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1.
Int J Oral Maxillofac Surg ; 53(4): 293-300, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37739816

ABSTRACT

Midface hypoplasia in syndromic craniosynostosis (SC) may lead to serious respiratory issues. The aim of this study was to analyse the morphometric correlation between midface and cranial base parameters in paediatric SC patients in order to formulate predictive regression models. The computed tomography scans of 18 SC patients and 20 control were imported into Materialise Mimics Medical version 21.0 software for the measurement of multiple craniofacial landmarks and correlation analysis. The results showed a strong correlation of anterior cranial base (SN), posterior cranial base (SBa), and total cranial base (NBa) (r = 0.935) to maxilla length and width (ZMR-ZML) (r = 0.864). The model of NBa = - 1.554 + 1.021(SN) + 0.753(SBa) with R2 = 0.875 is proposed to demonstrate the development of the cranial base that causes a certain degree of midface hypoplasia in SC patients. The formula is supported using a prediction model of ZMR-ZML = 5.762 + 0.920(NBa), with R2 = 0.746. The mean absolute difference and standard deviation between the predicted and true NBa and ZMR-ZML were 2.08 ± 1.50 mm and 3.11 ± 2.32 mm, respectively. The skeletal growth estimation models provide valuable foundation for further analysis and potential clinical application.


Subject(s)
Craniosynostoses , Humans , Child , Craniosynostoses/diagnostic imaging , Face , Skull Base , Software , Tomography, X-Ray Computed , Cephalometry
2.
Phys Rev Lett ; 122(25): 251101, 2019 Jun 28.
Article in English | MEDLINE | ID: mdl-31347906

ABSTRACT

Thus far, all known ghost-free interactions of multiple spin-2 fields have involved at most pairwise couplings of the fields, which are direct generalizations of bimetric interactions. We present a class of spin-2 theories with genuine multifield interactions and explicitly demonstrate the absence of ghost instabilities. The construction involves integrating out a nondynamical field in a theory of spin-2 fields with only pairwise ghost-free interactions. The new multivierbein interactions generated are not always expressible in terms of the associated metrics.

3.
Neuroscience ; 295: 209-20, 2015 Jun 04.
Article in English | MEDLINE | ID: mdl-25813709

ABSTRACT

Methamphetamine (METH) is a psychostimulant that disrupts monoaminergic neurotransmission to evoke profound behavioral and physiological effects. Rapidly distributing to forebrain regions to increase synaptic concentrations of three monoamines (dopamine (DA), serotonin (5-HT) and noradrenaline (NA)), the medial prefrontal cortex (mPFC) is important in METH-altered behavioral and psychological profiles. Activation of the ventral mPFC can modify physiological variables, however, METH-evoked autonomic changes from this region are unknown. Therefore, the aim of this study was to characterize the respiratory, metabolic and cardiovascular effects of microinjection of METH, DA, 5-HT and NA into the ventral mPFC in urethane-anesthetized Sprague-Dawley rats. METH and NA microinjection evoked dose-related increases in heart rate, interscapular brown adipose tissue temperature and expired CO2, a pattern of response characteristic of non-shivering thermogenesis. NA and 5-HT microinjection elicited pressor and depressor responses, respectively, with matching baroreflex adjustments in sympathetic nerve activity while METH and DA evoked no change in vasomotor outflow. Low doses of METH and DA may evoke respiratory depression. These data suggest that METH's actions in the ventral mPFC, likely via adrenergic receptors, evoke non-shivering thermogenesis which may contribute to the increased body temperature and tachycardia seen in those that abuse METH.


Subject(s)
Biogenic Monoamines/pharmacology , Central Nervous System Stimulants/pharmacology , Heart Rate/drug effects , Methamphetamine/pharmacology , Prefrontal Cortex/drug effects , Thermogenesis/drug effects , Analysis of Variance , Animals , Blood Pressure/drug effects , Dopamine/pharmacology , Dose-Response Relationship, Drug , Male , Norepinephrine/pharmacology , Prefrontal Cortex/physiology , Rats , Rats, Sprague-Dawley , Serotonin/pharmacology , Sympathetic Nervous System/drug effects , Sympathetic Nervous System/physiology
4.
Pediatr Surg Int ; 29(5): 437-43, 2013 May.
Article in English | MEDLINE | ID: mdl-23411614

ABSTRACT

PURPOSE: Our institution routinely utilizes needle core biopsy (NCB), instead of fine needle aspiration, in the evaluation of pediatric thyroid nodules. This practice initially arose from limited cytopathology services in our hospital. Given the lack of information regarding the utility of NCB in diagnosing pediatric thyroid neoplasms, we set out to review our institution's experience with this technique. METHODS: We performed a single institution retrospective chart review of all children who underwent thyroidectomy for primary thyroid pathology. RESULTS: Seventy-four patients, with a mean age of 12.9 ± 4.5 (SD) years, underwent partial or total thyroidectomy between 2002 and 2010. Seven of these patients had medically refractive hyperthyroidism. The remaining 67 patients had one or more thyroid nodules as identified by ultrasound. 24 (36 %) of these cases were malignant on final pathology. 14 (58 %) of the malignant cases were papillary thyroid carcinoma. 46 of the thyroid nodule cases underwent pre-operative NCB. Biopsy results for these patients were non-diagnostic in 6 (13 %), benign in 11 (24 %), atypical in 17 (37 %), and malignant in 12 (26 %). There were no complications arising from NCB. Sensitivity of NCB for diagnosing papillary carcinoma (PC) and follicular neoplasm was calculated at 0.88 (0.47-1.0, 95 % CI) and 0.84 (0.60-0.97, 95 % CI), respectively. Of the 28 patients not undergoing preoperative NCB, 12 underwent hemithyroidectomy, with one patient (8 %) requiring completion thyroidectomy for PC. Overall, the sensitivity of NCB in diagnosing PC and follicular thyroid neoplasms was 0.85 (0.55-0.99, 95 % CI), while the specificity was 0.63 (0.42-0.82, 95 % CI). CONCLUSIONS: Needle core biopsy appears to have a low rate of associated complications, and its sensitivity for diagnosing PC and follicular neoplasm is comparable to what has been reported for fine needle aspiration biopsy in a similar patient population.


Subject(s)
Thyroid Gland/pathology , Thyroid Neoplasms/pathology , Adolescent , Biopsy, Fine-Needle , Biopsy, Large-Core Needle , Child , Female , Humans , Male , Retrospective Studies , Sensitivity and Specificity , Thyroid Neoplasms/surgery , Thyroidectomy
5.
Phys Rev Lett ; 108(4): 041101, 2012 Jan 27.
Article in English | MEDLINE | ID: mdl-22400821

ABSTRACT

We analyze the ghost issue in the recently proposed models of nonlinear massive gravity in the Arnowitt-Deser-Misner formalism. We show that, in the entire two-parameter family of actions, the Hamiltonian constraint is maintained at the complete nonlinear level and we argue for the existence of a nontrivial secondary constraint. This implies the absence of the pathological Boulware-Deser ghost to all orders. To our knowledge, this is the first demonstration of the existence of a consistent theory of massive gravity at the complete nonlinear level, in four dimensions.

6.
Eur J Pediatr Surg ; 21(5): 287-91, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21780019

ABSTRACT

INTRODUCTION: Primary suture-less closure of gastroschisis using negative pressure dressing (wound vacuum) involves the application of an initial preformed Silo with subsequent bedside suture-less closure of the defect using negative pressure dressing. The advantages of this gentle approach are the simple bedside closure without intubation, paralysis or ventilation as well as reduced risk of barotrauma, abdominal compartment syndrome, acidosis, bowel infarction and necrotizing enterocolitis. This study is a report of the technique we used for gastroschisis closure at our institute. METHODS: The medical records of 15 newborns who underwent primary suture-less closure of gastroschisis using a negative pressure dressing (wound vacuum) technique between March 2008 and February 2010 were retrospectively reviewed. Outcome criteria such as time on ventilation, time to initiating feeds, time to full feeds, time to discharge from NICU and complications were recorded. RESULTS: The median follow-up was 234 days (range: 13-528 days). The time on ventilation was (n = 8: no ventilation; n = 3: 1 day; n = 2: 2-5 days; n = 2: > 5 days). The median time to initiating feeds was 13 days (range: 6-61 days), the median time to full feeds was 20 days (range: 12-91 days) and the median time to discharge was 24 days (range: 21-131 days). 2 patients had a tiny umbilical hernia at last follow-up. CONCLUSION: Primary suture-less closure of gastroschisis using a negative pressure dressing (wound vacuum) technique is easily reversible, does not need intubation/ventilation, avoids a trip to the operating room (OR), has minimal to no complications and provides good cosmetic results.


Subject(s)
Gastroschisis/surgery , Negative-Pressure Wound Therapy/methods , Female , Humans , Infant, Newborn , Male , Retrospective Studies
7.
Nanotechnology ; 22(29): 292001, 2011 Jul 22.
Article in English | MEDLINE | ID: mdl-21680966

ABSTRACT

Desalination of seawater and brackish water is becoming an increasingly important means to address the scarcity of fresh water resources in the world. Decreasing the energy requirements and infrastructure costs of existing desalination technologies remains a challenge. By enabling the manipulation of matter and control of transport at nanometer length scales, the emergence of nanotechnology offers new opportunities to advance water desalination technologies. This review focuses on nanostructured materials that are directly involved in the separation of water from salt as opposed to mitigating issues such as fouling. We discuss separation mechanisms and novel transport phenomena in materials including zeolites, carbon nanotubes, and graphene with potential applications to reverse osmosis, capacitive deionization, and multi-stage flash, among others. Such nanostructured materials can potentially enable the development of next-generation desalination systems with increased efficiency and capacity.


Subject(s)
Nanostructures/chemistry , Salinity , Salts/isolation & purification , Sodium Chloride/isolation & purification , Water Purification/methods , Nanostructures/ultrastructure , Osmosis , Phase Transition
8.
J Nanosci Nanotechnol ; 10(2): 956-64, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20352742

ABSTRACT

AZ31 nanocomposite containing carbon nanotube (CNT) reinforcement was fabricated using solidification processing followed by hot extrusion. The CNT reinforcement was integrated with AZ31 using an Al foil method. The AZ31 nanocomposite exhibited slightly smaller grain and intermetallic particle sizes than monolithic AZ31, reasonable CNT distribution, dominant (10 - 11) texture in the transverse and longitudinal directions unlike monolithic AZ31, and 48% higher hardness than monolithic AZ31. Compared to monolithic AZ31, the AZ31 nanocomposite exhibited higher 0.2%TYS, UTS, tensile failure strain and tensile work of fracture (WOF) (+10%, +17%, +68% and +92%, respectively). Similarly, compared to monolithic AZ31, the AZ31 nanocomposite exhibited higher 0.2%CYS, UCS, average compressive failure strain and compressive WOF (+58%, +3%, +5% and +17%, respectively). Inclusive of crystallographic texture changes, the effect of CNT integration on the enhancement of tensile and compressive properties of AZ31 is investigated in this paper.

9.
Drug Metabol Drug Interact ; 7(2-3): 111-41, 1989.
Article in English | MEDLINE | ID: mdl-2630176

ABSTRACT

Several new analogues of adenosine bearing a lipophilic side chain at the 5'-position have been synthesized and investigated for their ability to inhibit histamine N-methyltransferase (HNMT). The 5'-deoxy-5'-[4-(3-indolyl)but-1-yl]thio]adenosine (2e), exhibited a pI50 of 5.00 against guinea pig brain HNMT. Interestingly, the polar methyl sulphonium analogue (1c) was a more potent inhibitor of this enzyme (pI50 = 5.26). Both compounds were relatively ineffective inhibitors of rabbit adrenal phenylethanolamine N-methyltransferase (PNMT), rabbit lung indoleamine N-methyltransferase (INMT), and rat brain catechol O-methyltransferase (COMT). 5'-[N(4-phenylbutyl)]-amino-5'deoxyadenosine (2a) and 5'-[N-methyl,N-(4-phenylbutyl]-amino-5'deoxyadenosine (2b) also exhibited potent and selective inhibition against guinea pig brain HNMT. Results from kinetic studies indicate that the above compounds are inhibitors that compete for both the histamine and the S-adenosylmethionine (SAM) binding sites of HNMT. Compound 1c is one of the most potent adenosine analogue inhibitors of HNMT known.


Subject(s)
Adenosine/analogs & derivatives , Histamine N-Methyltransferase/antagonists & inhibitors , Methyltransferases/antagonists & inhibitors , Thionucleosides/pharmacology , Adenosine/chemical synthesis , Adenosine/pharmacology , Adrenal Glands/enzymology , Animals , Brain/drug effects , Brain/enzymology , Chemical Phenomena , Chemistry , Guinea Pigs , In Vitro Techniques , Kinetics , Phenylethanolamine N-Methyltransferase/antagonists & inhibitors , Rabbits , Rats , S-Adenosylmethionine/metabolism , Thionucleosides/chemical synthesis
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