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1.
Indian Pediatr ; 61(1): 62-65, 2024 01 15.
Article in English | MEDLINE | ID: mdl-38183255

ABSTRACT

OBJECTIVES: We studied the clinical characteristics and outcomes of neonates with congenital diaphragmatic hernia (CDH) admitted to a non-extracorporeal membrane oxygenation (ECMO) center. METHODS: A retrospective chart review of neonates with CDH admitted to a University Hospital, in Amman, Jordan, between 2005 and 2019. Demographic characteristics and their management details were extracted and factors associated with survival were analyzed. RESULTS: A total of 28 neonates born with CDH were included; their survival rate was 39.3%. Onset of respiratory distress, pre-operative ventilation, and length of hospitalization were significantly associated with mortality. Survival after surgery was significantly associated with a higher gestational age and a longer hospital stay. CONCLUSION: Our study showed a high mortality rate for CDH patients. Decreasing the health inequity and improved clinical interventions could improve outcomes.


Subject(s)
Hernias, Diaphragmatic, Congenital , Infant, Newborn , Humans , Hernias, Diaphragmatic, Congenital/therapy , Jordan/epidemiology , Retrospective Studies , Gestational Age , Hospitalization
2.
Med Phys ; 50(6): 3418-3434, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36841948

ABSTRACT

BACKGROUND: In breast CT, scattered photons form a large portion of the acquired signal, adversely impacting image quality throughout the frequency response of the imaging system. Prior studies provided evidence for a new image acquisition design, dubbed Narrow Beam Breast CT (NB-bCT), in preventing scatter acquisition. PURPOSE: Here, we report the design, implementation, and initial characterization of the first NB-bCT prototype. METHODS: The imaging system's apparatus is composed of two primary assemblies: a dynamic Fluence Modulator (collimator) and a photon-counting line detector. The design of the assemblies enables them to operate in lockstep during image acquisition, converting sourced x-rays into a moving narrow beam. During a projection, this narrow beam sweeps the entire fan angle coverage of the imaging system. The assemblies are each comprised of a metal housing, a sensory system, and a robotic system. A controller unit handles their relative movements. To study the impact of fluence modulation on the signal received in the detector, three physical breast phantoms, representative of small, average, and large size breasts, were developed and imaged, and acquired projections analyzed. The scatter acquisition in each projection as a function of breast phantom size was investigated. The imaging system's spatial resolution at the center and periphery of the field of view was measured. RESULTS: Minimal acquisition of scattered rays occurs during image acquisition with NB-bCT; results in minimal scatter to primary ratios in small, average, and large breast phantoms imaged were 0.05, 0.07, and 0.9, respectively. System spatial resolution of 5.2 lp/mm at 10% max MTF and 2.9 lp/mm at 50% max MTF at the center of the field of view was achieved, with minimal loss with the shift toward the corner (5.0 lp/mm at 10% max MTF and 2.5 lp/mm at 50% max MTF). CONCLUSION: The disclosed development, implementation, and characterization of a physical NB-bCT prototype system demonstrates a new method of CT-based image acquisition that yields high spatial resolution while minimizing scatter-components in acquired projections. This methodology holds promise for high-resolution CT-imaging applications in which reduction of scatter contamination is desirable.


Subject(s)
Tomography, X-Ray Computed , Tomography, X-Ray Computed/methods , Phantoms, Imaging , Scattering, Radiation
3.
BMC Womens Health ; 22(1): 204, 2022 06 02.
Article in English | MEDLINE | ID: mdl-35655199

ABSTRACT

INTRODUCTION: In the Muslim world, the use and acceptance of long-term and permanent contraceptives were limited. Our aim was to investigate those limiting factors so we can help making these methods widely available and acceptable to the society. METHODS AND DATA ANALYSIS: There were 1365 women from Facebook groups in the period 08/10/2020-8/11/2020. Participants were married women, living in Jordan. This was a cross-sectional study. Statistical Package for Social Sciences (SPSS), version 16, software was used for statistical analysis (Chicago, Illinois, USA). RESULTS: Among participants, 22.3% had never used any contraceptives. Non-hormonal IUCD was the most commonly used method. There was a statistically significant association between the use of hormonal IUCD and women's age, marriage duration, education and number of children (p < 0.0001). Tubal ligation was adopted by only 44 (3.22%) participants. 19.68% of participants declined tubal ligation merely due to religious issues. Women who completed only high school level of education underwent tubal ligation significantly more than those with university (Bachelor) and post-university (Master or PhD) degrees (p < 0.0001 and 0.026, respectively). Only 1.83% of women's partners underwent vasectomy, the majority of these vasectomies (72.0%) were done because of the need for lifelong contraception. Around 17% of women's partners had poor knowledge about vasectomy. Further, women's employment status (housewives or full-time employees) was found to be the only variable that affected acceptance of vasectomy (p = 0.0047). CONCLUSIONS: Women endured a heavy burden of contraception. Cultural and religious taboos influenced tubal ligation. Vasectomy was still very rarely adopted by men due to the lack of knowledge about the procedure. Our results raised the need for further dissemination of contraception knowledge and counselling through the primary care and maternity centers, mosques and media in official, comprehensive and integrated programs. Future research is needed in the field of permanent contraceptive methods.


Subject(s)
Social Media , Vasectomy , Child , Contraception/methods , Contraceptive Agents , Cross-Sectional Studies , Female , Humans , Male , Pregnancy
5.
Med Phys ; 49(1): 169-185, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34825715

ABSTRACT

PURPOSE: In cone-beam breast CT, scattered photons form a large portion of the acquired signal, adversely impacting image quality throughout the frequency response of the imaging system. Prior simulation studies provided proof of concept for utilization of a hardware solution to prevent scatter acquisition. Here, we report the design, implementation, and characterization of an auxiliary apparatus of fluence modulation and scatter shielding that does indeed lead to projections with a reduced level of scatter. METHODS: An apparatus was designed for permanent installation within an existing cone-beam CT system. The apparatus is composed of two primary assemblies: a "Fluence Modulator" (FM) and a "Scatter Shield" (SS). The design of the assemblies enables them to operate in synchrony during image acquisition, converting the sourced x-rays into a moving narrow beam. During a projection, this narrow beam sweeps the entire fan angle coverage of the imaging system. As the two assemblies are contingent on one another, their joint implementation is described in the singular as apparatus FM-SS. The FM and the SS assemblies are each comprised a metal housing, a sensory system, and a robotic system. A controller unit handles their relative movements. A series of comparative studies were conducted to evaluate the performance of a cone-beam CT system in two "modes" of operation: with and without FM-SS installed, and to compare the results of physical implementation with those previously simulated. The dynamic range requirements of the utilized detector in the cone-beam CT imaging system were first characterized, independent of the mode of operation. We then characterized and compared the spatial resolution of the imaging system with, and without, FM-SS. A physical breast phantom, representative of an average size breast, was developed and imaged. Actual differences in signal level obtained with, versus without, FM-SS were then compared to the expected level gains based on previously reported simulations. Following these initial assessments, the scatter acquisition in each projection in both modes of operation was investigated. Finally, as an initial study of the impact of FM-SS on radiation dose in an average size breast, a series of Monte Carlo simulations were coupled with physical measurements of air kerma, with and without FM-SS. RESULTS: With implementation of FM-SS, the detector's required dynamic range was reduced by a factor of 5.5. Substantial reduction in the acquisition of the scattered rays, by a factor of 5.1 was achieved. With the implementation of FM-SS, deposited dose was reduced by 27% in the studied breast. CONCLUSIONS: The disclosed implementation of FM-SS, within a cone-beam breast CT system, results in reduction of scatter-components in acquired projections, reduction of dose deposit to the breast, and relaxation of requirements for the detector's dynamic range. Controlling or correcting for patient motion occurring during image acquisition remains an open problem to be solved prior to practical clinical usage of FM-SS cone-beam breast CT.


Subject(s)
Breast , Cone-Beam Computed Tomography , Algorithms , Breast/diagnostic imaging , Humans , Monte Carlo Method , Phantoms, Imaging , Scattering, Radiation
6.
Front Hum Neurosci ; 15: 626406, 2021.
Article in English | MEDLINE | ID: mdl-33967720

ABSTRACT

Peak alpha frequency is known to vary not just between individuals, but also within an individual over time. While variance in this metric between individuals has been tied to working memory performance, less understood are how short timescale modulations of peak alpha frequency during task performance may facilitate behavior. This gap in understanding may be bridged by consideration of a key difference between individuals: sex. Inconsistent findings in the literature regarding the relationship between peak alpha frequency and cognitive performance, as well as known sex-related-differences in peak alpha frequency and its modulation motivated our hypothesis that cognitive and neural processes underlying working memory-modulation of peak alpha frequency in particular-may differ based upon sex. Targeting sex as a predictive factor, we analyzed the EEG data of participants recorded while they performed four versions of a visual spatial working memory task. A significant difference between groups was present: females modulated peak alpha frequency more than males. Task performance did not differ by sex, yet a relationship between accuracy and peak alpha frequency was present in males, but not in females. These findings highlight the importance of considering sex as a factor in the study of oscillatory activity, particularly to further understanding of the neural mechanisms that underlie working memory.

7.
J Clin Invest ; 125(3): 1163-73, 2015 Mar 02.
Article in English | MEDLINE | ID: mdl-25642774

ABSTRACT

UNLABELLED: Role of the funding source: Funding from the NIH was used for support of the participating clinical centers and the coordinating center. The funding source did not participate in the collection or the analysis of the data. BACKGROUND: The ß cell killing that characterizes type 1 diabetes (T1D) is thought to begin years before patients present clinically with metabolic decompensation; however, this primary pathologic process of the disease has not been measured. METHODS: Here, we measured ß cell death with an assay that detects ß cell-derived unmethylated insulin (INS) DNA. Using this assay, we performed an observational study of 50 participants from 2 cohorts at risk for developing T1D from the TrialNet Pathway to Prevention study and of 4 subjects who received islet autotransplants. RESULTS: In at-risk subjects, those who progressed to T1D had average levels of unmethylated INS DNA that were elevated modestly compared with those of healthy control subjects. In at-risk individuals that progressed to T1D, the observed increases in unmethylated INS DNA were associated with decreases in insulin secretion, indicating that the changes in unmethylated INS DNA are indicative of ß cell killing. Subjects at high risk for T1D had levels of unmethylated INS DNA that were higher than those of healthy controls and higher than the levels of unmethylated INS DNA in the at-risk progressor and at-risk nonprogressor groups followed for 4 years. Evaluation of insulin secretory kinetics also distinguished high-risk subjects who progressed to overt disease from those who did not. CONCLUSION: We conclude that a blood test that measures unmethylated INS DNA serves as a marker of active ß cell killing as the result of T1D-associated autoimmunity. Together, the data support the concept that ß cell killing occurs sporadically during the years prior to diagnosis of T1D and is more intense in the peridiagnosis period. TRIAL REGISTRATION: Clinicaltrials.gov NCT00097292. FUNDING: Funding was from the NIH, the Juvenile Diabetes Research Foundation, and the American Diabetes Association.


Subject(s)
Diabetes Mellitus, Type 1/pathology , Insulin-Secreting Cells/physiology , Cell Death , Child , DNA Methylation , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/metabolism , Diabetes Mellitus, Type 1/prevention & control , Disease Progression , Glucose Intolerance , Humans , Insulin/genetics , Prospective Studies , Risk
8.
Diabetes Care ; 37(1): 210-6, 2014.
Article in English | MEDLINE | ID: mdl-23939544

ABSTRACT

OBJECTIVE Glucagon-like peptide 1 (GLP-1) is an incretin hormone that is released from the gastrointestinal tract. Treatment with GLP-1 analogs has proven to be of clinical use for patients with type 2 diabetes. Patients with type 1 diabetes, particularly those with residual ß-cell function, may also respond to treatment, but the acute metabolic effects of GLP-1 analogs on these patients in reaction to both oral and intravenous glucose challenges are not well understood. RESEARCH DESIGN AND METHODS Seventeen patients with type 1 diabetes, half of whom had residual insulin production, underwent two mixed-meal tolerance tests (MMTTs) and two intravenous glucose tolerance tests (IVGTTs), with and without pretreatment with exenatide. No exogenous bolus insulin was administered for the studies. Glucose excursions, insulin secretion rates (ISRs), and levels of glucagon, endogenous GLP-1, and gastric inhibitory polypeptide were measured after the meal or glucose loads. RESULTS During the MMTT, glucose levels were suppressed with exenatide in patients with or without residual insulin production (P = 0.0003). Exenatide treatment did not change the absolute ISR, but the ISR to glucose levels were increased (P = 0.0078). Gastric emptying was delayed (P = 0.0017), and glucagon was suppressed (P = 0.0015). None of these hormonal or glucose changes were detected during the IVGTT with exenatide administration. CONCLUSIONS Exenatide showed a significant antidiabetogenic effect prior to an oral meal in patients with type 1 diabetes involving glucagon suppression and gastric emptying, while preserving increased insulin secretion. GLP-1 analogs may be useful as an adjunctive treatment in type 1 diabetes.


Subject(s)
Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 1/metabolism , Glucose/pharmacology , Hypoglycemic Agents/therapeutic use , Insulin-Secreting Cells/metabolism , Peptides/therapeutic use , Venoms/therapeutic use , Administration, Intravenous , Administration, Oral , Adolescent , Adult , Exenatide , Female , Gastric Emptying/drug effects , Gastric Inhibitory Polypeptide/blood , Glucagon/blood , Glucagon-Like Peptide 1/blood , Glucose/administration & dosage , Glucose Tolerance Test/methods , Humans , Insulin/metabolism , Male , Middle Aged , Young Adult
9.
Diabetes Metab Res Rev ; 30(2): 154-62, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24115337

ABSTRACT

BACKGROUND: Some patients with long-standing type 1 diabetes (T1D) maintain detectable levels of C-peptide. The quantitative and qualitative aspects of insulin secretion in these subjects have not been assessed, but may shed light on the basis for maintained ß cell function. Our objective was to characterize insulin secretion in subjects with varying duration of T1D. METHODS: Data from mixed-meal tolerance tests were collected in this cross-sectional study. We screened 58 subjects with T1D <1 year and 34 subjects with T1D >2 years, 20 of whom had previously participated in trials of anti-CD3 monoclonal antibody. Data from 38 historical non-diabetic controls were utilized. Insulin secretory rates were calculated from C-peptide levels from mixed-meal tolerance tests. Patterns and rates of insulin secretion were characterized along with relationships between insulin secretion and clinical parameters. RESULTS: C-peptide was detected in 68% of subjects with T1D duration >2 years. Insulin secretion was negatively correlated with HgbA(1c) and insulin use. A decline in total insulin secretion was seen with increasing disease duration (p < 0.0001). More subjects with long duration of T1D had a delayed time to peak secretion compared with those with new onset T1D or non-diabetic subjects. Insulin and glucagon secretory responses appeared unrelated. CONCLUSIONS: Meal-stimulated insulin secretory responses are seen in those with long-standing T1D and detectable C-peptide. Delayed insulin secretory responses are more common in individuals with longer disease duration. Residual insulin secretory responses are associated with improved clinical parameters.


Subject(s)
Diabetes Mellitus, Type 1/physiopathology , Disease Progression , Down-Regulation , Insulin-Secreting Cells/metabolism , Insulin/metabolism , Adolescent , Adult , C-Peptide/blood , Child , Cohort Studies , Cross-Sectional Studies , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/drug therapy , Down-Regulation/drug effects , Female , Glucagon/metabolism , Glucagon-Secreting Cells/drug effects , Glucagon-Secreting Cells/metabolism , Glycated Hemoglobin/analysis , Humans , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Insulin Secretion , Insulin-Secreting Cells/drug effects , Male , Postprandial Period , Young Adult
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