Morphological variations in the basioccipital region of the South Indian skull

Background: The craniovertebral junction is a transitional region of spine that exhibits extensive structural variability. Variations of basiocciput are of interest for anatomists and clinicians because they produce clinical symptoms or lead to misinterpretations of radiological images.Materials and Methods: The study was conducted on 202 dry human skull bone (12 occipital bone and crania 190) belonging to south Indian population for variations of basiocciput over a period of six years.Results: Prevalence of hyperostotic variants was significantly higher than hypostotic variants in present study. Most common type observed was of precondylar tubercle (2.48%) followed by fossa navicularis (1.49). The prevalence of other variations such as prebasioccipital arch, third occipital condyle, exostosis and basioccipital cleft was similar (0.5%) in the study population.Conclusions: These cranio-vertebral anomalies will be useful not only to anatomists, radiologists and surgeons while dealing with base of the skull and basiocciput in particular but also to study anthropological significance and may guide the future researchers in comparative human anatomy.Nepal Journal of Medical Sciences Vol.3(2) 2014: 124-128

Intravenous immunoglobulin treatment preserves and protects primary rat hippocampal neurons and primary human brain cultures against oxidative insults

Alzheimer's disease (AD) is characterized by deleterious accumulation of amyloid-β (Aβ) peptide into senile plaque, neurofibrillary tangles formed from hyperphosphorylated tau protein, and loss of cholinergic synapses in the cerebral cortex. The deposition of Aβ-loaded plaques results in microglial activation and subsequent production of reactive oxygen species (ROS), including free radicals. Neurons in aging and AD brains are particularly vulnerable to ROS and other toxic stimuli. Therefore, agents that decrease the vulnerability of neurons against ROS may provide therapeutic values for the treatment or prevention of AD. In the present study, our goal was to test whether intravenous immunoglobulin (IVIG) treatment could preserve as well as protect neurons from oxidative damage. We report that treatment with IVIG protects neuronal viability and synaptic proteins in primary rat hippocampal neurons. Further, we demonstrate the tolerability of IVIG treatment in the primary human fetal mixed brain cultures. Indeed, a high dose (20 mg/ml) of IVIG treatment was well-tolerated by primary human brain cultures that exhibit a normal neuronal phenotype. We also observed a potent neuropreservatory effect of IVIG against ROS-mediated oxidative insults in these human fetal brain cultures. These results indicate that IVIG treatment has great potential to preserve and protect primary human neuronal-enriched cultures and to potentially rescue dying neurons from oxidative insults. Therefore, our findings suggest that IVIG treatment may represent an important therapeutic agent for clinical trials designed to prevent and delay the onset of neurodegeneration as well as AD pathology.

Leveraging an Electronic Health Record-Linked Biorepository to Generate a Metformin Pharmacogenomics Hypothesis

Metformin is a first-line antihyperglycemic agent commonly prescribed in type 2 diabetes mellitus (T2DM), but whose pharmacogenomics are not clearly understood. Further, due to accumulating evidence highlighting the potential for metformin in cancer prevention and treatment efforts it is imperative to understand molecular mechanisms of metformin. In this electronic health record(EHR)-based study we explore the potential association of the flavin-containing monooxygenase(FMO)-5 gene, a biologically plausible biotransformer of metformin, and modifying glycemic response to metformin treatment. Using a cohort of 258 T2DM patients who had new metformin exposure, existing genetic data, and longitudinal electronic health records, we compared genetic variation within FMO5 to change in glycemic response. Gene-level and SNP-level analysis identified marginally significant associations for FMO5 variation, representing an EHR-driven pharmacogenetics hypothesis for a potential novel mechanism for metformin biotransformation. However, functional validation of this EHR-based hypothesis is necessary to ascertain its clinical and biological significance.

Impact of acamprosate on plasma amyloid-β precursor protein in youth: a pilot analysis in fragile X syndrome-associated and idiopathic autism spectrum disorder suggests a pharmacodynamic protein marker

BACKGROUND

Understanding of the pathophysiology of autism spectrum disorder (ASD) remains limited. Brain overgrowth has been hypothesized to be associated with the development of ASD. A derivative of amyloid-β precursor protein (APP), secreted APPα (sAPPα), has neuroproliferative effects and has been shown to be elevated in the plasma of persons with ASD compared to control subjects. Reduction in sAPPα holds promise as a novel molecular target of treatment in ASD. Research into the neurochemistry of ASD has repeatedly implicated excessive glutamatergic and deficient GABAergic neurotransmission in the disorder. With this in mind, acamprosate, a novel modulator of glutamate and GABA function, has been studied in ASD. No data is available on the impact of glutamate or GABA modulation on sAPPα function.

METHODS

Plasma APP derivative levels pre- and post-treatment with acamprosate were determined in two pilot studies involving youth with idiopathic and fragile X syndrome (FXS)-associated ASD. We additionally compared baseline APP derivative levels between youth with FXS-associated or idiopathic ASD.

RESULTS

Acamprosate use was associated with a significant reduction in plasma sAPP(total) and sAPPα levels but no change occurred in Aβ40 or Aβ42 levels in 15 youth with ASD (mean age: 11.1 years). Youth with FXS-associated ASD (n = 12) showed increased sAPPα processing compared to age-, gender- and IQ-match youth with idiopathic ASD (n = 11).

CONCLUSIONS

Plasma APP derivative analysis holds promise as a potential biomarker for use in ASD targeted treatment. Reduction in sAPP (total) and sAPPα may be a novel pharmacodynamic property of acamprosate. Future study is required to address limitations of the current study to determine if baseline APP derivative analysis may predict subgroups of persons with idiopathic or FXS-associated ASD who may respond best to acamprosate or to potentially other modulators of glutamate and/or GABA neurotransmission.

Excision of a giant anterior chest wall neurofibroma and chest wall reconstruction with methlymethacrylate and vertical rectus abdominis musculocutaneous flap: case report

INTRODUCTION

Plexiformneurofibromas (PNFs) are benign nerve tumours resulting from aberrant growth of cells of nerve sheath. PNFs are generally painless, slow growing neoplasms. Although most neoplasms are asymptomatic, they can be particularly debilitating due to their potential to grow to very large sizes. They have potential for transformation into highly malignant peripheral nerve sheath tumours which occur in approximately 5% of patients. They can affect most parts of the body. When they occur in the chest wall, they are amenable to excision. Following excision, a surgeon is faced with a large skeletal and soft tissue defects which pose functional and cosmetic challenges.

CASE PRESENTATION

We present a 24-year-old farmer that presented with a giant anterior chest wall plexiformneurofibroma that was noticed since childhood. He had excision of the mass and skeletal reconstruction with methylmethacrylate sandwiched in prolene mesh and softtissue coverage with vertical rectus abdominismusculocutaneous flap.

CONCLUSION

We conclude that the use of methylmethacrylate and myocutaneous flaps give both good functional and cosmetic outcome following excision of large chest wall tumours.

Human primary mixed brain cultures: preparation, differentiation, characterization and application to neuroscience research

BACKGROUND

Culturing primary cortical neurons is an essential neuroscience technique. However, most cultures are derived from rodent brains and standard protocols for human brain cultures are sparse. Herein, we describe preparation, maintenance and major characteristics of a primary human mixed brain culture, including neurons, obtained from legally aborted fetal brain tissue. This approach employs standard materials and techniques used in the preparation of rodent neuron cultures, with critical modifications.

RESULTS

This culture has distinct differences from rodent cultures. Specifically, a significant numbers of cells in the human culture are derived from progenitor cells, and the yield and survival of the cells grossly depend on the presence of bFGF. In the presence of bFGF, this culture can be maintained for an extended period. Abundant productions of amyloid-β, tau and proteins make this a powerful model for Alzheimer's research. The culture also produces glia and different sub-types of neurons.

CONCLUSION

We provide a well-characterized methodology for human mixed brain cultures useful to test therapeutic agents under various conditions, and to carry forward mechanistic and translational studies for several brain disorders.

Addictions and stress: clues for cocaine pharmacotherapies

Addictions are chronic relapsing brain diseases, with behavioral manifestations. Three main factors contribute to the development of an addiction: environment, including stress, the reinforcing effects of the drug, and genetics. In this review we will discuss the involvement of the dysregulation of the stress responsive hypothalamic-pituitary-adrenal (HPA) axis in the acquisition of, and persistence to drug addiction (Section B). Addictions to specific drugs such as cocaine/psychostimulants, alcohol, and mu-opioid receptor agonists (e.g., heroin) have some common direct or downstream effects, including modulation of dopaminergic systems. Through its action on the dopaminergic signaling pathways, cocaine affects the HPA axis, and brain nuclei responsible for movements, and rewarding effects. Several neurobiological systems have been implicated with cocaine addiction, including dopamine, serotonin and glutamate systems, opioid receptor and opioid neuropeptide gene systems, stress-responsive systems including CRF, vasopressin and orexin. The use of animal models (Sections C and D) has been essential for studying the individual vulnerabilities to the effects of drugs of abuse and the neural pathways and neurotransmitters affected by these drugs. Basic clinical research has revealed important relationship between cocaine use, HPA axis responsiveness, and gender (Section E). Finally, we will discuss gene polymorphisms that are associated with drug use (Section F). Results from animal models and basic clinical research have shown important interactions between the dopaminergic and the opioid systems. Hence, compounds modulating the opioid system may be beneficial in treating cocaine addiction.

Intravenous immunoglobulin (IVIG) treatment exerts antioxidant and neuropreservatory effects in preclinical models of Alzheimer's disease

Intravenous immunoglobulin (IVIG) has shown limited promise so far in human clinical studies on Alzheimer's disease (AD), yet overwhelmingly positive preclinical work in animals and human brain cultures support the notion that the therapy remains potentially efficacious. Here, we elaborate on IVIG neuropreservation by demonstrating that IVIG protects human primary neurons against oxidative stress in vitro and that IVIG preserves antioxidant defense mechanisms in vivo. Based on these results, we propose the following translational impact: If the dosage and treatment conditions are adequately optimized, then IVIG treatment could play a significant role in preventing and/or delaying the progression of neurodegenerative diseases, such as AD. We suggest that IVIG warrants further investigation to fully exploit its potential as an anti-oxidant, neuroprotective and synapto-protecting agent.

Efficacy and toxicity of clioquinol treatment and A-beta42 inoculation in the APP/PSI mouse model of Alzheimer's disease

Alzheimer's disease (AD), the most common human neurodegenerative disease, is characterized pathologically by numerous deposits of amyloid plaques in the brain. Systemic administration of clioquinol (CQ) and inoculation with amyloid-beta42 (Aβ42) vaccines have been demonstrated to significantly inhibit deposits of amyloid in AD brains. However, each of these treatments has also been reported to be neurotoxic. The generation of transgenic mice models of AD has made it possible to study aspects of this disease employing experimental animals. In the present study, we investigated the efficacy and toxicity of CQ and Aβ42 vaccine in a transgenic AD (APP/PS1) mouse model. Our results confirmed that both CQ and Aβ42 vaccine were effective in significantly reducing the deposits of amyloid in the brains of transgenic AD mice. We also report here that systemic CQ induces myelinopathies in the dorsal lateral geniculate nucleus (DLG), which was almost devoid of amyloid plaques and is the primary site of retinal efferent projections via the optic nerve. This is the first report that systemic administration of CQ causes myelinopathies in the central nervous system (CNS) of a transgenic AD mouse model as well as wild-type mice. Inoculation with an Aβ42 vaccine was also found, for the first time, to result in a significant increase in plaque-independent astrocytic hyperplasia in the dorsal part of the lateral septal nucleus (LSD) which was also devoid of plaques, reflecting potential brain inflammatory processes.

MicroRNA-339-5p down-regulates protein expression of β-site amyloid precursor protein-cleaving enzyme 1 (BACE1) in human primary brain cultures and is reduced in brain tissue specimens of Alzheimer disease subjects

Alzheimer disease (AD) results, in part, from the excess accumulation of the amyloid-β (Aβ) peptide as neuritic plaques in the brain. The short Aβ peptide is derived from the large transmembrane Aβ precursor protein (APP). The rate-limiting step in the production of Aβ from APP is mediated by the β-site APP-cleaving enzyme 1 (BACE1). Dysregulation of BACE1 levels leading to excess Aβ deposition is implicated in sporadic AD. Thus, elucidating the full complement of regulatory pathways that control BACE1 expression is key to identifying novel drug targets central to the Aβ-generating process. MicroRNAs (miRNAs) are expected to participate in this molecular network. Here, we identified a known miRNA, miR-339-5p, as a key contributor to this regulatory network. Two distinct miR-339-5p target sites were predicted in the BACE1 3'-UTR by in silico analyses. Co-transfection of miR-339-5p with a BACE1 3'-UTR reporter construct resulted in significant reduction in reporter expression. Mutation of both target sites eliminated this effect. Delivery of the miR-339-5p mimic also significantly inhibited expression of BACE1 protein in human glioblastoma cells and human primary brain cultures. Delivery of target protectors designed against the miR-339-5p BACE1 3'-UTR target sites in primary human brain cultures significantly elevated BACE1 expression. Finally, miR-339-5p levels were found to be significantly reduced in brain specimens isolated from AD patients as compared with age-matched controls. Therefore, miR-339-5p regulates BACE1 expression in human brain cells and is most likely dysregulated in at least a subset of AD patients making this miRNA a novel drug target.

Morphology of the superior gluteal nerve: a study in adult human cadavers

The superior gluteal nerve (SGN) arises from the sacral plexus and enters the gluteal region above the piriformis where it divides into superior and an inferior branches. Former ends in the gluteus medius and occasionally gluteus minimus whereas latter supplies gluteus medius and minimus and ends in tensor fascia latae. Variations, relations, branching pattern and length of the SGN were reported in earlier studies. The present study was conducted to establish preliminary data on the length and branching pattern of the SGN and its relations with the neighbouring bony landmarks. Twenty two lower extremities were examined in 22 male and 13 female formalin fixed cadavers. Tip of the greater trochanter was determined as the point of reference. Statistical analysis was done using student's T test. Present study will help orthopedicians performing total hip replacement through lateral and transgluteal approaches (Tab. 3, Fig. 4, Ref. 19).

Impact of acamprosate on behavior and brain-derived neurotrophic factor: an open-label study in youth with fragile X syndrome

RATIONALE

Fragile X syndrome (FXS) is an inherited form of developmental disability and a single gene cause of autism. As a disorder with increasingly understood pathophysiology, FXS is a model form of developmental disability for targeted drug development efforts. Preclinical animal model findings have focused targeted drug treatment development in FXS on an imbalance between excessive glutamate and deficient gamma-aminobutyric acid (GABA) neurotransmission.

METHODS

We conducted a prospective open-label 10-week trial of acamprosate in 12 youth aged 6-17 years (mean age: 11.9 years) with FXS.

RESULTS

Acamprosate use (mean dose: 1,054  ±  422 mg/day) was associated with treatment response (defined by a Clinical Global Impressions Improvement (CGI-I) scale score of "very much improved" or "much improved") in nine of 12 (75 %) subjects. Improvement was noted in social behavior and inattention/hyperactivity using multiple standard behavioral outcome measures. No significant adverse effects or changes in vital signs, including weight or laboratory measures, occurred during treatment with acamprosate. Additionally, pre- and post-treatment blood biomarker analyses looking at brain-derived neurotrophic factor (BDNF) levels found a significant increase in BDNF with treatment. In our pilot sample, treatment response did not correlate with change in BDNF with treatment.

CONCLUSIONS

Acamprosate was generally safe and well tolerated and was associated with a significant improvement in social behavior and a reduction in inattention/hyperactivity. The increase in BDNF that occurred with treatment may be a useful pharmacodynamic marker in future acamprosate studies. Given these findings, a double-blind, placebo-controlled study of acamprosate in youth with FXS is warranted.

Autism as early neurodevelopmental disorder: evidence for an sAPPα-mediated anabolic pathway

Autism is a neurodevelopmental disorder marked by social skills and communication deficits and interfering repetitive behavior. Intellectual disability often accompanies autism. In addition to behavioral deficits, autism is characterized by neuropathology and brain overgrowth. Increased intracranial volume often accompanies this brain growth. We have found that the Alzheimer's disease (AD) associated amyloid-β precursor protein (APP), especially its neuroprotective processing product, secreted APP α, is elevated in persons with autism. This has led to the "anabolic hypothesis" of autism etiology, in which neuronal overgrowth in the brain results in interneuronal misconnections that may underlie multiple autism symptoms. We review the contribution of research in brain volume and of APP to the anabolic hypothesis, and relate APP to other proteins and pathways that have already been directly associated with autism, such as fragile X mental retardation protein, Ras small GTPase/extracellular signal-regulated kinase, and phosphoinositide 3 kinase/protein kinase B/mammalian target of rapamycin. We also present additional evidence of magnetic resonance imaging intracranial measurements in favor of the anabolic hypothesis. Finally, since it appears that APP's involvement in autism is part of a multi-partner network, we extend this concept into the inherently interactive realm of epigenetics. We speculate that the underlying molecular abnormalities that influence APP's contribution to autism are epigenetic markers overlaid onto potentially vulnerable gene sequences due to environmental influence.

High-affinity choline uptake (HACU) and choline acetyltransferase (ChAT) activity in neuronal cultures for mechanistic and drug discovery studies

Acetylcholine (ACh) is the neurotransmitter used by cholinergic neurons at the neuromuscular junction, in parasympathetic peripheral nerve terminals, and in important memory-related circuits in the brain, and takes part in other critical functions. ACh is synthesized from choline and acetyl coenzyme A by the enzyme choline acetyltransferase (ChAT). The formation of ACh in cholinergic nerve terminals requires the transport of choline into cells from the extracellular space and the activity of ChAT. High-affinity choline uptake (HACU) represents the majority of choline uptake into the nerve terminal and is the acutely regulated, rate-limiting step in ACh synthesis. HACU can be differentiated from nonspecific choline uptake by inhibition of the choline transporter with hemicholinium. Several methods have been described previously to measure HACU and ChAT activity simultaneously in synaptosomes, but a well-documented protocol for cultured cells is lacking. We describe a procedure for simultaneous measurement of HACU and ChAT in cultured cells by simple radionuclide-based techniques. Using this procedure, we have quantitatively determined HACU and ChAT activity in cholinergically differentiated human neuroblastoma (SK-N-SH) cells. These simple methods can be used for neurochemical and drug discovery studies relevant to several disorders, including Alzheimer's disease, myasthenia gravis, and cardiovascular disease.

Effect of cyclophosphamide exposure on the migration of primordial germ cells in rat fetuses

OBJECTIVES OF THE STUDY

Effect of a single dose of cyclophosphamide on migration of the primordial germ cells (PGC), when they are about to reach gonadal ridge was investigated histochemically by staining for alkaline phosphatase. This may throw some light on the fate of gonadal ridge when exposed to the drug itself or its breakdown products such as acrolein, which is present as an environmental pollutant.

MATERIALS AND METHODS

Twelve pregnant Charles foster rats were divided in to control and treatment groups and kept in separate cages. In the experimental group, Cyclophosphamide 20 mg/kg/body weight was injected intraperitoneally on day 12 of gestation. Transverse sections of fetuses collected on day 16 of gestation were stained for alkaline phosphatase activity. Outcome of the study was analysed by scanning the photomicrographs and represented by photomicrographs.

RESULTS

An unique finding in experimental group in the gonadal ridge consisted of homogeneously distributed pale staining cells. The gonadal ridge-mesonephros junction showed a single big cluster of the PGC. Under higher magnification, the PGC could be identified by oval or circular shape with well-defined cell membranes and very distinct dark brown staining. There were no signs of degeneration or disintegration of these cells.

CONCLUSIONS

Cyclophosphamide exposure led to failure of PGC to spread inwards from the gonadal ridge-mesonephros junction giving rise to a situation so far not reported in literature. The presented phenomenon will result in improper development of the gonads leading to infertility in an affected individual in future generation (Fig. 4, Ref. 18).

Analysis of the arterial anatomical variations of thyroid gland: anatomic guide for surgical neck dissection

PURPOSE

Aim of this study was to establish preliminary data on the variations of arterial supply of thyroid gland in Karnataka population.

METHODS

The anterior triangles in the neck of formalin fixed cadavers were dissected. The length, branching pattern, number and length of branches of superior thyroid artery (STA) were noted. We measured the length of inferior thyroid artery (ITA) from its point of emergence from thyrocervical trunk (TCT) to lower pole of thyroid gland. The length of the external carotid artery (ECA), TCT from the point of its emergence to the point of its branching was noted. We noted the number of branches from ITA and TCT. Presence of any additional artery supplying the thyroid gland was searched for. Difference in the length of STA and ITA between the two sexes and sides were noted. Statistical analysis was done by Student's t-test.

RESULTS

In our study the maximum length of STA was 5.34cm and that of ITA was 5.07cm and there were no statistically significant side-to-side differences in level of bifurcation.

CONCLUSIONS

Observations of the present study on the course and branching pattern of arteries around thyroid gland will help in easier approach during thyroid surgeries and interventional techniques (Tab. 1, Fig. 3, Ref. 38).

Ovarian development in Wistar rat treated prenatally with single dose diisobutyl phthalate

Phthalates are a class of industrial compounds with an array of toxicological properties used in day to day life. Diisobutyl phthalate on (DIBP) is used as an additive to keep the plastics soft or flexible (plasticizer) in nitrocellulose plastic, nail polish, explosives, lacquer manufacturing etc. Although DIBP exposure in humans is generally low, people in adhesive industries and pharmaceutical industries are exposed to higher levels. The aim of this study was to determine the effect of single dose of DIBP on developing ovary of Wistar rat. One hundred and eight adult pregnant Wistar rats were divided into control and experimental groups. Rats in experimental group were given DIBP on day 10, 12 and 14 of gestation at 0.375, 0.75 and 1.25 ml/kg body weight dose intraperitoneally in a single dose. Sections of ovaries collected on day 21 of gestation were stained with hematoxylin and eosin and examined and Masson's trichrome histologically. Sections belonging to the control group showed the presence of oocytes in clusters separated by thin fibrous septa. Degeneration oocytes, empty follicles surrounded by follicular cells without gonocytes in the center were observed in ovarian stroma. Blood vessels in the ovarian stroma were prominent and congested. Around a bunch of follicles total architectural disarray was observed although on special staining fibrosis was not evident. As pregnant women are constantly exposed, effect of DIBP on ovary of a developing fetus would denote the long term consequence in future generations (Fig. 5, Ref. 39).