Biomechanical evaluation of different types of rigid internal fixation techniques for subcondylar fractures.

PURPOSE: The aim of this study was to evaluate the biomechanical stability of various internal fixation systems for subcondylar fractures. MATERIALS AND METHODS: Eighteen identical synthetic mandibles were used. Left condylar processes were cut to mimic perpendicular subcondylar fracture and right sides were mimicked oblique subcondylar fracture. The fixation systems used included single 4-hole mini adaptation plate, double fixation with the same plates, single 4-hole mini dynamic compression plate (DCP), Eckelt lag screw system, Wurzburg lag screw plate system and double 4-hole biodegradable miniplates made of poly L-lactide (PLLA). In oblique fractures, one of the screws fixing plates was used bicortically through bone fragments. The loading vector simulated physiologic forces to the condyle on biting with servohydraulic testing machine until failure was reached. Load-displacement curve, maximum load for failure, and stiffness were measured. RESULTS: In perpendicular fracture, double adaptation plate showed the highest level of tolerance load followed by Eckelt lag and double PLLA plate. In stiffness, double adaptation plate and Eckelt lag screw showed higher level of stiffness, whereas double PLLA was almost at the same level of single DCP. In oblique fracture, double adaptation plate showed the highest strength. CONCLUSIONS: In this laboratory setting, double adaptation plates fixation proved to have superior biomechanical stability in both fracture conditions. Eckelt lag screw showed good stability in the perpendicular fracture, however, it was weak in the oblique fracture.     

Hypercalcemia associated with parathyroid hormone-related protein at the terminal stage of uncomplicated squamous cell carcinoma in the head and neck region.

BACKGROUND: Parathyroid hormone-related protein (PTHrP) is mainly responsible for hypercalcemia in squamous cell carcinomas (SCCs). METHODS: We retrospectively checked the appearance of hypercalcemia among 33 patients who died with head and neck SCC. Serum concentrations of C-terminal region of PTHrP (C-PTHrP) were measured in 15 of them. The intracellular PTHrP expression was immunohistochemically stained in 42 SCC sections obtained from the 33 before the appearance of hypercalcemia. RESULTS: Hypercalcemia appeared in 24 of the 33, and increased serum C-PTHrP levels were confirmed in 11 of 12 hypercalcemic patients. PTHrP was identified in all SCC sections, and a stronger intensity than in normal squamous epithelia was observed in 50% of those obtained within 1 year before the onset of hypercalcemia. CONCLUSION: A high incidence of PTHrP-induced hypercalcemia was shown among patients dying with head and neck SCCs. The intracellular increase in PTHrP might be observed preceding hypercalcemia.     

Therapy with hypertonic saline in combination with anti-convulsants for hyponatremia-induced seizure: a case report and review of the literature

Seizures are an uncommon but serious complication of hyponatremia which can lead to permanent brain damage and even death. It is recommended that patients with hyponatremic-induced seizures be treated with 3% hypertonic saline, however, a rapid rate of correction may result in central pontine myelinolysis (CPM), a severe neurological disorder characterized by mutism, dysarthria, spastic quadriparesis, and pseudobulbar palsy. The patient in this case developed a hyponatremia-induced generalized tonic-clonic seizure which was aborted by rapid therapy with diazepam, followed by hypertonic saline and phenytoin. Subsequent replacement of hypertonic saline with normal saline and salt tabs in combination with phenytoin allowed gradual correction of serum sodium without any subsequent seizures or neurological complications.     

Hyponatremia associated with sertraline and fluoxetine: a case report

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) is a rare but serious adverse effect of the selective serotonin reuptake inhibitors (SSRIs). Although many case reports describe this association, few report the effect of rechallenge with another SSRI. We present a case of an elderly patient who developed hyponatremia with sertraline and SIADH when rechallenged with fluoxetine.     

Tracheal agenesis: a case report

Tracheal agenesis is a rare congenital anomaly which results inevitably in immediate respiratory distress after delivery. Since the first report of the case in 1900, more than 150 cases reported in the Japanese and world literature. Attempts to save these children have failed to permit survival although a slight prolongation of life was achieved in some. We treated a baby girl with tracheal agenesis associated with other multiple anomalies and surgical intervention was attempted but without success due to incorrectable anatomy. Herein we describe her clinical picture and autopsy findings. Along with a review of the Japanese literature, we discuss this rare anomaly in terms of its anatomy, associated anomalies, pathogenesis, and clinical management.     

A novel method to quantify calcium response pattern and oscillation using fura2 and acridine orange

To study calcium imaging data of cell populations that have various response patterns in peak amplitude and frequency of calcium oscillation in response to stimulation, comprehensive characterization based on statistical analysis of each response is important. In cultures of cells that are flat and in contact with each other, it is difficult to distinguish individual cells in calcium imaging data. We have developed a novel method to determine areas corresponding to individual cells in calcium imaging data. Rat neonatal cerebral astrocytes were filled with the calcium indicator Fura2, stained with acridine orange, and illuminated with UV light. The cell nuclei were clearly visualized. In addition, the images of these nuclei were useful for analyzing concentration-dependent alteration of calcium oscillation of cultured astrocytes in response to glutamate. This novel method may be useful for studying factors affecting calcium response patterns of cultured cell populations, including culture conditions, stimulus paradigms, and synthetic compounds.     

Acute generalized pustular psoriasis presenting with erythroderma associated with shock and acute renal failure

Acute generalized pustular psoriasis is an uncommon but dangerous form of psoriasis with a systemic presentation. Acute exacerbation, an early picture of acute generalized pustular psoriasis (AGPP), can be fatal, therefore, early recognition and systemic therapy is critical. It is an important differential diagnosis of erythroderma. Epidemiology, etiology, diagnosis, and treatment options are discussed in this paper.