Citations

Mathematical models are non-invasive tools used for analyzing biomechanical conditions. Various models of the knee using the finite element analysis technique [1–6] and rigid body spring model (RBSM) [7] have been developed to predict pressure distribution in articulating joints, although the RBSM is considered the simplest of the modeling techniques, while still effectively predicting load distribution. These models can be used to study altered joint loading, which causes a degeneration of the articular cartilage, in order to gain an understanding of the etiology of osteoarthritis (OA). The purpose of this study is to develop a subject-specific analytical knee model using the RBSM approach that incorporates subject-specific geometry, joint health, and loading patterns to predict tibiofemoral load distributions.

We present a case of a young man with severe mucositis following an upper respiratory tract infection limited to the ophthalmic and oral mucosa while sparing the rest of the skin, genitalia and perianal regions. Investigations revealed that the mucositis was a rare extrapulmonary manifestation of Mycoplasma pneumoniae infection. He had progressive vision-threatening symptoms despite antibiotics and best supportive care and thus was treated with intravenous corticosteroids, immunoglobulins, temporary ocular amniotic membrane grafts and tarsorrhaphy. The patient made an almost complete recovery over 6 weeks.

AbstractBackgroundRespiratory syncytial virus (RSV) infections may be fatal in immunocompromised patients. Aerosolized ribavirin is used for treatment, but it is very costly, teratogenic, and inconvenient. We aimed to assess the outcome of oral ribavirin treatment, with or without intravenous immunoglobulin (IVIG), for RSV infections in moderately to severely immunocompromised patients.MethodsMedical records of RSV polymerase chain reaction (PCR)‐positive patients during 2011–2013 were reviewed retrospectively. Eligible patients were moderately to severely immunocompromised and received oral ribavirin (600–800 mg twice daily) with or without IVIG (500 mg/kg q 48 h) as per protocol.ResultsOf 96 adults with PCR‐proven RSV infection, 34 were moderately to severely immunocompromised and received oral ribavirin treatment. The mean age was 56.2 years (range: 18–90); 21 were male. Underlying conditions were hematologic malignancy with or without hematopoietic stem cell transplant (n = 25), lung transplant (n = 3), or receipt of cytotoxic chemotherapy (n = 11). The presenting symptoms were cough (94%), fever (62%), and dyspnea (59%). The most common radiographic findings were patchy and nodular infiltrates and opacities. Of 34 patients, 31 were hospitalized, with 13 admitted to the intensive care unit and 6 required mechanical ventilation. The median absolute lymphocyte count on presentation was 480 cells/mm3. RSV pneumonia developed in 24 patients. The median initial duration of oral ribavirin treatment was 10 days (range: 4–11); 4 patients were re‐treated. Of 34 patients, 19 received a mean of 2.7 doses of IVIG. Two patients had adverse reactions to ribavirin (hemolytic anemia and lactic acidosis in 1 patient, and altered mental status in another). No patient died from RSV infection. Three patients died from complications of their underlying illness; all others recovered clinically.ConclusionsOral ribavirin with or without IVIG is a well‐tolerated treatment for RSV infection in moderately to severely immunocompromised hosts. Comparative prospective studies should ideally be performed to determine if oral ribavirin is the optimal therapy for RSV infection in this patient population.

Free vascular endothelial growth factor (VEGF) is undetectable in plasma during human pregnancy. However, studies examining pregnant rats have reported both low (8–29 pg/ml) and high (527–1,030 pg/ml) free VEGF. These discrepancies cast uncertainty over the use of rat models to study angiogenic factors in pregnancy and preeclampsia. This study investigates methodological factors that may explain these discrepancies. Plasma VEGF in nonpregnant, day 7 pregnant, and day 19 pregnant rats was measured using rat and mouse ELISAs (R&D Systems). The rat ELISA detected VEGF in plasma from nonpregnant rats but not in plasma from day 19 pregnant rats. The mouse ELISA detected higher VEGF concentrations than the rat ELISA in every sample tested. This discrepancy was greater in day 19 pregnant rats (median: 2,273 vs. 0 pg/ml) than in nonpregnant (97 vs. 20 pg/ml) and day 7 pregnant (66 vs. 2 pg/ml) rats. Recovery of recombinant rat VEGF (rrVEGF) spiked into plasma from nonpregnant and day 7 pregnant rats was high for the rat ELISA (82–105%) but low for the mouse ELISA (17–22%). The rat ELISA did not recover rrVEGF in plasma from day 19 pregnant rats, suggesting that this ELISA measures free VEGF. The use of the rat versus mouse ELISA likely explains the differences in reported VEGF concentrations in pregnant rats. While the rat ELISA appears to measure free VEGF, plasma concentrations in nonpregnant and pregnant rats are below the assay sensitivity limit. As most previous studies of pregnant rats used the mouse VEGF ELISA, these data should be interpreted cautiously.

ABSTRACTBackground:The purpose of this study was to identify the frequency of fat‐soluble vitamin deficiencies in children with celiac disease (CD) and to determine the value of routine testing for these deficiencies.Methods:We conducted a retrospective medical record review of patients with a confirmed diagnosis of CD and fat‐soluble vitamin levels measured at diagnosis between 1995 and 2012 at Mayo Clinic. Patients' demographics, fat‐soluble vitamin levels, and pertinent clinical factors at the time of diagnosis were collected.Results:Eighty‐three patients were included in the final analysis: 51 girls and 32 boys, with an average age at diagnosis of 12.8 years in girls and 13.0 years in boys. The most commonly reported symptoms were abdominal pain in 49 patients and diarrhea in 30 patients. Family history of CD was reported in 32 patients. Average vitamin levels for vitamin E, 25‐hydroxyvitamin D (25 (OH) D), and vitamin A were 7.5 mg/L, 32.8 ng/mL, and 334.5 μg/dL, respectively. No patients had vitamin A deficiency, 2 patients had vitamin E deficiency, and 9 patients had mild‐to‐moderate vitamin D deficiency (none had severe deficiency). Both patients with vitamin E deficiency were symptomatic and had complete villous atrophy. Thirty‐one patients had insufficiency of 25 (OH) D, which was less than the reported frequency of vitamin D insufficiency in the general pediatric population in the United States in 2004. None of the patients were receiving vitamin supplements at the time of diagnosis.Conclusions:Fat‐soluble vitamin deficiencies are uncommon in children with new diagnosis of CD. Routine measuring of fat‐soluble vitamins levels may not be necessary.

The main functions of the human musculoskeletal system are to sustain loads and provide mobility. Bones and joints themselves cannot produce movement; skeletal muscles provide the ability to move. Knowledge of muscle forces during given activities can provide insight into muscle mechanics, muscle physiology, musculoskeletal mechanics, neurophysiology, and motor control. However, clinical examinations or instrumented strength testing only provides information regarding muscle groups. Musculoskeletal models are typically needed to calculate individual muscle forces.