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1.
Foot Ankle Orthop ; 9(2): 24730114241241320, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38617581

ABSTRACT

Background: Percutaneous Zadek osteotomy (ZO) has emerged as a surgical treatment of insertional Achilles tendinopathy (IAT) over the last decade. Existing literature is limited regarding the comparison of this approach with the more established, open ZO technique. This systematic review aims to evaluate and compare the current data on open vs percutaneous ZO approaches to help set evidence-based guidelines. Methods: A systematic literature search was performed using the keywords (Zadek osteotomy) OR (Keck and Kelly osteotomy) OR (dorsal closing wedge calcaneal osteotomy) OR (Haglund Deformity) OR (Haglund Syndrome) OR (Insertional Achilles Tendinopathy) and MeSH terms Osteotomy, Calcaneus, Syndrome, Insertional, Achilles tendon, and Tendinopathy. Our search included the following databases: PubMed, Embase, and the Cochrane Library. The PRISMA protocol and the Cochrane Handbook guidelines were followed. All studies included were published from 2009 to 2024 and included the use of open or percutaneous approaches of ZO for the treatment of IAT with at least a 12-month follow-up. The MINORS score criteria were used to evaluate the strength and quality of studies. Results: A total of 17 studies were reviewed, including 611 subjects and 625 ZO procedures. Of these procedures, 81 (11%) subjects had a percutaneous and 544 (89%) subjects had an open ZO. The mean follow-up time was 16.1 months for patients treated with percutaneous ZO and 36.1 months for patients treated with open ZO. Both open and percutaneous studies included in this review showed postoperative improvements in AOFAS, FFI, VISA-A, and VAS scores in patients with IAT. The reported complication rate was 5.8% among patients treated with percutaneous ZO and 10.2% among patients treated with open ZO. Conclusion: Percutaneous ZO is an emerging approach with substantially fewer documented cases compared with the open ZO. Both percutaneous and open ZO appear to be relatively effective treatments for insertional Achilles tendinopathy with Haglund's deformity. The lower complication rates reported for percutaneous ZO is encouraging. Further investigation with more subjects undergoing percutaneous ZO is clearly needed.

3.
Epidemiol Psychiatr Sci ; 33: e22, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38602075

ABSTRACT

AIMS: In the United States, lesbian, gay, bisexual, transgender, queer, intersex, asexual and other sexually minoritized and gender expansive (LGBTQ+) young adults are at increased risk for experiencing mental health inequities, including anxiety, depression and psychological distress-related challenges associated with their sexual and gender identities. LGBTQ+ young adults may have unique experiences of sexual and gender minority-related vulnerability because of LGBTQ+-related minority stress and stressors, such as heterosexism, family rejection, identity concealment and internalized homophobia. Identifying and understanding specific LGBTQ+-related minority stress experiences and their complex roles in contributing to mental health burden among LGBTQ+ young adults could inform public health efforts to eliminate mental health inequities experienced by LGBTQ+ young adults. Therefore, this study sought to form empirically based risk profiles (i.e., latent classes) of LGBTQ+ young adults based on their experiences with familial heterosexist experiences, LGBTQ+-related family rejection, internalized LGBTQ+-phobia and LGBTQ+ identity concealment, and then identify associations of derived classes with psychological distress. METHODS: We recruited and enrolled participants using nonprobability, cross-sectional online survey data collected between May and August 2020 (N = 482). We used a three-step latent class analysis (LCA) approach to identify unique classes of response patterns to LGBTQ+-related minority stressor subscale items (i.e., familial heterosexist experiences, LGBTQ+-related family rejection, internalized LGBTQ+-phobia and LGBTQ+ identity concealment), and multinomial logistic regression to characterize the associations between the derived classes and psychological distress. RESULTS: Five distinct latent classes emerged from the LCA: (1) low minority stress, (2) LGBTQ+ identity concealment, (3) family rejection, (4) moderate minority stress and (5) high minority stress. Participants who were classified in the high and moderate minority stress classes were more likely to suffer from moderate and severe psychological distress compared to those classified in the low minority stress class. Additionally, relative to those in the low minority stress class, participants who were classified in the LGBTQ+ identity concealment group were more likely to suffer from severe psychological distress. CONCLUSION: Familial heterosexist experiences, LGBTQ+-related family rejection, internalized LGBTQ+-phobia and LGBTQ+ identity concealment are four constructs that have been extensively examined as predictors for mental health outcomes among LGBTQ+ persons, and our study is among the first to reveal nuanced gradients of these stressors. Additionally, we found that more severe endorsement of minority stress was associated with greater psychological distress. Given our study results and the previously established negative mental health impacts of minority stressors among LGBTQ+ young adults, findings from our study can inform research, practice, and policy reform and development that could prevent and reduce mental health inequities among LGBTQ+ young adults.


Subject(s)
Mental Health , Sexual and Gender Minorities , Female , Humans , Young Adult , United States , Cross-Sectional Studies , Latent Class Analysis , Stress, Psychological/epidemiology , Stress, Psychological/psychology , Gender Identity
4.
Nat Commun ; 15(1): 3658, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38688913

ABSTRACT

Abberent protein-protein interactions potentiate many diseases and one example is the toxic, self-assembly of α-Synuclein in the dopaminergic neurons of patients with Parkinson's disease; therefore, a potential therapeutic strategy is the small molecule modulation of α-Synuclein aggregation. In this work, we develop an Oligopyridylamide based 2-dimensional Fragment-Assisted Structure-based Technique to identify antagonists of α-Synuclein aggregation. The technique utilizes a fragment-based screening of an extensive array of non-proteinogenic side chains in Oligopyridylamides, leading to the identification of NS132 as an antagonist of the multiple facets of α-Synuclein aggregation. We further identify a more cell permeable analog (NS163) without sacrificing activity. Oligopyridylamides rescue α-Synuclein aggregation mediated Parkinson's disease phenotypes in dopaminergic neurons in early and post disease Caenorhabditis elegans models. We forsee tremendous potential in our technique to identify lead therapeutics for Parkinson's disease and other diseases as it is expandable to other oligoamide scaffolds and a larger array of side chains.


Subject(s)
Caenorhabditis elegans , Dopaminergic Neurons , Parkinson Disease , alpha-Synuclein , alpha-Synuclein/metabolism , alpha-Synuclein/genetics , Caenorhabditis elegans/metabolism , Parkinson Disease/metabolism , Parkinson Disease/drug therapy , Parkinson Disease/pathology , Animals , Humans , Dopaminergic Neurons/metabolism , Dopaminergic Neurons/drug effects , Dopaminergic Neurons/pathology , Phenotype , Protein Aggregates/drug effects , Disease Models, Animal , Protein Aggregation, Pathological/metabolism , Protein Aggregation, Pathological/drug therapy , Pyridines/pharmacology , Pyridines/chemistry , Amides/pharmacology , Amides/chemistry
5.
Article in English | MEDLINE | ID: mdl-38514967

ABSTRACT

OBJECTIVE: Anchoring the fetal membrane to the uterine wall via a novel suture delivery system could reduce the risk of preterm premature rupture of membranes (PPROM) after fetoscopic surgery. This study assesses the feasibility of using a novel device designed for minimally invasive suturing to anchor fetal membranes to the uterine wall and to close surgical defects after fetoscopy. METHODS: We tested the suturing device both ex vivo and in vivo. In the ex vivo studies, 12-French trocar defects were created with a fetoscope in five specimens of human uterine tissue with fetal membranes attached. Specimens were examined for integrity of the anchoring stitch. For in vivo studies, trocar defects were created in the two uterine horns of three pregnant ewes, each carrying twins at ~79-90 days gestation. One trocar defect in each ewe was repaired using the suture device, and the other was left unrepaired as a control. The repair sites were examined for membrane anchoring integrity when the defect was created and at delivery. RESULTS: Fetal membranes were successfully anchored to the uterine myometrium using this device in all five trials performed ex vivo. The in vivo trials also revealed successful membrane anchoring compared with controls both at the time of device deployment and five-to-eight weeks after the procedure. CONCLUSIONS: We successfully anchored amniotic membranes to the underlying myometrium via suturing device both ex vivo and in vivo. Further studies are needed to evaluate the efficacy of the device and to determine whether it can successfully anchor fetal membranes percutaneously in human subjects. This article is protected by copyright. All rights reserved.

6.
Br Poult Sci ; : 1-8, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38507293

ABSTRACT

1. In many countries, eggs are not refrigerated and must be stored at room temperature. The objective of this study was to explore the effects of dietary oregano oil (275 mg/kg; ORE) versus an unsupplemented control diet (CON) on laying hens on the shelf life and fatty acid profile of eggs.2. Treatments were randomly distributed into 10 pens containing 27 birds each. A total of 200 eggs were collected from both groups on the same day and were stored for either 0, 10, 21 and 35 d. At each storage time, egg yolks were analysed for fatty acid profile and lipid peroxidation.3. The main indicator of lipid peroxidation, malondialdehyde (MDA), was significantly lower in ORE eggs compared to CON eggs (p = 0.001). Storage time had a significant impact on MDA concentrations (p = 0.023), with the highest found after 35 d. Significant differences were found for individual fatty acids, saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA). Palmitic acid, stearic acid, oleic acid, linoleic acid and arachidonic acid were significantly lower in ORE eggs compared to CON eggs (p < 0.05). Palmitoleic acid (p = 0.002), linolenic acid (p = 0.001) and docosahexaenoic acid (DHA, p = 0.001) were significantly higher in ORE eggs.4. Storage only affected oleic, linolenic, linoleic, arachidonic and docosahexaenoic acids (p < 0.05). Total SFA, MUFA, n-6 and ratio of n-3 to n-6 (n-3:n-6) PUFA were significantly higher in CON eggs (p < 0.05). The ratio of SFA to PUFA (SFA:PUFA, p = 0.005) and total n-3 PUFA (p = 0.001) were significantly higher in ORE eggs.5. The n-3:n-6 ratio was significantly impacted by treatment (p = 0.021) and storage (p = 0.031) with no significant interaction. This ratio is important for human health indication and could lead to the development of designer eggs.

7.
Article in English | MEDLINE | ID: mdl-38437460

ABSTRACT

OBJECTIVE: To determine the association of high middle cerebral artery peak systolic velocity (MCA-PSV) with fetal demise in donor twins among pregnancies complicated by twin-to-twin transfusion syndrome (TTTS) in the absence of twin anemia polycythemia sequence (TAPS). METHODS: This prospective cohort study included TTTS cases that underwent laser surgery between 2011 and 2022 at a single center. TAPS cases were excluded from the study. The primary objective was to explore the association of high MCA-PSV (>1.5 multiples of the median) with fetal demise of the donor twin among pregnancies complicated by TTTS. Secondary objectives were: 1) to evaluate if donor or recipient MCA-PSV is associated with an increased risk for their corresponding fetal death using receiving operator characteristic curve analysis; and 2) to compare the proportion of fetuses with low MCA pulsatility index among donor twins with high MCA-PSV and in those with normal MCA-PSV to evaluate the contribution of blood flow redistribution to high MCA-PSV. Multivariable and Poisson regression analysis were performed to explore the association of isolated high donor MCA-PSV and fetal demise, adjusted for TTTS stage, selective fetal growth restriction (sFGR), and other confounders. p<0.05 was considered significant. RESULTS: Out of 660 TTTS cases, donor MCA-PSV was unavailable in 48 (7.3%) cases. Of the remaining 612 patients, 9 (1.5%) were lost to follow-up, and 96 TAPS cases were excluded. High donor MCA-PSV was seen in 6.5% (33/507) of the study population. High donor MCA-PSV was an independent risk factor for donor fetal demise (adjusted relative risk (aRR) of 4.52; 95% CI: 2.72-7.50), adjusted for confounders. Regression analysis restricted to each Quintero TTTS stage demonstrated that high donor MCA-PSV was an independent risk factor for donor fetal demise in Quintero stage II (aRR of 14.21; 95% CI: 1.09-186.2) and Quintero stage III (aRR of 3.41; 95% CI: 1.82-6.41). Donor MCA-PSV was associated with donor fetal demise (AUC: 0.69; p<0.001), but recipient MCA-PSV was not associated with its corresponding fetal demise (AUC: 0.54; p=0.44). A higher proportion of donor twins in the group with high MCA-PSV had a low MCA pulsatility index than in those with normal MCA-PSV (33.3% vs. 15.5%; p=0.016). CONCLUSIONS: Elevated donor MCA-PSV without TAPS prior to laser surgery is associated with a 4-fold increased risk for donor fetal demise, adjusted for sFGR, TTTS stage, and other confounders. Doppler evaluation of donor MCA-PSV prior to laser surgery can further stratify TTTS staging to evaluate the risk for donor fetal demise. This article is protected by copyright. All rights reserved.

8.
Foot Ankle Int ; 45(3): 252-260, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38281125

ABSTRACT

BACKGROUND: Flatfoot deformity is believed to play a role in hallux valgus development and recurrence. While symptomatic flatfoot deformity can be treated with separate procedures at the time of hallux valgus correction, the question remains whether the patient undergoing correction of a symptomatic hallux valgus deformity should have their asymptomatic flatfoot concurrently addressed. We aimed to investigate whether the presence of asymptomatic flatfoot influences patient-reported and radiographic outcomes of the minimally invasive chevron and Akin bunionectomy. METHODS: A total of 104 patients were included in this study. Forty-two asymptomatic patients met the radiographic criteria for flatfoot while 62 had a normal arch. Patient-reported outcomes were evaluated and compared between the two groups using validated PROMIS measures preoperatively and at a minimum one-year postoperatively. Radiographic outcomes including hallux valgus angle (HVA), intermetatarsal angle (IMA), Meary's angle, calcaneal pitch (CP), and talonavicular coverage angle (TNCA) were measured and compared preoperatively and minimum six-months postoperatively. RESULTS: Both groups demonstrated similar preoperative and postoperative PROMIS scores with significant improvements in physical function, pain interference, pain intensity, and global physical health. Preoperatively, HVA was similar between both groups, however the flatfoot group showed a greater IMA, Meary's angle, TNCA, and lower CP. Postoperatively, HVA and IMA were similar between groups, although patients in the flatfoot group retained a significantly greater Meary's angle, TNCA, and lower CP. Both groups showed significant improvements in HVA, IMA, and TNCA. CONCLUSION: Our study indicates that the minimally invasive chevron and Akin bunionectomy leads to improved clinical and radiographic hallux valgus outcomes without adversely impacting radiographic flatfoot parameters. Therefore, the MIS bunionectomy may be an effective option for hallux valgus correction in patients with mild, asymptomatic flatfoot. LEVEL OF EVIDENCE: Level III, retrospective cohort.


Subject(s)
Bunion , Flatfoot , Hallux Valgus , Humans , Retrospective Studies , Hallux Valgus/diagnostic imaging , Hallux Valgus/surgery , Flatfoot/diagnostic imaging , Flatfoot/surgery , Osteotomy/methods , Radiography , Treatment Outcome
9.
Article in English | MEDLINE | ID: mdl-38207160

ABSTRACT

OBJECTIVE: Laparotomy-assisted fetoscopic closure of spina bifida utilizing heated-humidified carbon dioxide gas has been associated with less maternal morbidity than open in-utero spina bifida closure. Fetal cardiovascular changes during these surgical interventions are not well defined. Our objective was to compare fetal bradycardia (defined as fetal heart rate (FHR)<110 bpm over 10 minutes) and changes in umbilical artery Doppler parameters throughout open in-utero closure with those observed during laparotomy-assisted fetoscopic closure. METHODS: We conducted a prospective cohort study of 22 open and 46 fetoscopic consecutive in-utero closures between 2019 and 2023. Both cohorts had similar preoperative counseling and clinical management. FHR and umbilical artery velocimetry were systematically obtained during preoperative assessment, every 5 minutes during the intraoperative period, and in the postoperative assessment. FHR, pulsatility indexes and end-diastolic flows were segmented into hourly periods during surgery, and the lowest values were averaged for analysis. Umbilical vein maximum velocities were measured in the fetoscopic cohort. Each fetal heart rate recording time point was correlated to maternal parameters, including heart rate, systolic and diastolic blood pressures. RESULTS: Fetal bradycardia occurred in 4/22 cases (18.2%) of open in-utero closure and in 21/46 cases (45.7%) of fetoscopic closure. FHR gradually decreased in both cohorts after general anesthesia and decreased further during surgery. FHR were significantly lower after two hours of surgery in the fetoscopic closure than in the open in-utero closure group. In addition, the FHR (BPM) change in the final stages of the fetal surgery from the baseline FHR was significantly lower in the fetoscopic cohort (-32.3 (-35.7, -29.1)) compared to the open cohort (-23.5 (-28.1, -18.8)) (p=0.002). Abnormal end-diastolic flow (defined as absent or reversed end-diastolic flow) in the umbilical artery Doppler velocity occurred in 3/22 (13.6%) of the open closure cohort and in 23/46 (50%) of the fetoscopic closure cohort (p=0.004). There were no differences in umbilical artery end-diastolic flow and pulsatility index between closure techniques during the various stages of assessment. CONCLUSIONS: We observed a decrease in the FHR and abnormalities in umbilical artery Doppler parameters in both open in-utero and fetoscopic closure groups. Fetal bradycardia was more prominent during fetoscopic closure following heated-humidified carbon dioxide insufflation, but the FHR recovered after cessation of the heated-humidified carbon dioxide. Changes in FHR and umbilical artery Doppler parameters during in-utero spina bifida closure were observed to be transient, no cases required emergency delivery and no fetoscopic closure were converted to open closure. These observations should inform algorithms for perioperative management of fetal bradycardia associated with in-utero spina bifida closure. This article is protected by copyright. All rights reserved.

10.
Health Res Policy Syst ; 22(1): 4, 2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38178086

ABSTRACT

Despite forming the cornerstone of modern clinical practice for decades, implementation of evidence-based medicine at scale remains a crucial challenge for health systems. As a result, there has been a growing need for conceptual models to better contextualise and pragmatize the use of evidence-based medicine, particularly in tandem with patient-centred care. In this commentary, we highlight the emergence of the learning health system as one such model and analyse its potential role in pragmatizing both evidence-based medicine and patient-centred care. We apply the learning health system lens to contextualise the key activity of evidence-based guideline development and implementation, and highlight how current inefficiencies and bottlenecks in the evidence synthesis phase of evidence-based guideline development threaten downstream adherence. Lastly, we introduce the evidence ecosystem as a complementary model to learning health systems, and propose how innovative developments from the evidence ecosystem may be integrated with learning health systems to better enable health impact at speed and scale.


Subject(s)
Evidence-Based Medicine , Learning Health System , Humans , Ecosystem
11.
Ultrasound Obstet Gynecol ; 63(3): 371-377, 2024 03.
Article in English | MEDLINE | ID: mdl-37553800

ABSTRACT

OBJECTIVE: Fetoscopic laser photocoagulation (FLP) is a well-established treatment for twin-twin transfusion syndrome (TTTS) between 16 and 26 weeks' gestation. High-quality evidence and guidelines regarding the optimal clinical management of very early (prior to 16 weeks), early (between 16 and 18 weeks) and late (after 26 weeks) TTTS are lacking. The aim of this study was to construct a structured expert-based clinical consensus for the management of early and late TTTS. METHODS: A Delphi procedure was conducted among an international panel of experts. Participants were chosen based on their clinical expertise, affiliation and relevant publications. A four-round Delphi survey was conducted using an online platform and responses were collected anonymously. In the first round, a core group of experts was asked to answer open-ended questions regarding the indications, timing and modes of treatment for early and late TTTS. In the second and third rounds, participants were asked to grade each statement on a Likert scale (1, completely disagree; 5, completely agree) and to add any suggestions or modifications. At the end of each round, the median score for each statement was calculated. Statements with a median grade of 5 without suggestions for change were accepted as the consensus. Statements with a median grade of 3 or less were excluded from the Delphi process. Statements with a median grade of 4 were modified according to suggestions and reconsidered in the next round. In the last round, participants were asked to agree or disagree with the statements, and those with more than 70% agreement without suggestions for change were considered the consensus. RESULTS: A total of 122 experts met the inclusion criteria and were invited to participate, of whom 53 (43.4%) agreed to take part in the study. Of those, 75.5% completed all four rounds. A consensus on the optimal management of early and late TTTS was obtained. FLP can be offered as early as 15 weeks' gestation for selected cases, and can be considered up to 28 weeks. Between 16 and 18 weeks, management should be tailored according to Doppler findings. CONCLUSIONS: A consensus-based treatment protocol for early and late TTTS was agreed upon by a panel of experts. This protocol should be modified at the discretion of the operator, according to their experience and the specific demands of each case. This should advance the quality of future studies, guide clinical practice and improve patient care. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Fetofetal Transfusion , Gynecology , Female , Pregnancy , Humans , Consensus , Delphi Technique , Fetofetal Transfusion/diagnostic imaging , Fetofetal Transfusion/surgery , Fetoscopy
12.
Neurobiol Stress ; 28: 100590, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38075024

ABSTRACT

Introduction: Behavioral therapies, including cognitive behavioral therapy, hypnotherapy and stress management activities, have emerged as effective treatments for irritable bowel syndrome (IBS), a female predominant disorder of the brain-gut axis. IBS, affecting over 10% of the global population, typically presents with abnormal bowel habits and abdominal pain due to visceral hypersensitivity. While the mechanisms underlying how behavioral therapies treat IBS are still elusive, we had previously shown that chronic stress alters gene expression in brain regions critical for stress processing and nociception. We found that exposure to an enriched environment (EE), the rodent analogue of behavioral therapies, prior to and during the stressor was sufficient to prevent stress-induced changes in glucocorticoid receptor (GR) expression in the central nucleus of the amygdala (CeA) and hippocampus. Pre-exposure to EE also inhibited stress-induced increased colonic permeability and was able to block the induction of stress-induced visceral and somatic hypersensitivity. However, it remains unknown if EE can reverse chronic viscerosomatic hypersensitivity that persists following exposure to stress. We hypothesized that EE after chronic stress would be sufficient to reverse stress-induced changes in i) GR expression in the CeA and hippocampus, ii) ameliorate stress-induced colonic hyperpermeability and iii) restore normal visceral and somatic sensitivity in male and female rats. Methods: Male and female rats were exposed to daily water avoidance stress (WAS). After confirming the rats had developed visceral hypersensitivity, 50% of the animals were housed in EE for 2 weeks while the other 50% remained in standard housing (SH). At the end of this period, we assessed visceral and somatic sensitivity. We also collected colon tissue to measure colonic permeability. Micro-punches of tissue from the CeA and hippocampus were isolated to measure GR expression. Control animals not exposed to WAS were kept in SH for the duration of the study (n = 8 per group). Results: In both male and female rats, EE reversed stress-induced visceral (p < 0.001) and somatic (p < 0.01) hypersensitivity when compared to WAS animals housed in SH to levels comparable to control animals. EE exposure also reversed changes in GR expression in both the hippocampus (p < 0.01) and CeA (p < 0.01), normalizing GR expression to control levels. EE exposure ameliorated stress-induced colonic hyperpermeability in both male (p < 0.01) and female (p < 0.01) rats compared to WAS rats in SH. Conclusion: Our findings suggest that behavioral therapies are viable therapeutic options for IBS as they can counter the stress-induced pathophysiology underlying IBS symptoms including visceral hypersensitivity, increased colonic permeability and altered gene expression.

13.
Life Sci Space Res (Amst) ; 39: 67-75, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37945091

ABSTRACT

We report the results of the first six years of measurements of the energetic particle radiation environment on the International Space Station (ISS) with the Radiation Assessment Detector (ISS-RAD), spanning the period from February 2016 to February 2022. The first RAD was designed and built for MSL, the Mars Science Laboratory rover, also known as Curiosity; it has been operating on Mars since 2012 and is referred to here as MSL-RAD. ISS-RAD combines two sensor heads, one nearly identical to the single MSL-RAD sensor head, the other with greatly enhanced sensitivity to fast neutrons. These two sensor heads are referred to as the Charged Particle Detector (CPD) and Fast Neutron Detector (FND), respectively. Despite its name, the CPD is also capable of measuring high-energy neutrons and γ-rays, as is MSL-RAD. ISS-RAD was flown to the ISS in December 2015 and was deployed in February 2016, initially in the USLab module. RAD was used as a survey instrument from January 2017 through May 2020, when the instrument was positioned in the USLab and set to a zenith-pointing orientation. The energetic particle environment on the ISS is complex and varies on short time scales owing to the orbit, which has a 51.6∘ inclination with respect to the equator and has had an altitude in the 400-440 km range in this time period. The ISS moves continuously through the geomagnetic field, the strength of which varies with latitude, longitude, and altitude. The orbit passes through the South Atlantic Anomaly (SAA) several times a day, where magnetically trapped protons and electrons produce large but transient increases in observed fluxes and absorbed dose rates. The environment inside the ISS is affected by the solar cycle, altitude, and the local shielding, which varies between different ISS modules. We report results for charged particle absorbed dose and dose equivalent rates in various positions in the ISS. In an accompanying paper, we report similar results for neutron dose equivalent rates obtained with the ISS-RAD Fast Neutron Detector.


Subject(s)
Cosmic Radiation , Radiation Monitoring , Radiation Protection , Radiation Monitoring/methods , Neutrons , Protons
14.
Life Sci Space Res (Amst) ; 39: 76-85, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37945092

ABSTRACT

We report the results of the first six years of measurements of so-called fast neutrons on the International Space Station (ISS) with the Radiation Assessment Detector (ISS-RAD), spanning the period from February 2016 to February 2022. ISS-RAD combines two sensor heads, one nearly identical to the single sensor head in the Mars Science Laboratory RAD (MSL-RAD). The latter is described in a companion article to this one. The novel sensor is the FND, or fast neutron detector, designed to measure neutrons with energies in the range from 200 keV to about 8 MeV. ISS-RAD was deployed in February 2016 in the USLAB module, and then served as a survey instrument from March 2017 until May 2020. Data were acquired in Node3, the Japanese Pressurized Module, Columbus, and Node2. At the conclusion of the survey portion of RAD's planned 10-year campaign on ISS, the instrument was stationed in the USLAB; current plans call for it to remain there indefinitely. The radiation environment on the ISS consists of a complex mix of charged and neutral particles that varies on short time scales owing to the Station's orbit. Neutral particles, and neutrons in particular, are of concern from a radiation protection viewpoint, because they are both highly penetrating (since they do not lose energy via direct ionization) and, at some energies, have high biological effectiveness. Neutrons are copiously produced by GCRs and other incident energetic particles when they undergo nuclear interactions in shielding. As different ISS modules have varying amounts of shielding, they also have varying neutron environments. We report results for neutron fluences and dose equivalent rates in various positions in the ISS.


Subject(s)
Cosmic Radiation , Radiation Monitoring , Space Flight , Spacecraft , Fast Neutrons , Radiation Monitoring/methods , Neutrons , Radiation Dosage
15.
Life Sci Space Res (Amst) ; 39: 86-94, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37945093

ABSTRACT

The energetic particle radiation environment on the International Space Station (ISS) includes both charged and neutral particles. Here, we make use of the unique capabilities of the Radiation Assessment Detector (ISS-RAD) to measure both of these components simultaneously. The Charged Particle Detector (CPD) is, despite its name, capable of measuring neutrons in the energy range from about 4 MeV to a few hundred MeV. Combined with data from the Fast Neutron Detector (FND) in the 0.2 to 8 MeV range, we present the first broad-spectrum measurements of the neutron environments in various locations within the ISS since an early Bonner-Ball experiment that was conducted before the Station was fully constructed. The data presented here span the time period from February 2016 to February 2022. In addition to presenting broad-spectrum neutron fluence measurements, we show correlations of the measured neutron dose equivalent with charged-particle dose rates. The ratio of charged-particle dose to neutron dose equivalent is found to be relatively stable within the ISS.


Subject(s)
Cosmic Radiation , Radiation Monitoring , Fast Neutrons , Spacecraft , Radiation Dosage , Radiation Monitoring/methods , Neutrons
16.
Life Sci Space Res (Amst) ; 39: 95-105, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37945094

ABSTRACT

Monitoring space radiation is of vital importance for risk reduction strategies in human space exploration. Radiation protection programs on Earth and in space rely on personal and area radiation monitoring instruments. Crew worn radiation detectors are crucial for successful crew radiation protection programs since they measure what each crewmember experiences in different shielding configurations within the space habitable volume. The Space Radiation Analysis Group at NASA Johnson Space Center investigated several compact, low power, real-time instruments for personal dosimetry. Following these feasibility studies, the Crew Active Dosimeter (CAD) has been chosen as a replacement for the legacy crew passive radiation detectors. The CAD device, based on direct ion storage technology, was developed by Mirion Dosimetry Services to meet the specified NASA design requirements for the International Space Station (ISS) and Artemis programs. After a successful Technology demonstration on ISS, the CAD has been implemented for ISS Crew operations since 2020. The current paper provides an overview of the CAD development, ISS results and comparison with the ISS Radiation Assessment Detector (RAD) and the Radiation Environment Monitor 2 (REM2) instruments.


Subject(s)
Cosmic Radiation , Radiation Monitoring , Space Flight , Humans , Spacecraft , Radiation Dosimeters , Radiometry , Radiation Monitoring/methods , Radiation Dosage
18.
Theriogenology ; 212: 111-116, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37717514

ABSTRACT

Feline breeding colonies are important to the feline industry by preserving traits desirable for a particular breed or in research settings by maintaining medically valuable genetic traits. As breeding females age, their reproductive efficiency declines. The objective of this study was to determine the most common causes of infertility in breeding females that were producing fewer kittens. Knowing the cause and average age of infertility would allow management decisions to be made for the betterment of the colony. The medical records of 70 queens retired from breeding from a single research colony were examined for litter size and number, fertility over their lifespan, and age and reason for removal from breeding stock. Sections of uterus and ovaries were evaluated using gross and histopathological examination for a subset of these queens (46). The data suggests that mature, continuously breeding female cats may show signs of reduced fertility (infertile matings or reduced litter size) as early as 3 years of age and may be a result of undiagnosed Cystic Endometrial Hyperplasia (CEH), endometritis, pyometra and/or ovarian cysts. Evaluation of breeding queens should include periodic ultrasounds to monitor for ovarian cysts and evidence of CEH. Retiring animals from breeding once signs of infertility become apparent is recommended.

19.
Afr Health Sci ; 23(1): 765-773, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37545953

ABSTRACT

This study investigated the genetic diversity of Plasmodium falciparum among asymptomatic pregnant women on intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-Sp) in Osogbo, southwest Nigeria. Blood sample was obtained from consenting pregnant women attending antenatal clinics. Microscopy and Polymerase chain reaction (PCR) were employed to diagnose and analyse genetic diversity. Of the 301 samples, 53 (18%) and 83 (28%) were positive for P. falciparum by microscopy and PCR, respectively. Using the merozoite surface protein (msp)-1, msp-2, and glutamate-rich protein (glurp) genes of P. falciparum as polymorphic markers, the msp-1 gene showed nine alleles with R033 (66.7%) being predominant, followed by K1 (45.5%) and MAD20 (33.3%). The msp-2 gene had 16 alleles (eight each for FC27 and 3D7). The 3D7 alleles (82.1%) was significantly more than FC27 alleles (48.2%) (p = 0.0093). Nine alleles were detected with glurp gene, presenting with the highest monoclonal and the lowest polyclonal infection. The multiplicity of infection (MOI) of 1.5, 1.8, and 1.2 were obtained for msp-1, msp-2 and glurp genes. In light of the high P. falciparum genetic diversity among pregnant women on IPT-Sp in this study, additional strategies for preventing and controlling malaria in pregnancy might be required.


Subject(s)
Malaria, Falciparum , Plasmodium falciparum , Pregnancy , Female , Humans , Plasmodium falciparum/genetics , Merozoite Surface Protein 1/genetics , Protozoan Proteins/genetics , Antigens, Protozoan/genetics , Genetic Variation , Pregnant Women , Nigeria/epidemiology , Malaria, Falciparum/epidemiology , Malaria, Falciparum/prevention & control , Genotype
20.
J Hosp Infect ; 140: 24-33, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37532196

ABSTRACT

BACKGROUND: Point prevalence surveys are an important surveillance method for determining the burden of healthcare-associated infections (HCAIs). AIM: To outline the key results of two point prevalence surveys in England (2011 and 2016). METHODS: All National Health Service and independent sector hospitals in England were eligible to participate. Data were collected between September and November in both 2011 and 2016 based on the protocol and codebook devised by the European Centre for Disease Prevention and Control. Analysis was performed using Stata Version 13 and SAS Version 9.3. A mixed-effects model was applied, which allowed estimation of organization-specific means and accounted for the heterogeneity in the responses from different organizations. FINDINGS: A total of 100,755 case records were included (52,433 in 2011 and 48,312 in 2016). The estimated prevalence of HCAIs was slightly higher in 2016 [6.89%, 95% confidence interval (CI) 6.21-7.57%] than in 2011 (6.41%, 95% CI 5.75-7.06%). In both surveys, the prevalence of HCAIs was highest in adult intensive care units (23.1% in 2011, 21.2% in 2016), and pneumonia/lower respiratory tract infections was the most common cause of HCAIs (22.7% in 2011 vs 29.2% in 2016). Inpatients in acute hospitals were older and had higher risk of dying in 2016 compared with 2011; however, the proportion of inpatients with HCAIs or on antibiotics did not differ significantly. CONCLUSION: The burden of HCAIs in English hospitals increased slightly between 2011 and 2016. However, the proportion of inpatients with HCAIs or on antibiotics did not differ significantly.


Subject(s)
Cross Infection , State Medicine , Adult , Humans , Prevalence , Cross Infection/epidemiology , Anti-Bacterial Agents , England/epidemiology
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