Coupling defect of thyrotropin receptor and adenylate cyclase in a pseudohypoparathyroid patient

A patient with type I pseudohypoparathyroidism was found to have mild hypothyroidism. The patient had an elevated basal TSH level and an exaggerated TSH response to TRH. There was no goiter despite increased TSH levels, and the 131I thyroidal uptake was low before and after exogenous TSH administration. These studies suggested that the patient might have partial resistance to TSH. The binding of radioiodinated TSH to thyroid membranes obtained by biopsy was next studied. The displacement of iodinated TSH by unlabeled TSH was found to be identical to that in normal control membranes. The adenylate cyclase stimulation by a supramaximal dose of TSH, however, was blunted (120.1 +/- 11.5 vs. 387.2 +/- 40.3 pmol cAMP/min/mg protein), while basal and NaF-stimulated activities were quite similar to the activities in normal membranes. These findings suggested a lack of signal transmission between the TSH receptor and the catalytic unit. Incubation of control membranes with TSH and GTP resulted in a synergistic effect on the adenylate cyclase activity. This was not found with the patient's membranes and suggested that the coupling failure was due to a defective guanine nucleotide regulatory protein. We conclude that in this case of type I pseudohypoparathyroidism, the associated mild primary hypothyroidism was due to a partial TSH refractoriness caused by a coupling defect between the TSH receptor and adenylate cyclase. This observation suggests that a common pathogenetic mechanism might underly type I pseudohypoparathyroidism and its associated hypothyroidism.     

The Efficacy of Platelets Rich Plasma Injection in the Superior Joint Space of the Tempromandibular Joint Guided by Ultra Sound in Patients with Non-reducing Disk Displacement

Objective

The objective of this study was to determine average improvement during the rest and active mouth opening after ultrasound guided platelets rich plasma injection in the tempromandibular superior joint space for the patients complaining from non-reducing disk displacement.

Patients and Methods

Thirty-four patients with non-reducing disk displacement underwent guided ultrasound injection of platelet rich plasma to the upper joint space. The extent of maximal mouth opening, chewing efficiency, sound intensity of the TMJ, and tenderness of the TMJ and the masticatory muscles at rest, motion and mastication were thoroughly assessed at the beginning of the study and scheduled for next follow-up at 1st, 3rd, and 6th months.

Results

Injection with platelets rich plasma was significantly more effective in improvements of the extent of maximal mouth opening, statistics result demonstrated a significant reduction in the VAS values of pain at rest, motion and mastication compared to the baseline VAS values.

Conclusion

PRP injection to the upper temporomandibular joint space provided improvement in signs and symptoms of patient with non-reducing disk displacement of the temporomandibular joint.

     

Estimation of fluoride concentration in drinking water and common beverages in United Arab Emirates (UAE)

Objective

To assess fluoride concentration in drinking water which include tap water of 4 emirates - Abu Dhabi, Dubai, Sharjah and Ajman plus bottled water, commonly available soft drinks & juices in United Arab Emirates.

Clinical relevance of the utilization of vital Lugol’s iodine staining in detection and diagnosis of oral cancer and dysplasia

Clinical Oral Investigations - The aim of this study is to assess the clinical relevance of the utilization of vital Lugol’s iodine staining in detection of oral cancer and dysplastic lesions...     

Comparison of Fracture Risk Prediction among Individuals with Reduced and Normal Kidney Function

Background and objectives

The Fracture Risk Assessment Tool (FRAX) is widely used to predict the 10-year probability of fracture; however, the clinical utility of FRAX in CKD is unknown. This study assessed the predictive ability of FRAX in individuals with reduced kidney function compared with individuals with normal kidney function.

Design, setting, participants, & measurements

The discrimination and calibration (defined as the agreement between observed and predicted values) of FRAX were examined using data from the Canadian Multicentre Osteoporosis Study (CaMos). This study included individuals aged ≥40 years with an eGFR value at year 10 of CaMos (defined as baseline). The cohort was stratified by kidney function at baseline (eGFR<60 ml/min per 1.73 m² [72.2% stage 3a, 23.8% stage 3b, and 4.0% stage 4/5] versus ≥60 ml/min per 1.73 m²) and followed individuals for a mean of 4.8 years for an incident major osteoporotic fracture (clinical spine, hip, forearm/wrist, or humerus).

Results

There were 320 individuals with an eGFR<60 ml/min per 1.73 m² and 1787 with an eGFR≥60 ml/min per 1.73 m². The mean age was 67±10 years and 71% were women. The 5-year observed major osteoporotic fracture risk was 5.3% (95% confidence interval [95% CI], 3.3% to 8.6%) in individuals with an eGFR<60 ml/min per 1.73 m², which was comparable to the FRAX-predicted fracture risk (6.4% with bone mineral density; 8.2% without bone mineral density). A statistically significant difference was not observed in the area under the curve values for FRAX in individuals with an eGFR<60 ml/min per 1.73 m² versus ≥60 ml/min per 1.73 m² (0.69 [95% CI, 0.54 to 0.83] versus 0.76 [95% CI, 0.70 to 0.82]; P=0.38).

Conclusions

This study showed that FRAX was able to predict major osteoporotic fractures in individuals with reduced kidney function; further study is needed before FRAX should be routinely used in individuals with reduced kidney function.     

Primary breast angiosarcoma: a rare presentation of rare tumor – case report

Background

Primary breast angiosarcoma is defined as malignant proliferation showing endothelial differentiation. It is a very rare tumour (0.05% of primary mammary cancers), whose diagnosis can be difficult.

Case presentation

We report the observation of a patient with no previous history, aged 27 years. The clinical examination finds a right breast discreetly increased in volume. The trucut biopsy was in favour of a lactating tubular adenoma. However, an immunohistochemical complement was requested. An absence of pancytokeratin labelling contrasted with strong expression of CD31, CD34 (endothelial markers) are described. The proliferation index (Ki67) was estimated at 30%. This led to the conclusion that the phenotypic aspect is related to a vascular proliferation that evokes an angiosarcoma. After a multidisciplinary assessment, the patient benefited from an enlarged excision of the tumour. The histopathological examination of the surgical specimen found an infiltrating mesenchymal proliferation made of vessels of variable sizes anastomosed to vascular slits with lesional limits. The immunohistochemical examination on the surgical specimen showed to the same phenotypic profile on biopsy. The final diagnosis was a high-grade mammary angiosarcoma of incomplete excision. The patient refused any additional surgical management; external radiotherapy and close supervision were prescribed. After eight months of evolution, no local or remote recurrence was reported.

Conclusion

Primary breast angiosarcoma is a mesenchymal malignant tumour of rare vascular origin. Our observation is peculiar by the absence of any prior radiotherapy, its clinical presentation, its morpho-phenotypic characteristics, its management and its evolutive aspects.

     

Correction of Buccal Dehiscence During Immediate Implant Placement Using the Flapless Technique: A Tomographic Evaluation

Background: The aim of this study was to evaluate a new technique for treating dehiscence buccal bone sites (Class II) with immediate implant and collagen‐enriched bovine‐derived xenograft blocks without a surgical flap or membrane. Methods: Individuals with at least 5 mm of buccal bone dehiscence were selected for a flapless surgical approach to insert xenograft blocks into buccal dehiscence defects as well as the gap between implant and residual bone wall. No membrane was used. Buccal bone wall height was measured by computed tomography in the preoperative period (T0) and 6 to 12 months after procedure (T1). Likewise, buccal‐lingual width of alveolar ridge as well as thickness of buccal wall was compared with the contralateral tooth. Results: Fourteen patients were selected. Buccal wall height at T1 was not significantly different after 6 to 12 months between the treated and contralateral teeth, although both were greater than T0 (P <0.01). The heights ranged from 6.4 to 16.30 mm at T0, 12.8 to 25.6 mm at T1, and 14.8 to 25.29 mm in the contralateral teeth. Significant differences were observed between treated teeth (T1) and their contralateral, both buccal‐lingually in the alveolar ridge (P = 0.007) and in buccal wall thickness (P = 0.003). Wall thickness ranged from 0.9 mm to 3.81 mm at T1 and 0.25 mm to 1.60 mm in the contralateral teeth. Conclusion: Immediate implant placement at dehiscence buccal bone sites using flapless surgery combined with xenograft blocks provided complete formation of the buccal bone wall up to the implant shoulder.