Long-term use of burosumab for the treatment of tumor-induced osteomalacia.

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused by tumoral overproduction of FGF-23. Due to local recurrence, we describe the long-term efficacy and safety profile of burosumab, an anti-FGF-23 monoclonal antibody, in a TIO patient after three unsuccessfully surgical attempts. INTRODUCTION: TIO is a rare paraneoplastic syndrome caused by tumoral overproduction of fibroblast growth factor 23 (FGF23), resulting in hyperphospaturia, hypophosphatemia, and osteomalacia. Surgery is the only definitive treatment, but tumor can locally recur, even after years from primary surgery. Furthermore, some tumors cannot be removed by surgery due to their location. METHODS: We describe the case of a 54-year-old woman affected by recurrent TIO who, after three unsuccessful surgical attempts of tumor removal, was treated with burosumab, an anti-FGF-23 monoclonal antibody. RESULTS: The patient was referred to our Bone Unit after experiencing several fractures in different sites, both traumatic and non-traumatic. At the time of first evaluation, at the age of 46, serum-phosphate (SP) was 1.2 mg/dL (reference range (RR) 2.5-4.5), 24-h urinary phosphate was 842 mg (RR 400-1000), and intact-FGF-23 was 117 pg/mL (RR 25-45). Imaging showed a metabolic pre-sacral lesion that firstly underwent to exploratory laparotomy. Then, patient underwent to surgical excision of tumor. After 18 months of well-being, tumor relapsed and even the subsequent surgery was not able to completely remove it. Since 2015, patient was maintained in phosphorus supplements and 1,25(OH)2vitamin D3, but SP levels never normalized. In September 2019, she was started on burosumab, initially at the dose of 0.3 mg/kg/month, progressively increased to the current 0.8 mg/kg/month, with great improvement of pain, physical performance, and normalization of SP levels. Burosumab was temporary and cautionary discontinued for COVID-19 pneumonia, with a worsening of SP. After restart of burosumab, biochemistry returned to normal. CONCLUSIONS: To our knowledge, this is the first European patient affected by TIO treated with burosumab for more than 2 years. Burosumab is a promising therapy in the medical treatment of TIO refractory or not eligible for definitive surgery, with good efficacy and safety profile.

A novel mutation in collagen gene COL1A2 associated with transient regional osteoporosis.

A young man was diagnosed with transient regional osteoporosis (TRO). The genetic analysis revealed a novel de novo likely pathogenic variant in COL1A2 gene. Our hypothesis is that TRO may be a possible clinical manifestation of osteogenesis imperfecta due to a reduced bone mass and an impaired trabecular mechanical competence. INTRODUCTION: Transient regional osteoporosis (TRO) is a disease characterized by episodes of pain in the lower limbs involving the hip, knee, ankle or foot. Here, we present a clinical case of a Caucasian 25-year-old man exhibiting TRO. Based on few mild clinical findings suggestive of osteogenesis imperfecta (OI), but without a history of fragility fractures, we performed a genetic assessment to investigate this hypothesis. METHODS: Medical history was obtained from the patient and family members, including biochemical, RMI and DXA assessments. Next-generation sequencing of COL1A1, COL1A2, COL2A1, CASR, CYP19A1, CUL7, CRTAP, KAL1, LEPRE1, LRP5, PPIB and SLC9A3R1, genes involved in juvenile osteoporosis, was performed. RESULTS: We identified a novel de novo heterozygous missense variant, c.488G > A, in exon 11 of the COL1A2 gene (NM_000089.3), resulting in the putative p.Gly163Asp substitution in the N-terminal part of the helical domain of type I collagen. The variant was predicted to be damaging by the in silico prediction tools and the mutation was therefore classified as likely pathogenic. This mutation can affect skeletal health impairing bone mass and trabecular mechanical competence, inducing a disease whose features strictly evoke a TRO. CONCLUSION: The present study describes a novel de novo heterozygous missense variant in COL1A2 gene, possibly inducing a propensity to trabecular microfractures. The recurrent symptomatic bone marrow oedema episodes could be the clinical picture consistent with the hypothesis of an inherited connective tissue disorder giving bone fragility.

Decreasing severity of Paget's disease of bone in northern Italy over the last two decades: results of a monocentric study on 391 patients.

Patients with Paget's disease of bone recruited over the last 20 years by a single centre were evaluated to find possible clinical changes. All markers of severity showed consistent downward trends. A reduced disease incidence could seemingly refer to lower sensitivity of the diagnostic tools owing to lower severity. INTRODUCTION: This study aimed to evaluate if the severity of Paget's disease of bone (PDB) is decreasing and whether a milder phenotype can have affected the results of studies on disease prevalence. METHODS: From August 2007 to August 2019, 167 patients with PDB were referred to our centre. Demographic and clinical characteristics were collected and compared with those of a sample of 224 patients enrolled in the same setting between January 2000 and July 2007. Multivariate analyses on 391 patients as a whole were performed assuming the year of presentation as explanatory variable. RESULTS: Patients of newer sample were diagnosed at a significantly older age (64.0 ± 11.3 vs 61.1 ± 11.6; p = 0.01). By comparing clinical features acknowledged as markers of disease severity, the mean number of involved bones, the proportion of skeletal involvement, and pre-treatment serum alkaline phosphatase (SAP) values all showed significant decreases (p < 0.001) in the more recent sample. Multivariate analyses confirmed these results for the latter two indices. Further markers of disease severity such as the prevalence of monostotic disease and normal SAP at diagnosis showed the same trend. The sensitivity of tools allowing incidental diagnosis in asymptomatic patients showed a reduced sensitivity: -11% for radiological assessments and -33% for SAP. CONCLUSIONS: Allowing for referral differences, our study provides information on reduced severity of PDB over the last two decades. A milder phenotype affects the age at onset and impairs the sensitivity of the diagnostic tools contributing to reduce the prevalence of PDB patients incidentally discovered.

The association between osteoporosis and hypertension: the role of a low dairy intake.

Hypertension and related cardiovascular diseases are reported to be associated with osteoporosis. A nutritional pathway related to dairy intake has been postulated for both diseases. The aim of this study was to assess calcium intake from dairy sources as a possible pathogenic link between osteoporosis and hypertension. This was a cross-sectional observational study performed on 3,301 postmenopausal women referred for a densitometry screening. Osteoporosis was diagnosed by lumbar dual-energy X-ray absorptiometry and hypertension was defined by blood pressure data and/or the use of antihypertensive medication. Dairy food consumption was evaluated using a weekly food-frequency questionnaire. The odds of being affected by osteoporosis, hypertension, or both diseases were calculated for quartiles of dairy intake by logistic regression analyses. Women with hypertension were affected more frequently by osteoporosis (33.2 vs. 23.3 %; p = 0.000), and there was a higher prevalence of hypertension among women with osteoporosis (32.2 vs. 22.5 %; p = 0.000). The proportion of women with hypertension, osteoporosis, and both diseases significantly increased across decreasing quartiles of dairy intake. A dairy intake in the lowest quartile was a significant predictor of osteoporosis [OR (95 % CI): 1.43 (1.12, 1.82)] and hypertension [OR (95 % CI): 1.46 (1.15, 1.85)] when compared to the highest quartile. Similarly, a low dairy intake was associated with increased odds to have both the diseases [OR (95 % CI): 1.60 (1.10, 2.34)]. From these results we conclude that osteoporosis and hypertension are associated in postmenopausal women, and a low dairy intake may increase the risk of both diseases, acting as a possible pathogenic link.

How the COVID-19 pandemic affected bone health: a retrospective, longitudinal study on denosumab persistence from the epicentre of European spreading.

In this study, we investigated how the COVID-19 pandemic involved osteoporosis care in patients treated with denosumab. Almost a third of patients missed the prescription renewal, mandatory to obtain the subsidized drug. Among patients who suspended denosumab, more than half reported fragility fractures. PURPOSE: This study aimed to evaluate persistence on denosumab (Dmab) treatment during the COVID-19 pandemic and the clinical effects of possible discontinuation. METHODS: We retrospectively assessed patients affected by osteoporosis and treated with Dmab, scheduled to have the yearly renewal of prescription between March 9, 2020, and May 9, 2021, 2 months after the second pandemic wave. In June 2022, a telephone survey started, by calling all patients who missed the yearly renewal of Dmab. Predictors of missed renewal and fragility fracture occurrence were assessed by logistic analyses. RESULTS: Patients scheduled to have a renewal of Dmab prescription during the observational period were 538 (age 75.5 ± 9.3 years, female 511). A total of 152 (28.2%) patients did not have the renewal. Patients not renewing Dmab prescription were significantly older (p = 0.01) and more frequently affected by pulmonary (p = 0.04) and cardiovascular comorbidity (p = 0.01). Telephone survey on non-persistent patients showed that 44 had died, 28 patients were missing, 23 shifted to bisphosphonate treatment, and 22 patients suspended Dmab. Following discontinuation, 12/22 patients (54.5%) reported fragility fractures; 5/22 had multiple fractures, for a total number of 18 fractures, mainly vertebral. Logistic analyses showed that the odds of Dmab withdrawal increased in older patients with pulmonary comorbidity and treated for a shorter time. Dmab discontinuation was the only variable that increased the risk of fracture. CONCLUSION: This study provided real-world data about an impaired persistence of Dmab treatment resulting in an increased number of fragility fractures in a geographic area heavily affected by the outbreak of COVID-19.

Tumor induced osteomalacia: A single center experience on 17 patients.

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome due to a phosphaturic tumor, which overproduces Fibroblast Growth Factor 23 (FGF-23), causing hyperphosphaturia, hypophosphatemia, low 1,25(OH)2D and osteomalacia. Tumor localization is critical, diagnostic delay ranges from 2.5 to 28 years and to date surgical removal is considered effective treatment. We retrospectively evaluated patients with definite diagnosis of TIO referred to a tertiary Rheumatology Center between September 2000 and May 2020, investigating clinical management and disease outcome. We included 17 patients: 10 (58.8%) were females, mean age at diagnosis was 55.3 ± 13.9 years (mean ± standard deviation), with a diagnostic delay from symptoms onset to tumor detection of 6.6 ± 6.25 years. Biochemical data were: serum phosphorus 1.3 ± 0.4 mg/dL (Reference Range: 2.5-4.6), serum 1,25(OH)2D 31.8 ± 22.9 ng/mL (RR: 25-86), intact FGF-23, 358.9 ± 677 pg/mL (RR: 25-45); 24 h-Urine Phosphorus was increased in only 2 patients, while tubular reabsorption of phosphate (TRP) was decreased in all patients confirming a renal phosphate wasting. In 2013 68Ga- DOTA-based PET/CT was introduced in routinely practice and diagnostic delay was consistently reduced (from 8.6 ± 7.9 to 4.3 ± 2.4 years). Thirteen patients underwent surgery, one patient underwent radiofrequency ablation; 3 patients, not eligible for surgery, were treated only with supplements of phosphorus and calcitriol. One was started on Burosumab after several unsuccessful surgical attempts. After surgery or ablation, 8 patients had complete remission, 3 TIO persistence, and 3 had overtime relapse. Relapses were observed only in patients who previously underwent closed biopsy. To our knowledge, this is the widest European cohort of TIO patients in the last two decades. We confirm a usual diagnostic delay and recommend a stepwise diagnostic approach. Tumor biopsy is not recommended due to the potential cell spilling. Surgery is generally considered a definitive treatment, even though other approaches have been successful in curing TIO. Active surveillance on possible recurrence is always needed. Burosumab appears a promising therapy.

Mitotic crossing-over induced by two commercial herbicides in diploid strains of the fungus Aspergillus nidulans.

Some herbicides are suspected of promoting teratogenic, carcinogenic and mutagenic events. Detection of induced mitotic crossing-over has proven to be an indirect way of testing the carcinogenic properties of suspicious substances, because mitotic crossing-over is involved in the multistep process of carcinogenesis. We examined mitotic crossing-over induced by two commercial herbicides (diuron and trifluralin) in diploid strains of Aspergillus nidulans based on the homozygotization index. Low doses (2.5 microg/mL) of diuron were sufficient to increase the mean homozygotization index in 2.1 and 11.3 times for UT448//UT196 and Dp II-I//UT196, respectively, whereas the same dose of trifluralin increased this mean only 1.2 (UT448//UT196) and 3.5 (Dp II-I//UT196) times, respectively. The lower homozygotization index value found for trifluralin could be due to its interference with mitotic crossing-over in eukaryotic cells. We concluded that the diploid Dp II-I//UT196 of A. nidulans is more sensitive to organic compounds than UT448//UT196; these compounds cause recombinational events at a greater frequency in the latter diploid. This system holds promise as an initial test for carcinogenicity of organic compounds, including herbicides.

Aspergillus nidulans as a biological system to detect the genotoxic effects of mercury fumes on eukaryotes.

Mercury (Hg) pollution is one of the most serious environmental problems. Due to public concern prompted by the symptoms displayed by people who consumed contaminated fish in Minamata, Japan in 1956, Hg pollution has since been kept under constant surveillance. However, despite considerable accumulation of knowledge on the noxious effects of ingested or inhaled Hg, especially for humans, there is virtually nothing known about the genotoxic effects of Hg. Because increased mitotic crossing over is assumed to be the first step leading to carcinogenesis, we used a sensitive short-term test (homozygotization index) to look for DNA alterations induced by Hg fumes. In one Aspergillus nidulans diploid strain (UT448//UT184), the effects of the Hg fumes appeared scattered all over the DNA, causing 3.05 times more recombination frequencies than the mean for other strains. Another diploid (Dp II-I//UT184) was little affected by Hg. This led us to hypothesize that a genetic factor present in the UT184 master strain genome, close to the nicB8 genetic marker, is responsible for this behavior. These findings corroborate our previous findings that the homozygotization index can be used as a bioassay for rapid and efficient assessment of ecotoxicological hazards.

Fas/CD95 promoter polymorphism gene and its relationship with cervical carcinoma.

OBJECTIVE: Apoptosis is an important fail-safe control in human papillomavirus (HPV)-associated carcinogenesis. We tested the hypothesis that the A/G polymorphism at -670 of Fas promoter is associated with an increased risk for cervical cancer, using a matched case-control setting. METHODS: The material in this case-control study consisted of 91 patients with cervical carcinoma and 176 population-based control subjects, recruited between 2002 and 2004; all the ethnic Brazilian women had histologically confirmed cervical carcinoma. Control subjects were age-matched; healthy women who were selected following a negative cervical cytology and normal colposcopy. Fas genotyping was performed using a PCR-RFLP technique. RESULTS: No significant difference existed in the distribution of the Fas polymorphisms (wild, heterozygous, mutant) between the cases and controls. The heterozygous (OR: 4.85, 95% CI: 1.1-22.6) genotypes among the younger (< 48 yrs) cancer patients were almost 5-fold increased, as compared with the wild type. No such increase was observed among the patients older than 48 years. CONCLUSIONS: Our data suggest that 670A/G polymorphism in the promoter region of the death receptor Fas is associated with an increased risk of cervical cancer among Brazilian women under 48 years. The mechanisms would be the inhibition of apoptosis by Fas -670G allele-mediated down-regulation of Fas transcription.

Variant estrogen receptor messenger RNA species detected in human primary hepatocellular carcinoma.

The development of hepatocellular carcinoma (HCC) in addition to cirrhosis affects males in a significantly higher proportion than females. Liver estrogen receptors increase when HCC develops in males; however, these tumors usually respond poorly to antiestrogens. We have, therefore, hypothesized that, similar to breast cancer, estrogen receptors in males with HCC may be mutated. Variant estrogen receptor transcripts (lacking exon 5 of the hormone binding domain) were investigated by reverse transcription-PCR in 14 patients (7 males and 7 females) with HCC. While females mostly displayed the wild-type transcript (both in peritumoral and in tumor liver tissue), males showed both transcripts in the cirrhotic tissue and almost only the variant in the tumor. As the variant ER transcripts when translated could give rise to truncated receptors still able to constitutively activate transcription, they may be key factors in favoring deregulated proliferation in the male liver.

Intravenous pamidronate in the treatment of transient osteoporosis of the hip.

The aim of this study was to evaluate the efficacy of intravenous pamidronate in patients with transient osteoporosis of the hip (TOH). Thirteen men and three women (mean age 38.3 years, range 30-49) were recruited. The diagnosis was made by means of radiographs, bone scintigraphy, and magnetic resonance imaging (MRI). Pamidronate (45 mg) was intravenously administered three times, once every third day. The outcome measures included a clinical assessment using a pain visual analog scale (VAS; range 0-100), and the WOMAC functional impairment score (FUI; range 0-100). The bone mineral density (BMD) of the total hip and femoral neck was measured using dual-energy X-ray absorptiometry (DXA). Clinical assessments were made before treatment (T(0)) and 1 month later (T(1)), and the densitometric measurements at T(0), and then after 2 (T(2)) and 4 months (T(4)). A further MRI scan was made 3 months after treatment. In comparison to the unaffected side, there was a significant decrease at T(0) in the BMD of both the total hip (median 16.6%, range 8.5%-29.1%, p < 0.00001) and femoral neck (median 22.5%, range 12.0%-34.2%, p < 0.00001). By T(1), both VAS and FUI had decreased significantly (p < 0.00001). By T(2), the total hip and femoral neck BMD had increased by 10.9% (range 2.7%-23.6%, p < 0.00001) and 12.3% (range 7.8%-26.9%, p < 0.00001), respectively, and all patients were asymptomatic. By T(3), the MRI findings had normalized in all patients and, at T(4), there was a further increase in BMD. None of the patients experienced symptom relapse during the follow-up of 39.5 +/- 17.7 months. These results suggest that a short course of pamidronate is effective in treating TOH, and leads to a prompt and long-lasting recovery.

Reflex sympathetic dystrophy syndrome following acute gouty arthritis.

The unusual case of reflex sympathetic dystrophy syndrome caused by an acute attack of gout is reported. The syndrome, involving the left ankle and hindfoot, developed twelve days after a classical gouty attack involving the first metatarso-phalangeal joint of the same foot. Diagnosis was based on X-ray and scintigraphic and MRI changes A prompt clinical remission was achieved with a short course of i.v. clodronate.

Tensile strength of Cr-Co dental alloys solder joints.

Modifications and repairs of removable partial dentures usually involve solder joints. It is important to know the combination of solder and alloy that will provide the strongest junction. The purpose of this work was to investigate the mechanical strengths of different solders commonly used in dental practice. Specimens of three removable partial denture alloys (Dentitan, Crutanium, Wisil) were soldered with various solders having different melting temperatures. The soldered specimens were subjected to tensile testing, and the fracture surfaces were examined by means of scanning electron microscopy. Most of the failures occurred within the soldered joint, which is the weakest portion of a removable partial denture. Excessive use of flux to achieve an adequate flow of solder produced defects in the solder joint. A relationship was found between joint strength and solder fusion temperature for Crutanium and Wisil--the higher the fusion temperature, the higher the joint strength.

Influence of corrosion on brazed joints' strength.

The influence of corrosion on the bond strength of different brazed joints commonly used in dentistry has been investigated by means of accelerated immersion tests in artificial saliva buffered at pH 2, and in Ringer's solution, both kept at 37 degrees C. Two Co-Cr base metal alloys were brazed with a gold and a non-precious alloy. After 60 days' immersion the tensile strength of the samples brazed with the gold alloy was dramatically reduced because of galvanic corrosion phenomena. The bond strength of the specimens brazed with the non-precious alloy was largely unaffected. Corrosion products rich in nickel were detected. The electrochemical characterization of the base metal alloys and brazing materials was performed by means of polarization curves in the two media investigated. High short circuit currents were only produced with the gold brazing materials.

P27 expression in normal epithelium and condylomas of the vulva in HIV positive and negative women.

PURPOSE: The objective of the present study was to evaluate the expression of the p27 protein in the normal epithelium and vulvar condylomas in human immunodeficiency (HIV) positive and negative patients. METHODS: Eight samples of normal vulvar epithelium were evaluated (Group A), ten of the HIV negative vulvar condyloma patients (Group B) and another eight of the vulvar condyloma HIV positive patients (Group C). The DNA of human papillomavirus (HPV) was identified by means of polymerase chain reaction (PCR). Immunohistochemistry was the method used to evaluate the expression of p27 using monoclonal mouse antibody (Monoclonal Mouse, anti-human p27, Clone Sx 53 G8). The immunoexpression was evaluated at a magnification of 400x, counting a minimum of 1,000 cells per slide. RESULTS: The results obtained were the following: a) comparing groups A and B and groups A and C there was a significant difference in relation to the expression of the p27 protein which was 63.32% in group A and only 13.35% and 18.89% in groups B and C, respectively; b) comparing groups B and C among them, there was no significant difference. CONCLUSION: We concluded that in normal vulvar tissue the p27 protein is present in a large number of cells and that in vulval condylomas its expression is very much lowered both in HIV positive and negative cases.

[Electrochemical behavior of 3 magnetic alloys used for prosthetic retention]. / Comportamento elettrochimico di tre accoppiamenti magnetici impiegati per la ritenzione protesica.

By means of potentiodynamic techniques the electrochemical behaviour of a ferromagnetic alloy Pd-Co and three types of caps (AISI 316 stainless steel, Pd, Ti) for permanent Sm-Co magnets has been investigated in artificial saliva and in Ringer's solution. In addition short-circuit measurements were performed on several couples Pd-Co/AISI 316, Ti, Pd caps. From our findings a good corrosion resistance of all the materials is evidenced in artificial saliva. In Ringer's solution, which is more aggressive, Pd-Co shows no tendency to passivity.

Corrosion under static and dynamic conditions of alloys used for magnetic retention in dentistry.

In recent years magnetic retention has gained increasing popularity in dental practice. This investigation compared the corrosion resistance of the palladium-cobalt ferromagnetic alloy (constituent of the keeper cemented on the abutment teeth) coupled with the samarium-cobalt magnets embedded in the removable part of the denture. The behavior of three couples (cobalt-palladium, cobalt-palladium/titanium, and cobalt-palladium/palladium) has been studied. The magnets, because of their poor corrosion resistance, are encapsulated in various materials. To simulate clinical conditions, characterized by the continuous movement of the keeper with respect to the magnet, the experiments were conducted in artificial saliva under intermittent and continuous wear.