Human behavior. Sex equality can explain the unique social structure of hunter-gatherer bands

The social organization of mobile hunter-gatherers has several derived features, including low within-camp relatedness and fluid meta-groups. Although these features have been proposed to have provided the selective context for the evolution of human hypercooperation and cumulative culture, how such a distinctive social system may have emerged remains unclear. We present an agent-based model suggesting that, even if all individuals in a community seek to live with as many kin as possible, within-camp relatedness is reduced if men and women have equal influence in selecting camp members. Our model closely approximates observed patterns of co-residence among Agta and Mbendjele BaYaka hunter-gatherers. Our results suggest that pair-bonding and increased sex egalitarianism in human evolutionary history may have had a transformative effect on human social organization.

Multiple Choice Questions-Part II (Classification, Item Preparation, Analysis and Banking)

No Abstract Available DOI: http://dx.doi.org/10.3126/jucms.v2i3.11830 Journal of Universal College of Medical Sciences Vol.2(3) 2014: 54-59

SMAR1 coordinates HDAC6-induced deacetylation of Ku70 and dictates cell fate upon irradiation

Acetylation status of DNA end joining protein Ku70 dictates its function in DNA repair and Bax-mediated apoptosis. Despite the knowledge of HDACs and HATs that are reported to modulate the acetylation dynamics of Ku70, very little is known about proteins that critically coordinate these key modifications. Here, we demonstrate that nuclear matrix-associated protein scaffold/matrix-associated region-binding protein 1 (SMAR1) is a novel interacting partner of Ku70 and coordinates with HDAC6 to maintain Ku70 in a deacetylated state. Our studies revealed that knockdown of SMAR1 results in enhanced acetylation of Ku70, which leads to impaired recruitment of Ku70 in the chromatin fractions. Interestingly, ionizing radiation (IR) induces the expression of SMAR1 and its redistribution as distinct nuclear foci upon ATM-mediated phosphorylation at serine 370. Furthermore, SMAR1 regulates IR-induced G2/M cell cycle arrest by facilitating Chk2 phosphorylation. Alternatively, SMAR1 provides radioresistance by modulating the association of deacetylated Ku70 with Bax, abrogating the mitochondrial translocation of Bax. Thus, we provide mechanistic insights of SMAR1-mediated regulation of repair and apoptosis via a complex crosstalk involving Ku70, HDAC6 and Bax.

Large-volume blood patch to multiple sites in the epidural space through a single-catheter access site for treatment of spontaneous intracranial hypotension

BACKGROUND AND PURPOSE

Spontaneous intracranial hypotension can be a therapeutic challenge to the treating physician. In this study, we present our experience with the administration of a large-volume blood patch to multiple sites in the epidural space through a single-catheter access site.

MATERIALS AND METHODS

A retrospective review was conducted of patients with spontaneous intracranial hypotension who underwent a large-volume blood patch to multiple sites in the epidural space through a single-catheter access site from 2010 to 2012. Patient demographic data, clinical charts, indications for treatment, radiographic images, procedure notes, and postprocedure hospital course were reviewed.

RESULTS

Overall, 9 patients were identified who underwent 20 blood patch procedures. Patients were selected to undergo the large-volume procedure either because they had a failed site-directed epidural blood patch or if imaging demonstrated multiple possible leak sites. There were 6 women and 3 men, with an average age of 33.5 years. The mean volume of blood injected per procedure was 54.1 mL (median=55 mL; range=38-70 mL). All patients had an orthostatic headache as one of their presenting symptoms; 22% also presented with neurocognitive decline and behavioral changes; 89% of patients had improvement or resolution of their symptoms; and 80% of patients who had a previously failed site-directed epidural blood or fibrin glue patch improved with a large volume catheter-directed blood patch.

CONCLUSIONS

Our experience supports the use of a large-volume blood patch to multiple sites in the epidural space through a single-catheter access site for the treatment of spontaneous intracranial hypotension. Additionally, our results indicate a role for this procedure in refractory cases of spontaneous intracranial hypotension.

Pediatric Precursor B-cell Lymphoblastic Lymphoma Presenting with Extensive Skeletal Lesions

Lymphoblastic lymphoma (LL) of the B cell type is uncommon, and extranodal presentation is even rarer. It is difficult to suspect this diagnosis without clinically obvious lymph nodal mass or bone marrow involvement. A 3-year-old girl presented with progressive pain and swelling of the right knee joint of 3 months duration. Radiograph revealed expansile lytic lesion at the supracondylar area of the right femur; with pathological fracture and multiple lytic areas in both femora. She neither had lymphadenopathy nor organomegaly. Her blood counts, peripheral smear examination and bone marrow examination were normal. Right supracondylar biopsy revealed diagnosis of a precursor B cell LL. Computerized tomography scan revealed a hypodense, poorly enhancing lesion in the left adnexal region. Although rare, precursor B-cell LL may present with extensive bone lesions. Early and accurate diagnosis of this entity is very important due to its high cure rates.

Spinal dural arteriovenous fistulas: clinical experience with endovascular treatment as a primary therapy at 2 academic referral centers

BACKGROUND AND PURPOSE

Spinal dural arteriovenous fistulas are a rare entity that, if left untreated, can lead to considerable morbidity with progressive spinal cord symptoms. The aim of this study was to evaluate the clinical outcome of patients with spinal dural arteriovenous fistulas that were primarily treated with endovascular embolization.

MATERIALS AND METHODS

A retrospective review was performed of all patients from 1997-2010 who underwent treatment at 2 academic referral centers for a spinal dural arteriovenous fistula. Follow-up was performed by clinical examination, and functional status was measured by use of the Aminoff-Logue Disability Scale, McCormick classification grading, and mRS scores. The nonparametric Wilcoxon signed rank test was used to compare pretreatment and posttreatment Aminoff-Logue Disability Scale gait and micturition scores, McCormick classification grading, and mRS scores. P values < .05 were considered significant.

RESULTS

A total of 38 patients were included. Five patients (2 endovascular, 3 surgical) were lost to follow-up and therefore were excluded from the analysis, 29 patients were initially treated from an endovascular approach (9 Onyx, 20 cyanoacrylate), and 4 patients were treated from a standard surgical approach. Five patients in the endovascular group subsequently underwent surgery for various reasons. The clinical improvements in the Aminoff-Logue Disability Scale gait and micturition scores, McCormick classification grading, and the mRS scores were statistically significant (P < .05, Wilcoxon signed rank test).

CONCLUSIONS

We conclude that endovascular treatment of spinal dural arteriovenous fistulas can result in good clinical outcomes. Surgery remains the treatment of choice when safe embolization of the proximal radicular draining vein cannot be obtained or because the shunting artery of the spinal dural arteriovenous fistula also supplies the anterior spinal, posterior spinal, or a radiculomedullary artery.

Nasal endoscopy-evaluation in epistaxis

Epistaxis is generally of two types : one where a cause is recognised ( Local or Systemic ) and the other where the cause is not known. All cases of nose bleeds with no evident cause is customarily categorised into an Idiopathic type. Anterior rhinoscopy ordinarily gives a very limited view of the nose and the probable cause of epistaxis, and this, we feel could he one of the reasons why a proper diagnosis is not always likely. Another problem is the poor localisation of the site of bleeding point. Such cases pose a problem in implementing treatment, as the cause or the site is not easily located. This study tries to venture the exquisite and wide vision provided by the Nasal endoscope. This study also tries to investigate the possibility of reaching the inaccessible bleeding points, to treat them directly. The study was conducted on 60 patients who attended the Out Patient Department and the Indoor ward with complaints of Epistaxis.

Nasal encephalocoele -an atypical case

Nasal encephalocoele present at birth as a characteristic swelling over the nose and widening of intracanthal distance. Atypical nasal encephalocoeles are usually missed at birth due to absence of any external swelling and they present with diagnostic difficulties. These are very rare and present with only an intranasal mass. We report a case of an atypical nasal encephalocnele in a 8 year old boy who presented with a unilateral intranasal mass and cerebrospinal fluid rhinorrhoea.

Genomic impact of cigarette smoke, with application to three smoking-related diseases

There is considerable evidence that inhaled toxicants such as cigarette smoke can cause both irreversible changes to the genetic material (DNA mutations) and putatively reversible changes to the epigenetic landscape (changes in the DNA methylation and chromatin modification state). The diseases that are believed to involve genetic and epigenetic perturbations include lung cancer, chronic obstructive pulmonary disease (COPD), and cardiovascular disease (CVD), all of which are strongly linked epidemiologically to cigarette smoking. In this review, we highlight the significance of genomics and epigenomics in these major smoking-related diseases. We also summarize the in vitro and in vivo findings on the specific perturbations that smoke and its constituent compounds can inflict upon the genome, particularly on the pulmonary system. Finally, we review state-of-the-art genomics and new techniques such as high-throughput sequencing and genome-wide chromatin assays, rapidly evolving techniques which have allowed epigenetic changes to be characterized at the genome level. These techniques have the potential to significantly improve our understanding of the specific mechanisms by which exposure to environmental chemicals causes disease. Such mechanistic knowledge provides a variety of opportunities for enhanced product safety assessment and the discovery of novel therapeutic interventions.

Preliminary experience with the percutaneous embolization of juvenile angiofibromas using only ethylene-vinyl alcohol copolymer (Onyx) for preoperative devascularization prior to surgical resection

BACKGROUND AND PURPOSE

Juvenile angiofibromas are hypervascular tumors that may benefit from preoperative devascularization to reduce intraoperative blood loss. Our purpose was to evaluate the extent of angiographic devascularization and intraoperative blood loss by using only Onyx for percutaneous juvenile angiofibroma tumor embolization.

MATERIALS AND METHODS

We reviewed the clinical records and preoperative and postoperative imaging studies of a consecutive series of 9 patients with juvenile angiofibromas who were treated with preoperative embolization with direct percutaneous injection of Onyx followed by resection from a standard open surgical or endoscopic approach.

RESULTS

Two Fisch type I, 1 Fisch type II, 5 Fisch type IIIa, and 1 Fisch type IVa tumor were treated. Complete devascularization was achieved in all cases percutaneously with only Onyx. There were no complications. The average intraoperative blood loss was 567.7 mL (range, 10-1700 mL). An average of 2.2 needles (range, 1-5 needles) was placed into the tumor. An average of 14.6 mL of Onyx (range, 2-25 mL) was injected into each tumor. Four Fisch type IIIa tumors were removed completely from only an ENE approach.

CONCLUSIONS

Presurgical direct percutaneous embolization of a juvenile angiofibroma with only EVOH before surgical resection is safe and feasible. Our preliminary experience suggests that Onyx may offer a higher degree of devascularization compared with other embolic agents. This may facilitate an easier surgical resection with lower blood loss.

Acute life-threatening hemorrhage in patients with head and neck cancer presenting with carotid blowout syndrome: follow-up results after initial hemostasis with covered-stent placement

BACKGROUND AND PURPOSE

CSP in patients with HNC presenting with CBS can provide immediate hemostasis to prevent exsanguination. We evaluated the safety and efficacy of CSP to control acute life-threatening hemorrhage in patients with HNC presenting with CBS.

MATERIALS AND METHODS

We retrospectively reviewed 10 patients (7 men, 3 women; mean age, 59 years) with HNC presenting with acute life-threatening hemorrhage from CBS that was treated with CSP. We studied patient demographics, presentations, procedures, initial and delayed complications, and technical and clinical outcomes on follow-up.

RESULTS

All patients achieved immediate hemostasis following CSP. Periprocedural complications consisted of groin hematomas (n=2), acute limb ischemia requiring thrombectomy, and an asymptomatic temporal lobe hemorrhage. Imaging and clinical follow-up were available for a mean of 17.7 months (range, 1-60 months). Two patients remained asymptomatic with a patent stent and no evidence of rebleeding at 17 and 21 months, respectively. Recurrent hemorrhages requiring retreatment were encountered in 3 patients secondary to stent infections (30%) at mean duration of 8 months. Neurologic morbidity resulted from stent thrombosis and stroke at 8 months in a single patient. Mortality was unrelated to CSP but was a result of palliative hospice care (n=3) at a mean of 2 months or natural disease progression (n=1) with documented patency of the stent at 6 months.

CONCLUSIONS

Acute life-threatening hemorrhage from CBS related to advanced HNC can be safely and effectively treated with CSP. However, potential delayed ischemic or infectious complications are common in the exposed or infected neck.

Decreased glucose tolerance and plasma adiponectin:resistin ratio in a mouse model of post-traumatic stress disorder

AIMS/HYPOTHESIS

Obesity and type 2 diabetes are among the most serious health pathologies worldwide. Stress has been proposed as a factor contributing to the development of these health risk factors; however, the underlying mechanisms that link stress to obesity and diabetes need to be further clarified. Here, we study in mice how chronic stress affects dietary consumption and how that relationship contributes to obesity and diabetes.

METHODS

C57BL/6J mice were subjected to chronic variable stress (CVS) for 15 days and subsequently fed with a standard chow or high-fat diet. Food intake, body weight, respiratory quotient, energy expenditure and spontaneous physical activity were measured with a customised calorimetric system and body composition was measured with nuclear magnetic resonance. A glucose tolerance test was also applied and blood glucose levels were measured with a glucometer. Plasma levels of adiponectin and resistin were measured using Lincoplex kits.

RESULTS

Mice under CVS and fed with a high-fat diet showed impaired glucose tolerance associated with low plasma adiponectin:resistin ratios.

CONCLUSIONS/INTERPRETATION

This study demonstrates, in a novel mouse model, how post-traumatic stress disorder enhances vulnerability for impaired glucose metabolism in an energy-rich environment and proposes a potential adipokine-based mechanism.