The Safety of Micro-Implants for the Brain

Technological advancements in electronics and micromachining now allow the development of discrete wireless brain implantable micro-devices. Applications of such devices include stimulation or sensing and could enable direct placement near regions of interest within the brain without the need for electrode leads or separate battery compartments that are at increased risk of breakage and infection. Clinical use of leadless brain implants is accompanied by novel risks, such as migration of the implant. Additionally, the encapsulation material of the implants plays an important role in mitigating unwanted tissue reactions. These risks have the potential to cause harm or reduce the service of life of the implant. In the present study, we have assessed post-implantation tissue reaction and migration of borosilicate glass-encapsulated micro-implants within the cortex of the brain. Twenty borosilicate glass-encapsulated devices (2 × 3.5 × 20 mm) were implanted into the parenchyma of 10 sheep for 6 months. Radiographs were taken directly post-surgery and at 3 and 6 months. Subsequently, sheep were euthanized, and GFAP and IBA-1 histological analysis was performed. The migration of the implants was tracked by reference to two stainless steel screws placed in the skull. We found no significant difference in fluoroscopy intensity of GFAP and a small difference in IBA-1 between implanted tissue and control. There was no glial scar formation found at the site of the implant’s track wall. Furthermore, we observed movement of up to 4.6 mm in a subset of implants in the first 3 months of implantation and no movement in any implant during the 3–6-month period of implantation. Subsequent histological analysis revealed no evidence of a migration track or tissue damage. We conclude that the implantation of this discrete micro-implant within the brain does not present additional risk due to migration.

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The risk of pulmonary tuberculosis after traumatic brain injury

Scientific Reports ◽

10.1038/s41598-021-87332-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hsin-Yueh Liu ◽

Kuang-Ming Liao ◽

Fu-Wen Liang ◽

Yi-Chieh Hung ◽

Jhi-Joung Wang ◽

...

Keyword(s):

Traumatic Brain Injury ◽

Brain Injury ◽

Pulmonary Infection ◽

Intracranial Injury ◽

Icu Patients ◽

Increased Risk ◽

Significant Difference ◽

Comparison Cohort ◽

Comorbidity Index ◽

The Brain

AbstractAfter traumatic brain injury (TBI), an inflammatory response in the brain might affect the immune system. The risk of pulmonary infection reportedly increases in patients with TBI. We aimed to evaluate the risk of tuberculosis (TB) in patients with TBI in Taiwan. All participants were selected from the intensive care unit (ICU). Patients with TBI were defined as patients in ICU with intracranial injury, and comparison cohort were patients in ICU without TBI diagnosis. There was a significant difference in TB risk between the patients with TBI and the comparison cohort according to age and the Charlson’s comorbidity index (CCI) score. Thus, we divided patients based on CCI into three groups for further analysis: mild (CCI = 0), moderate (CCI = 1/2), severe (CCI > 2). Mild-CCI group had a lower TB incidence rate (0.74%) and longer time to TB development (median: 2.43) than the other two groups. Moderate-CCI group had 1.52-fold increased risk of TB infection (p < 0.0001) compared with mild-CCI group. In the severe-CCI group, patients aged ≥ 80 years had 1.91-fold risk of TB compared with mild-CCI group (p = 0.0481). Severe-CCI group had significantly higher mortality than the mild-CCI group (p = 0.0366). Patients with TBI and more comorbidities had higher risk of TB infection with higher mortality rate.

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Histological analysis of the periapical tissues of dog deciduous teeth after root canal filling with diferent materials

Journal of Applied Oral Science ◽

10.1590/s1678-77572005000300021 ◽

2005 ◽

Vol 13 (3) ◽

pp. 318-324 ◽

Cited By ~ 3

Author(s):

Sueli Satomi Murata ◽

Roberto Holland ◽

Valdir de Souza ◽

Eloi Dezan Junior ◽

Juliana Aguiar de Grossi ◽

...

Keyword(s):

Root Canal ◽

Histological Analysis ◽

Tissue Reaction ◽

The Other ◽

Deciduous Teeth ◽

Control Group ◽

Root Canal Filling ◽

Root Canals ◽

Anterior Teeth ◽

Significant Difference

The problem of finding an ideal material for filling root canals of deciduous teeth has not been solved yet. This fact led to the development of an experiment to histologically analyze the periapical tissue reaction to 3 root canal filling materials. Eighty root canals of dog deciduous anterior teeth from 6 animals, 60 days old, were used in this study. After biomechanical preparation, the root canals were filled with the following materials: slowly resorbable Maisto paste, Sealer 26 with iodoform, L&C paste (calcium hydroxide with olive oil) and as a control group, canals that were prepared but not filled. At thirty days after the treatment the animals were killed and the teeth prepared for histological analysis. The materials were ranked statistically from the best to the worst as follows: a - Maisto paste, b - Sealer 26 with iodoform, c - control group, d - L&C paste. There was significant difference (p = 0.01) only when the results of the other groups were compared with the L&C paste group. It was also observed that L&C paste was not biologically compatible and that the other materials were biocompatible but their resorption was not at the same rate as that of the deciduous teeth roots.

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Tai Chi Training Evokes Significant Changes in Brain White Matter Network in Older Women

Healthcare ◽

10.3390/healthcare8010057 ◽

2020 ◽

Vol 8 (1) ◽

pp. 57 ◽

Cited By ~ 8

Author(s):

Chunlin Yue ◽

Liye Zou ◽

Jian Mei ◽

Damien Moore ◽

Fabian Herold ◽

...

Keyword(s):

White Matter ◽

Cognitive Decline ◽

Tai Chi ◽

Elderly Women ◽

Diffusion Tensor ◽

Brain White Matter ◽

Increased Risk ◽

Significant Difference ◽

The Brain ◽

Walking Group

Background: Cognitive decline is age relevant and it can start as early as middle age. The decline becomes more obvious among older adults, which is highly associated with increased risk of developing dementia (e.g., Alzheimer’s disease). White matter damage was found to be related to cognitive decline through aging. The purpose of the current study was to compare the effects of Tai Chi (TC) versus walking on the brain white matter network among Chinese elderly women. Methods: A cross-sectional study was conducted where 42 healthy elderly women were included. Tai Chi practitioners (20 females, average age: 62.9 ± 2.38 years, education level 9.05 ± 1.8 years) and the matched walking participants (22 females, average age: 63.27 ± 3.58 years, educational level: 8.86 ± 2.74 years) underwent resting-state functional magnetic resonance imaging (rsfMRI) scans. Diffusion tensor imaging (DTI) and graph theory were employed to study the data, construct the white matter matrix, and compare the brain network attributes between the two groups. Results: Results from graph-based analyses showed that the small-world attributes were higher for the TC group than for the walking group (p < 0.05, Cohen’s d = 1.534). Some effects were significant (p < 0.001) with very large effect sizes. Meanwhile, the aggregation coefficient and local efficiency attributes were also higher for the TC group than for the walking group (p > 0.05). However, no significant difference was found between the two groups in node attributes and edge analysis. Conclusion: Regular TC training is more conducive to optimize the brain functioning and networking of the elderly. The results of the current study help to identify the mechanisms underlying the cognitive protective effects of TC.

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Soft Tissue Anchoring Performance, Biomechanical Properties, and Tissue Reaction of a New Hernia Mesh Engineered to Address Hernia Occurrence and Recurrence

Journal of Medical Devices ◽

10.1115/1.4043740 ◽

2019 ◽

Vol 13 (4) ◽

Author(s):

Mohamad M. Ibrahim ◽

Jason L. Green ◽

Jeffrey Everitt ◽

David Ruppert ◽

Richard Glisson ◽

...

Keyword(s):

Physical Properties ◽

Histological Analysis ◽

Performance Testing ◽

Perioperative Period ◽

Areal Density ◽

Tissue Reaction ◽

Recurrence Rates ◽

Mesh Migration ◽

Hernia Mesh ◽

Significant Difference

Abstract One opportunity to reduce hernia occurrence and recurrence rates (currently estimated to be 30% at 10 years postoperatively) is by enhancing the ability of hernia meshes to anchor into tissue to prevent mesh migration, mesh contraction, and mesh tearing away from tissue. To address this, we developed a novel moderate-weight, macroporous, polypropylene mesh (termed the T-line mesh) with mesh extensions to optimize anchoring. We examined the physical properties, biomechanical performance, and biocompatibility of this novel mesh versus a predicate mesh anchored with #0-suture. The physical properties of the T-line mesh and predicate mesh were measured using American Society for Testing and Materials (ASTM) standards. Meshes were implanted into a swine hernia model and harvested after one day to determine anchoring strength of the meshes in the perioperative period. A separate group was implanted into a swine hernia model and harvested at 30 days and 90 days for semiquantitative histological analysis of biocompatibility. T-line mesh physical properties were similar to commonly used moderate-weight meshes in thickness and areal density. The T-line mesh outperformed the predicate mesh in all mechanical testing (P < 0.05). In the perioperative period, the T-line mesh was ∼275% stronger (P < 0.001) than the standard of care. Histological analysis of biocompatibility demonstrated no significant difference between the T-line mesh and predicate mesh (P > 0.05). The T-line mesh is a novel hernia mesh that outperforms a predicate mesh in mechanical and biomechanical performance testing while exhibiting similar biocompatibility. The T-line mesh has the potential to reduce hernia occurrence and recurrence caused by mechanical failure.

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Risk of venous thromboembolism following surgical treatment of superficial venous incompetence

VASA ◽

10.1024/0301-1526/a000656 ◽

2017 ◽

Vol 46 (6) ◽

pp. 484-489 ◽

Cited By ~ 7

Author(s):

Tom Barker ◽

Felicity Evison ◽

Ruth Benson ◽

Alok Tiwari

Keyword(s):

Venous Thromboembolism ◽

Varicose Vein ◽

Lower Incidence ◽

Varicose Veins ◽

Secondary Data ◽

Foam Sclerotherapy ◽

Increased Risk ◽

Significant Difference ◽

Chi Squared ◽

One Year

Abstract. Background: The invasive management of varicose veins has a known risk of post-operative deep venous thrombosis and subsequent pulmonary embolism. The aim of this study was to evaluate absolute and relative risk of venous thromboembolism (VTE) following commonly used varicose vein procedures. Patients and methods: A retrospective analysis of secondary data using Hospital Episode Statistics database was performed for all varicose vein procedures performed between 2003 and 2013 and all readmissions for VTE in the same patients within 30 days, 90 days, and one year. Comparison of the incidence of VTEs between procedures was performed using a Pearson’s Chi-squared test. Results: In total, 261,169 varicose vein procedures were performed during the period studied. There were 686 VTEs recorded at 30 days (0.26 % incidence), 884 at 90 days (0.34 % incidence), and 1,246 at one year (0.48 % incidence). The VTE incidence for different procedures was between 0.15–0.35 % at 30 days, 0.26–0.50 % at 90 days, and 0.46–0.58 % at one year. At 30 days there was a significantly lower incidence of VTEs for foam sclerotherapy compared to other procedures (p = 0.01). There was no difference in VTE incidence between procedures at 90 days (p = 0.13) or one year (p = 0.16). Conclusions: Patients undergoing varicose vein procedures have a small but appreciable increased risk of VTE compared to the general population, with the effect persisting at one year. Foam sclerotherapy had a lower incidence of VTE compared to other procedures at 30 days, but this effect did not persist at 90 days or at one year. There was no other significant difference in the incidence of VTE between open, endovenous, and foam sclerotherapy treatments.

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Interpersonal Violence and Substance Use Among Female Sexual Minorities

10.31234/osf.io/yws4d ◽

2019 ◽

Author(s):

Cort M. Dorn-Medeiros ◽

Cass Dykeman ◽

Timothy Bergquist

Keyword(s):

New York ◽

Tobacco Use ◽

Interpersonal Violence ◽

Sexual Minorities ◽

Sample Population ◽

Life Outcomes ◽

City Community ◽

Increased Risk ◽

Significant Difference ◽

Community Health Survey

This archived data study used results from the New York City Community Health Survey to explore the relationship between interpersonal violence among female sexual minorities (FSM) and their levels of alcohol and tobacco use. A total of 92 FSM were included in the sample population. There was a significant difference in the mean number of alcoholic drinks consumed between FSM who reported past experience of interpersonal violence and those who did not. No difference was found in levels of tobacco use between FSM who reported interpersonal violence and those who did not. Results of the present study support current research indicating FSM may be at increased risk for elevated alcohol use and respective negative life outcomes related to the experience of interpersonal violence.

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Association between hTERT Polymorphisms and Female Papillary Thyroid Carcinoma

Recent Patents on Anti-Cancer Drug Discovery ◽

10.2174/1574892814666190919145453 ◽

2019 ◽

Vol 14 (3) ◽

pp. 268-279

Author(s):

Ying Liu ◽

Zhi Li ◽

Xinyue Tang ◽

Min Li ◽

Feng Shi

Keyword(s):

Papillary Thyroid Carcinoma ◽

Thyroid Carcinoma ◽

Genome Wide Association Study ◽

Papillary Thyroid ◽

Clinicopathologic Characteristics ◽

Female Population ◽

Genome Wide ◽

Increased Risk ◽

Significant Difference ◽

Thyroid Cancer Risk

Background: A previous genome-wide association study showed that hTERT rs10069690 and rs2736100 polymorphisms were associated with thyroid cancer risk. Objective: This study further investigated the association between increased risk and clinicopathologic characteristics for Papillary Thyroid Carcinoma (PTC) and hTERT polymorphisms rs10069690 or rs2736100 in a Chinese female population. Methods: The hTERT genotypes of 276 PTC patients and 345 healthy subjects were determined with regard to SNPs rs10069690 and rs2736100. The association between these SNPs and the risk of PTC and clinicopathologic characteristics was investigated by logistic regression. Results: We found a significant difference between PTC and rs10069690 (Odds Ratio (OR) = 1.515; P = 0.005), but not between PTC and rs2736100. When the analysis was limited to females, rs10069690 and rs2736100 were both associated with increased risk for PTC in female individuals (OR = 1.647, P = 0.007; OR = 1.339, P = 0.041, respectively). Further haplotype analysis revealed a stimulative effect of haplotypes TC and CA of TERT rs10069690-rs2736100, which increased risk for PTC in female individuals (OR = 1.579, P = 0.014; OR = 0.726, P = 0.025, respectively). Furthermore, the heterozygote A/C of rs2736100 showed significant difference for age (OR = 0.514, P = 0.047). Conclusion: Our finding suggests that hTERT polymorphisms rs10069690 and rs2736100 are associated with increased risk for PTC in Chinese female population and rs2736100 may be related to age. Consistent with US20170360914 and US20170232075, they are expected to be a potential molecular target for anti-cancer therapy.

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Polymorphisms in alcohol metabolizing genes ADH2 and ADH3 and susceptibility to pancreatitis in alcoholics

International Journal of Bioassays ◽

10.21746/ijbio.2017.03.002 ◽

2017 ◽

Vol 6 (03) ◽

pp. 5297

Author(s):

Vedangi Aaren* ◽

Godi Sudhakar ◽

Girinadh L.R.S.

Keyword(s):

Frequency Distribution ◽

Ethanol Metabolism ◽

Alcoholic Pancreatitis ◽

Cytochrome P450 Enzyme ◽

Increased Risk ◽

Significant Difference ◽

Pcr Rflp ◽

P450 Enzyme ◽

Acute Alcoholic Pancreatitis ◽

Acute And Chronic Pancreatitis

In both developed and developing countries, overuse of alcohol is a considered as the major cause of acute and chronic pancreatitis. Prolonged overconsumption of alcohol for 5–10 years typically precedes the initial attack of acute alcoholic pancreatitis. It is observed that only a minority (around 5%) of alcoholics develop pancreatitis. It is now established that the pancreas has the capacity to metabolize ethanol. Previous studies have shown that there are two major pathways of ethanol metabolism, oxidative and non-oxidative. Oxidative ethanol metabolism involves the conversion of ethanol to acetaldehyde, a reaction that is catalysed by aldehyde dehydrogenase (ADH) with contributions from cytochrome P450 enzyme (CYP2E1) and possibly also catalase. Genetic factors regulating alcohol metabolism could predispose in developing alcoholic pancreatitis (AP). We investigated the association of polymorphisms in ADH enzymes with the alcoholic pancreatitis in North coastal Andhra Pradesh. Patients with alcoholic pancreatitis (AP; n = 100), alcoholic controls (AC; n = 100), and healthy controls (HC; n = 100) were included in the study. Blood samples were collected from the subjects in EDTA coated vials. DNA was extracted and genotyping for ADH2 and ADH3 was done by PCR-RFLP (polymerase chain reaction restriction fragment length polymorphism). The products were analysed by gel electrophoresis. The frequency distribution of ADH3*1/*1 genotype was significantly higher in AP group (54%) compared with AC (35%), and HC (42%), and was found to be associated with increased risk of alcoholic pancreatitis. There was no statistically significant difference between the frequency distribution of ADH3*1/*1, ADH3*1/*2, and ADH3*2/*2 genotypes between AC and HC. There was no statistically significant difference between the frequency distribution of ADH2*1/*1, ADH2*1/*2, and ADH2*2/*2 genotypes in AP compared with AC and HC. This study shows that carriers of ADH3*1/*1 individuals consuming alcohol are at higher risk for alcoholic pancreatitis than those with other genotypes such as ADH3*1/*2 and ADH3*2/*2.

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Seroprevalence of anti-SARS-CoV-2 IgG antibodies in hospitalized patients at a tertiary referral center in North India (Preprint)

10.2196/preprints.23937 ◽

2020 ◽

Author(s):

Dr. Animesh Ray ◽

Dr. Komal Singh ◽

Souvick Chattopadhyay ◽

Farha Mehdi ◽

Dr. Gaurav Batra ◽

...

Keyword(s):

Tertiary Care ◽

Age Groups ◽

Hospitalized Patients ◽

North India ◽

P Value ◽

Care Hospital ◽

Igg Antibodies ◽

Igg Antibody ◽

Increased Risk ◽

Significant Difference

BACKGROUND Seroprevalence of IgG antibodies against SARS-CoV-2 is an important tool to estimate the true extent of infection in a population. However, seroprevalence studies have been scarce in South East Asia including India, which, as of now, carries the third largest burden of confirmed cases in the world. The present study aimed to estimate the seroprevalence of anti-SARS-CoV-2 IgG antibody among hospitalized patients at one of the largest government hospital in India OBJECTIVE The primary objective of this study is to estimate the seroprevalence of SARS-CoV-2 antibody among patients admitted to the Medicine ward and ICU METHODS This cross-sectional study, conducted at a tertiary care hospital in North India, recruited consecutive patients who were negative for SARS-CoV-2 by RT-PCR or CB-NAAT. Anti-SARS-CoV-2 IgG antibody levels targeting recombinant spike receptor-binding domain (RBD) protein of SARS CoV-2 were estimated in serum sample by the ELISA method RESULTS A total of 212 hospitalized patients were recruited in the study with mean age (±SD) of 41.2 (±15.4) years and 55% male population. Positive serology against SARS CoV-2 was detected in 19.8%patients(95% CI 14.7-25.8). Residency in Delhi conferred a higher frequency of seropositivity 26.5% (95% CI 19.3-34.7) as compared to that of other states 8% (95% CI 3.0-16.4) with p-value 0.001. No particular age groups or socio-economic strata showed a higher proportion of seropositivity CONCLUSIONS Around, one-fifth of hospitalized patients, who were not diagnosed with COVID-19 before, demonstrated seropositivity against SARS-CoV-2. While there was no significant difference in the different age groups and socio-economic classes; residence in Delhi was associated with increased risk (relative risk of 3.62, 95% CI 1.59-8.21)

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PATH-19. MOLECULAR, HISTOLOGIC AND CLINICAL CHARACTERISTICS OF OLIGODENDROGLIOMAS: A MULTI-INSTITUTIONAL RETROSPECTIVE STUDY

Neuro-Oncology ◽

10.1093/neuonc/noaa215.701 ◽

2020 ◽

Vol 22 (Supplement_2) ◽

pp. ii168-ii168

Author(s):

Antonio Dono ◽

Kristin Alfaro-Munoz ◽

Yuanqing Yan ◽

Carlos Lopez-Garcia ◽

Zaid Soomro ◽

...

Keyword(s):

Health Science ◽

Cancer Center ◽

Subtotal Resection ◽

Adjuvant Radiation ◽

Science Center ◽

Who Grade ◽

Pik3ca Mutations ◽

Increased Risk ◽

Significant Difference ◽

Grade 3

Abstract In the 2016 WHO classification of CNS tumors, oligodendrogliomas are molecularly defined by IDH1 or IDH2 mutations and 1p/19q co-deletion. Some reports suggest that PI3K pathway alterations may confer increased risk of progression and poor prognosis in oligodendroglioma. However, factors that influence prognosis in molecularly defined oligodendroglioma (mOGD) have not been thoroughly studied. Also, the benefits of adjuvant radiation and temozolomide in mOGDs remain to be determined. 107 mOGDs diagnosed between 2008-2018 at the University of Texas Health Science Center at Houston (n= 39) and MD Anderson Cancer Center (n= 68) were included. A retrospective review of the demographic, clinical, histologic, molecular, and outcomes were performed. Median age at diagnosis was 37 years and 61 (57%) patients were male. There were 64 (60%) WHO Grade 2 and 43 (40%) WHO Grade 3 tumors. Ninety-five (88.8%) tumors were IDH1-mutant and 12 (11.2%) were IDH2-mutant. Eighty-two (77%) patients were stratified as high-risk: older than 40-years and/or subtotal resection (RTOG 9802). Gross-total resection was achieved in 47 (45%) patients. Treatment strategies included observation (n= 15), temozolomide (n= 11), radiation (n= 13), radiation with temozolomide (n= 62) and other (n= 6). Our results show a benefit of temozolomide vs. observation in progression-free survival (PFS). However, no benefit in PFS or overall survival (OS) was observed when comparing radiation vs. radiation with temozolomide. PIK3CA mutations were detected in 15 (14%) cases, and patients with PIK3CA-mutant mOGDs showed worse OS (10.7-years vs 15.1-years, p= 0.009). Patients with WHO Grade 3 tumors had shorter PFS but no significant difference in OS was observed compared to grade 2. Our findings suggest that mOGDs harboring PIK3CA mutations have worse OS. Except for an advantage in PFS in temozolomide treated patients, adjuvant treatment with radiation or the combination of both, showed no significant advantage in terms of OS.

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