndrome-like symptoms progressed, he gradually recovered with immunosuppressive agents. Seven years and five months after the admission, the TAFRO syndrome-like symptoms recurred. Bone marrow biopsy specimens revealed reticulin fibrosis. Inguinal and mediastinal lymph nodes biopsy specimens revealed Castleman disease-like features. Although the symptoms indicated TAFRO syndrome, a diagnosis was not possible owing to the presence of hypergammaglobulinemia and Sjögren syndrome, which required exclusion. Corticosteroid treatment was initiated; however, it was complicated by retroperitoneal hemorrhage, probably due to microangiopathy. After additional treatment with tocilizumab and rituximab, the TAFRO syndrome-like symptoms improved and the hemorrhage progression stopped. In conclusion, TAFRO syndrome-like symptoms may recur with vascular complications and can be successfully treated with tocilizumab and rituximab during Sjögren syndrome. The etiology of TAFRO syndrome could potentially involve Sjögren syndrome, and these syndromes may co-exist.

SOX2 Is a Potential Novel Marker of Undifferentiated Thyroid Carcinomas

Background Thyroid cancer is a very common endocrine malignancy. Cancer stem cells are attributable to initiation, progression, and treatment failure in thyroid carcinoma. In the current study, immunostaining of SRY-box 2 (SOX2) in thyroid carcinoma is investigated. Material and methods Tissue microarrays were generated from 219 thyroid carcinomas distributed as follows: papillary thyroid carcinoma (175), follicular thyroid carcinoma (11), medullary thyroid carcinoma (11), Hurthle cell carcinoma (three), poorly differentiated thyroid carcinoma (PTDC; nine), and anaplastic thyroid carcinoma (ATC; 10). Immunohistochemistry for SOX2 was done and examined for nuclear staining. The results were analysed.  Results SOX2 immunostaining was positive in one PDTC (out of nine; 11.1%) and in three ATC (out of 10; 30%). The rest of the thyroid cancers showed no immunostaining for SOX2. Conclusion The study represents for the first time SOX2 immunostaining on a large number of thyroid carcinomas. We discovered that SOX2 immunostaining is found in PDTC and ATC while SOX2 immunostaining is lacking in other thyroid cancer. SOX2 may be a marker of loss of differentiation in thyroid carcinoma. In vitro as well as in vivo molecular studies are required to explore the possible role of SOX2 in thyroid carcinoma.

Torque efficiency of different archwires in 0.018- and 0.022-inch conventional brackets

OBJECTIVE

To compare the archwires inserted during the final stages of the orthodontic treatment with the generated moments at 0.018- and 0.022-inch brackets.

MATERIALS AND METHODS

The same bracket type, in terms of prescription, was evaluated in both slot dimensions. The brackets were bonded on two identical maxillary acrylic resin models, and each model was mounted on the orthodontic measurement and simulation system. Ten 0.017 × 0.025-inch TMA and ten 0.017 × 0.025-inch stainless steel archwires were evaluated in the 0.018-inch brackets. In the 0.022-inch brackets, ten 0.019 × 0.025-inch TMA and ten 0.019 × 0.025-inch stainless steel archwires were measured. A 15° buccal root torque (+15°) and then a 15° palatal root torque (-15°) were gradually applied to the right central incisor bracket, and the moments were recorded at these positions. A t-test was conducted to compare the generated moments between wires within the 0.018- and 0.022-inch bracket groups separately.

RESULTS

The 0.017 × 0.025-inch archwire in the 0.018-inch brackets generated mean moments of 9.25 Nmm and 14.2 Nmm for the TMA and stainless steel archwires, respectively. The measured moments in the 0.022-inch brackets with the 0.019 × 0.025-inch TMA and stainless steel archwires were 6.6 Nmm and 9.3 Nmm, respectively.

CONCLUSION

The 0.017 × 0.025-inch stainless steel and β-Ti archwires in the 0.018-inch slot generated higher moments than the 0.019 × 0.025-inch archwires because of lower torque play. This difference is exaggerated in steel archwires, in comparison with the β-Ti, because of differences in stiffness. The differences of maximum moments between the archwires of the same cross-section but different alloys were statistically significant at both slot dimensions.

Expression of the RNase III enzyme DROSHA is reduced during progression of human cutaneous melanoma

Aberrant expression of microRNAs (miRNAs) and their biogenesis factors has been frequently observed in different types of cancer. We recently reported that expression of DICER1 is reduced in metastatic melanoma. Nevertheless, so far very little is known about the expression pattern of other miRNA biogenesis factors in this type of malignancy. Here, we investigated the expression pattern of DROSHA in a large set of melanocytic lesions (n=409) by tissue microarray and immunohistochemistry. We found that nuclear expression of DROSHA is markedly reduced in the early stages of melanoma progression (P=0.0001) and is inversely correlated with melanoma thickness (P=0.0001), AJCC stages (P=0.0001), and ulceration status (P=0.002). We also confirmed the reduced expression of nuclear DROSHA by a second specific antibody raised against a different region of the DROSHA protein. In addition, we observed that the reduced nuclear expression of DROSHA during melanoma progression is accompanied by an increased cytoplasmic expression of this protein (P=0.0001). Finally, we found that expression pattern of DROSHA varies from that of DICER1 and concomitant loss of expression of both DICER1 and DROSHA confers the worse outcome for melanoma patients. Our results demonstrate a reduced nuclear expression of DROSHA, which further highlights a perturbed miRNA biogenesis pathway in melanoma. In addition, the aberrant subcellular localization of DROSHA indicates possible deregulation in the mechanisms responsible for its proper localization in the nucleus.

A metadata-aware application for remote scoring and exchange of tissue microarray images

BACKGROUND

The use of tissue microarrays (TMA) and advances in digital scanning microscopy has enabled the collection of thousands of tissue images. There is a need for software tools to annotate, query and share this data amongst researchers in different physical locations.

RESULTS

We have developed an open source web-based application for remote scoring of TMA images, which exploits the value of Microsoft Silverlight Deep Zoom to provide a intuitive interface for zooming and panning around digital images. We use and extend existing XML-based standards to ensure that the data collected can be archived and that our system is interoperable with other standards-compliant systems.

CONCLUSION

The application has been used for multi-centre scoring of TMA slides composed of tissues from several Phase III breast cancer trials and ten different studies participating in the International Breast Cancer Association Consortium (BCAC). The system has enabled researchers to simultaneously score large collections of TMA and export the standardised data to integrate with pathological and clinical outcome data, thereby facilitating biomarker discovery.

Transplant-associated thrombotic microangiopathy in pediatric patients treated with sirolimus and tacrolimus

BACKGROUND

Transplant-associated thrombotic microangiopathy (TMA) syndromes are reported to occur with increased frequency in transplant patients treated with siroliumus combined with a calcineurin inhibitor. We performed a retrospective study of all pediatric transplant patients at City of Hope who were administered combined tacrolimus/sirolimus (TAC/SIR) to determine the occurrence of TMA.

PROCEDURE

This analysis includes 41 consecutive patients between the ages of 2 and 20 (median age 9.1) who received an allogeneic hematopoietic stem cell transplant from any source and also received TAC/SIR for prevention or treatment of GVHD. Of those 41 patients, 20 received TAC/SIR as GVHD prohpylaxis and were designated the preventative group (PG), while 21 received TAC/SIR as treatment for GVHD and were designated the therapy group (TG). TMA occurrence in both groups was documented from day -1 of transplant to day 60 for the PG, and until 30 days after last dose for the TG. TMA was defined according to 2005 consensus criteria.

RESULTS

Five of twenty patients in the PG, and five of twenty one in the TG, experienced TMA, with an overall rate of 23.8% for the population. All ten patients with TMA showed elevated levels of TAC, SIR or both and nine of ten suffered from organ injury due to regimen-related toxicity or GVHD.

CONCLUSION

Physicians should exercise caution in the use of TAC/SIR in pediatric patients due to a high rate of TMA. It is not recommended for heavily pre-treated patients and peak levels of TAC/SIR must be very carefully controlled.

Prognostic value of Dicer expression in human breast cancers and association with the mesenchymal phenotype

BACKGROUND

Dicer, a ribonuclease, is the key enzyme required for the biogenesis of microRNAs and small interfering RNAs and is essential for both mammalian development and cell differentiation. Recent evidence indicates that Dicer may also be involved in tumourigenesis. However, no studies have examined the clinical significance of Dicer at both the RNA and the protein levels in breast cancer.

METHODS

In this study, the biological and prognostic value of Dicer expression was assessed in breast cancer cell lines, breast cancer progression cellular models, and in two well-characterised sets of breast carcinoma samples obtained from patients with long-term follow-up using tissue microarrays and quantitative reverse transcription-PCR.

RESULTS

We have found that Dicer protein expression is significantly associated with hormone receptor status and cancer subtype in breast tumours (ER P=0.008; PR P=0.019; cancer subtype P=0.023, luminal A P=0.0174). Dicer mRNA expression appeared to have an independent prognostic impact in metastatic disease (hazard ratio=3.36, P=0.0032). In the breast cancer cell lines, lower Dicer expression was found in cells harbouring a mesenchymal phenotype and in metastatic bone derivatives of a breast cancer cell line. These findings suggest that the downregulation of Dicer expression may be related to the metastatic spread of tumours.

CONCLUSION

Assessment of Dicer expression may facilitate prediction of distant metastases for patients suffering from breast cancer.

Trimellitic anhydride (TMA) dust induces airway obstruction and eosinophilia in non-sensitized guinea pigs

Trimellitic anhydride (TMA) causes asthma after a latency period of sensitization. In non-sensitized humans and animals, limited studies indicate that TMA exposure may also cause symptoms of asthma without a latency period. Our previous studies (J. Pharmacol. Exp. Ther. 296 (2001) 284) in a guinea pig model of TMA-induced asthma demonstrated that sensitization and the complement system were required for eosinophilia. TMA conjugated to guinea pig serum albumin (TMA-GPSA) was used to elicit the response. Since occupational exposure to TMA occurs by inhalation of dust, the present studies determined if exposure to TMA dust in a non-sensitized guinea pig elicited airway obstruction and inflammation, and whether a significantly greater response occurred after a latency period of sensitization. Guinea pigs were intradermally injected with either corn oil (non-sensitized animals) or 30% TMA (sensitized animals). Three weeks later they were challenged by intratracheal insufflation with 1 mg TMA dust or lactose dust (control) using a dry powder delivery device. Pulmonary resistance, dynamic lung compliance, mean arterial blood pressure and heart rate were monitored for 10 min. In non-sensitized guinea pigs, significant increases in pulmonary resistance and decreases in dynamic lung compliance and blood pressure occurred after TMA challenge. In sensitized animals, the same dose of TMA caused significantly greater effects compared to non-sensitized animals. In a separate experiment, cellular infiltration into the lung was determined 24 h after challenge with TMA dust or lactose dust. In both non-sensitized and sensitized animals, eosinophils in the lung tissue were increased after TMA dust challenge compared to controls. Thus, these studies suggest that the response in non-sensitized animals differs depending on whether TMA dust or TMA-GPSA is used to elicit the response. TMA dust elicits significant airway obstruction and eosinophilia in a non-sensitized animal, with even greater airway obstruction occurring in a sensitized animal.