Blunt aortic trauma in a patient with the Ehlers-Danlos syndrome type VI.

A 24-year-old male with the Ehlers-Danlos syndrome (EDS) type VI (ocular scoliotic) who was kicked in the abdomen presented to the emergency room (ER) with abdominal pain. He was found to have a blunt traumatic aortic injury. The patient was treated nonoperatively. He was stable and discharged home on the eighth day. The patient returned to the ER several days later hypotensive and tachycardic. The patient was taken immediately to the operating room, but vascular repair was not possible. The patient expired. We discuss the challenges of taking care of a patient with EDS and offer suggestions that might improve future patient's outcome.

Clinical factors associated with weight loss outcomes after Roux-en-Y gastric bypass surgery.

OBJECTIVE: Gastric bypass surgery is an effective therapy for extreme obesity. However, substantial variability in weight loss outcomes exists that remains largely unexplained. Our objective was to determine whether any commonly collected preoperative clinical variables were associated with weight loss following Roux-en-Y gastric bypass (RYGB) surgery. METHODS: The analysis was based on a prospectively recruited observational cohort of 2,365 patients who underwent Roux-en-Y gastric bypass surgery from 2004 to 2009. Weight loss was stratified into three major phases, early (0-6 months), nadir, and long-term (>36 months). Multivariate regression models were constructed using a database of over 350 variables. RESULTS: A total of 12-14 preoperative variables were independently associated (P < 0.05) with each of the temporal weight loss phases. Preoperative variables associated with poorer nadir and long-term weight loss included higher baseline BMI, higher preoperative weight loss, iron deficiency, use of any diabetes medication, nonuse of bupropion medication, no history of smoking, age >50 years, and the presence of fibrosis on liver biopsy. CONCLUSIONS: Several variables previously associated with poorer weight loss after RYGB surgery including age, baseline BMI, and type 2 diabetes were replicated. Several others suggest possible clinical interventions for postoperative management of RYGB patients to improve weight loss outcomes.

A large mediastinal mass in a 33 year old patient.

Mediastinal masses are commonly found during the evaluation of other illnesses. During gynecologic evaluation for suspected endometriosis, a large asymptomatic intrathoracic mass was discovered in the patient presented. After pre-operative evaluation, the patient underwent thoracotomy with removal of a mature, cystic teratoma invading the pericardium. Invasion of the pericardium is rarely seen with these lesions. The diagnosis of teratoma is difficult to make based solely on radiologic or clinical findings and must be confirmed at pathology for final diagnosis.

Modulation of Kir4.2 rectification properties and pHi-sensitive run-down by association with Kir5.1.

Inwardly rectifying K+ channels (Kir) comprise seven subfamilies that can be subdivided further on the basis of cytosolic pH (pHi) sensitivity, rectification strength and kinetics, and resistance to run-down. Although distinct residues within each channel subunit define these properties, heteromeric association with other Kir subunits can modulate them. We identified such an effect in the wild-type forms of Kir4.2 and Kir5.1 and used this to further understand how the functional properties of Kir channels relate to their structures. Kir4.2 and a Kir4.2-Kir5.1 fusion protein were expressed in HEK293 cells. Inward currents from Kir4.2 were stable over 10 min and pHi-insensitive (pH 6 to 8). Conversely, currents from Kir4.2-Kir5.1 exhibited a pHi-sensitive run-down at slightly acidic pHi. At pHi 7.2, currents in response to voltage steps positive to EK were essentially time independent for Kir4.2 indicating rapid block by Mg2+. Coexpression with Kir5.1 significantly increased the blocking time constant, and increased steady-state outward current characteristic of weak rectifiers. Recovery from blockade at negative potentials was voltage dependent and 2 to 10 times slower in the homomeric channel. These results show that Kir5.1 converts Kir4.2 from a strong to a weak rectifier, rendering it sensitive to pHi, and suggesting that Kir5.1 plays a role in fine-tuning Kir4.2 activity.