Inhaled nitric oxide reverses cell-free hemoglobin-induced pulmonary hypertension and decreased lung compliance. Preliminary results

Background

In order to test the hypothesis that inhaled nitric oxide (NO) reverses the pulmonary hypertension induced by αα-diaspirin crosslinked hemoglobin (ααHb), were studied anesthetized pigs that were administered with a total dose of 200 mg/kg of 10% ααHb. Inhaled NO (5 ppm) was administered for 10 min, and then discontinued for 10 min. This cycle was then repeated with 10 ppm inhaled NO.

Results

ααHb caused pulmonary arterial pressure (PAP) to increase from 27 ± 1.7 to 40 ± 3.0 mmHg (P<0.05) and dynamic lung compliance to decrease from 29± 1.5 to 23± 1.6 ml/cmH₂O (P < 0.05). After both doses of inhaled NO, but particularly 10 ppm, PAP was reduced (P < 0.05) and lung compliance increased (P < 0.05) from the ααHb levels. When inhaled NO was discontinued PAP again increased and lung compliance decreased to levels significantly different from baseline (P < 0.05).

Conclusion

We conclude that cell-free hemoglobin-induced pulmonary hypertension and decreased lung compliance can be selectively counteracted by inhaled NO.     

Novel oncogene and tumor suppressor mutations in KIT and PDGFRA wild type gastrointestinal stromal tumors revealed by next generation sequencing

Among gastrointestinal stromal tumors (GISTs) of 10–15% are negative for KIT and PDGFRA, and most of these cases are SDH deficient. Recent studies have provided data on additional molecular alterations such as KRAS in KIT mutant GISTs. We aimed to assess the frequency and spectrum of somatic mutations in common oncogenes as well as copy number variations in GISTs negative for KIT and PDGFRA mutations. GISTs with wild type KIT/PDGFRA were tested via next generation sequencing for somatic mutations in 341 genes. SDHB immunohistochemistry to evaluate for SDH deficiency was also performed. Of 267 GISTs tested for KIT and PDGFRA mutations, 15 were wild type, of which eight cases had material available for further testing. All eight cases had loss of SDHB expression and had various molecular alterations involving ARID1A, TP53, and other genes. One case had a KRAS G12V (c.35G>T) mutation in both the primary gastric tumor and a post‐imatinib recurrence. This tumor had anaplastic features and was resistant to multiple tyrosine kinase inhibitors, ultimately resulting in cancer‐related mortality within 2 years of diagnosis. In conclusion, KRAS mutations occur in rare GISTs with wild type KIT and PDGFRA. These tumors may display immunohistochemical positivity for KIT and primary resistance to tyrosine kinase inhibitors. © 2014 Wiley Periodicals, Inc.     

THE EFFECT OF CULTURAL FACTORS ON DAILY COPING AND INVOLUNTARY RESPONSES TO STRESS AMONG LOW‐INCOME LATINO ADOLESCENTS

This study used daily diary methodology to examine associations between cultural factors and daily coping and responses to stress among predominantly low‐income Latino adolescents. A total of 58 middle school students (53% male, mean age = 13.31, 95% Latino) completed baseline measures assessing demographic characteristics, familism, ethnic identity, and family ethnic socialization. They subsequently completed 7 consecutive daily diaries assessing daily stress, coping, and involuntary stress responses. Results yielded main effects of stress, gender, familism, and ethnic identity on adolescents’ coping and involuntary stress responses. In addition, interactions between stress and familism, ethnic identity, and family ethnic socialization emerged. Results suggest that familism may promote adaptive responses to stress, while adolescents who report more family ethnic socialization may rely more on maladaptive responses at high levels of stress. Findings related to ethnic identity were mixed and varied depending on levels of ethnic identity exploration versus commitment.     

Mercury biomarkers and DNA methylation among michigan dental professionals

Modification of the epigenome may be a mechanism underlying toxicity and disease following chemical exposure. Animal and human data suggest that mercury (Hg) impacts DNA methylation. We hypothesize that methylmercury and inorganic Hg exposures from fish consumption and dental amalgams, respectively, may be associated with altered DNA methylation at global repetitive elements (long interspersed elements, LINE‐1) and candidate genes related to epigenetic processes (DNMT1) and protection against Hg toxicity (SEPW1, SEPP1). Dental professionals were recruited at Michigan Dental Association (MDA) meetings in 2009 and 2010. Subjects (n = 131) provided survey data (e.g. exposure sources, demographics) and biological samples for Hg measurement and epigenetic analysis. Total Hg was quantified via atomic absorption spectrophotometry in hair and urine, indicative of methylmercury and inorganic Hg exposures, respectively. Global repetitive and candidate gene methylation was quantified via pyrosequencing of bisulfite converted DNA isolated from buccal mucosa. Hair Hg (geometric mean (95% CI): 0.37 (0.31–0.44) µg/g) and urine Hg (0.70 (0.60–0.83) µg/L) were associated with sources of exposure (fish consumption and dental amalgams, respectively). Multivariable linear regression revealed a trend of SEPP1 hypomethylation with increasing hair Hg levels, and this was significant (P < 0.05) among males. The trend remained when excluding non‐dentists. No significant relationships between urine Hg and DNA methylation were observed. Thus, in a limited cohort, we identified an association between methylmercury exposure and hypomethylation of a potentially labile region of the genome (SEPP1 promoter), and this relationship was gender specific. Environ. Mol. Mutagen. 54:195–203, 2013. © 2013 Wiley Periodicals, Inc.     

Genetic polymorphisms and traumatic brain injury: the contribution of individual differences to recovery

Recovery after Traumatic Brain Injury (TBI) is variable, even for patients with similar severity of brain injury. Recent research has highlighted the contribution that genetic predisposition plays in determining TBI outcome. This review considers the potential for genetic polymorphisms to influence recovery of cognitive and social processes following TBI. Limitations and considerations that researchers should make when assessing the potential impact of polymorphisms on TBI outcome are also discussed. Understanding the genetic factors that support neuroplasticity will contribute to an understanding of the variation in outcome following injury and help to identify potential targets for rehabilitation.     

Diagnosis and treatment of sudden-onset sensorineural hearing loss: a study of 51 patients.

OBJECTIVE: The study purpose was to determine the efficacy of steroid and antiviral therapy in the management of idiopathic sudden sensorineural hearing loss (SSNHL). STUDY DESIGN AND SETTING: We conducted a retrospective study of patients presenting to an academic tertiary care center. Fifty-one patients were evaluated. All patients were placed on the same treatment protocol. RESULTS: Thirty-seven patients (73%) had recovery of hearing. Ninety-one percent of patients with vertigo and all patients with mid-frequency hearing loss and up-sloping hearing loss recovered with treatment (P < 0.05). Recovery was significantly related to age, onset of hearing loss, and audiogram type; however outcome was not significantly related to gender, vertigo, tinnitus, or laterality (P < 0.05). CONCLUSION: Our treatment protocol produced a recovery rate, which exceeds the spontaneous recovery rate. Unlike prior studies, all patients with up-sloping and mid-frequency SSNHL had recovery. In addition, vertigo did not indicate a poor prognosis. SIGNIFICANCE: Antiviral therapy and increased length of steroid treatment may play a role in the improved recovery rates.     

Temporal Trends in the Use of Acute Recanalization Therapies for Ischemic Stroke in Patients with Cancer

Objective: We sought to characterize the US nationwide temporal trends in recanalization therapy utilization for ischemic stroke among patients with and without cancer. Methods: We identified all acute ischemic stroke (AIS) hospitalizations in the National Inpatient Sample from January 1, 1998 to September 30, 2015. The primary exposure was solid or hematologic cancer. The primary outcome was use of intravenous thrombolysis. The secondary outcome was use of endovascular therapy (EVT). Results: Among 9,508,804 AIS hospitalizations, 503,510 (5.3%) involved cancer patients. Intravenous thrombolysis use among ischemic stroke patients with cancer increased from .01% (95% confidence interval [CI], .00%-.02%) in 1998 to 4.91% (95% CI, 4.33%-5.48%) in 2015, whereas intravenous thrombolysis use among ischemic stroke patients without cancer increased from .02% (95% CI, .01%-.02%) in 1998 to 7.22% (95% CI, 6.98%-7.45%) in 2015. The demographic- and comorbidity-adjusted odds ratio/year of receiving intravenous thrombolysis was similar in patients with cancer (1.21; 95% CI, 1.20-1.23) versus those without (1.20; 95% CI, 1.19-1.21). EVT use among ischemic stroke patients with cancer increased from .05% (95% CI, .02%-.07%) in 2006 to 1.90% (95% CI, 1.49%-2.31%) in 2015, whereas EVT use among ischemic stroke patients without cancer increased from .09% (95% CI, .00%-.18%) in 2006 to 1.88% (95% CI, 1.68%-2.09%) in 2015. Conclusions: Among 9.5 million AIS hospitalizations, patients with cancer received intravenous thrombolysis about two thirds as often as patients without cancer. This difference persisted over time despite increased utilization in both groups. EVT utilization was similar between cancer and non–cancer AIS patients.     

Mycobacterial pseudotumor of the plantar fascia: how common is it?

Mycobacterial spindle cell pseudotumor (MSCP) is an extremely rare complication of mycobacterial infections. It has been reported to occur in various sites such as skin, lymph nodes, bone marrow, lungs, and spleen. This tumor-like lesion can be confused clinically as well as radiographically with dermatofibroma, nodular fasciitis, xanthogranuloma, and Kaposi's sarcoma.While this lesion is rare and has been previously reported to occur only in superficial skin, we emphasize its consideration and inclusion in the differential diagnoses when a deep soft tissue mass is complicated by symptoms of deep tissue infection secondary to abscess formation in immunocompromised hosts. Here, we present the clinical and radiologic findings of a case of MSCP involving the deep plantar sheaths.