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1.
Bone Rep ; 21: 101761, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38646090

ABSTRACT

Spinal cord injury (SCI) leads to significant sublesional bone loss and high fracture rates. While loss of mechanical loading plays a significant role in SCI-induced bone loss, animal studies have demonstrated mechanical loading alone does not fully account for loss of bone following SCI. Indeed, we have shown that bone loss occurs below the level of an incomplete moderate contusion SCI, despite the resumption of weight-bearing and stepping. As systemic factors could also impact bone after SCI, bone alterations may also be present in bone sites above the level of injury. To examine this, we assessed bone microarchitecture and bone turnover in the supralesional humerus in male and female rats at two different ages following a moderate contusion injury in both sub-chronic (30 days) and chronic (180 days) time points after injury. At the 30-day timepoint, we found that both young and adult male SCI rats had decrements in trabecular bone volume at the supralesional proximal humerus (PH), while female SCI rats were not different from age-matched shams. At the 180-day timepoint, there were no statistical differences between SCI and sham groups, irrespective of age or sex, at the supralesional proximal humerus. At the 30-day timepoint, all SCI rats had lower BFR and higher osteoclast-covered trabecular surfaces in the proximal humerus compared to age-matched sham groups generally matching the pattern of SCI-induced changes in bone turnover seen in the sublesional proximal tibia. However, at the 180-day timepoint, only male SCI rats had lower BFR at the supralesional proximal humerus while female SCI rats had higher or no different BFR than their age-matched counterparts. Overall, this preclinical study demonstrates that a moderate contusion SCI leads to alterations in bone turnover above the level of injury within 30-days of injury; however male SCI rats maintained lower BFR in the supralesional humerus into long-term recovery. These data further highlight that bone loss after SCI is not driven solely by disuse. Additionally, these data allude to potential systemic factors exerting influence on bone following SCI and highlight the need to consider treatments for SCI-induced bone loss that impact both sublesional and systemic factors.

2.
AJP Rep ; 10(4): e395-e402, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33294284

ABSTRACT

Objective To describe our hospital's experience following expectant management of previable preterm prelabor rupture of membranes (pPPROM). Study Design Retrospective review of neonatal survival and maternal and neonatal outcomes of pPPROM cases between 2012 and 2019 at a tertiary referral center in South Central Louisiana. Regression analyses were performed to identify predictors of neonatal survival. Results Of 81 cases of pPPROM prior to 23 weeks gestational age (WGA), 23 survived to neonatal intensive care unit discharge (28.3%) with gestational age at rupture ranging from 18 0/7 to 22 6/7 WGA. Increased latency (adjusted odds ratio [aOR] = 1.30, 95% confidence interval [CI] = 1.11, 1.52) and increased gestational age at rupture (aOR = 1.62, 95% CI = 1.19, 2.21) increased the probability of neonatal survival. Antibiotics prior to delivery were associated with increased latency duration (adjusted hazard ratio = 0.55, 95% CI = 0.42, 0.74). Conclusion Neonatal survival rate following pPPROM was 28.3%. Later gestational age at membrane rupture and increased latency periods are associated with increased neonatal survivability. Antibiotic administration following pPPROM increased latency duration.

3.
Sci Total Environ ; 716: 132849, 2020 May 10.
Article in English | MEDLINE | ID: mdl-32057506

ABSTRACT

The objective of this review is to evaluate materials for use as a barrier or other deployed technology to treat technetium-99 (Tc) in the subsurface. To achieve this, Tc interactions with different materials are considered within the context of remediation strategies. Several naturally occurring materials are considered for Tc immobilization, including iron oxides and low solubility sulfide phases. Synthetic materials are also considered, and include tin-based materials, sorbents (resins, activated carbon, modified clays), layered double hydroxides, metal organic frameworks, cationic polymeric networks and aerogels. All of the materials were evaluated for their potential in-situ and ex-situ performance with respect to long-term Tc uptake and immobilization, environmental impacts and deployability. Other factors such as the technology maturity, cost and availability were also considered. Given the difficulty of evaluating materials under different experimental conditions (e.g., solution chemistry, redox conditions, solution to solid ratio, Tc concentration etc.), a subset of these materials will be selected, on the basis of this review, for subsequent standardized batch loading tests.

4.
Sci Total Environ ; 716: 136167, 2020 May 10.
Article in English | MEDLINE | ID: mdl-31955840

ABSTRACT

Radioactive iodine-129 (129I) and technetium-99 (99Tc) pose a risk to groundwater due to their long half-lives, toxicity, and high environmental mobility. Based on literature reviewed in Moore et al. (2019) and Pearce et al. (2019), natural and engineered materials, including iron oxides, low-solubility sulfides, tin-based materials, bismuth-based materials, organoclays, and metal organic frameworks, were tested for potential use as a deployed technology for the treatment of 129I and 99Tc to reduce environmental mobility. Materials were evaluated with metrics including capacity for IO3- and TcO4- uptake, selectivity and long-term immobilization potential. Batch testing was used to determine IO3- and TcO4- sorption under aerobic conditions for each material in synthetic groundwater at different solution to solid ratios. Material association with IO3- and TcO4- was spatially resolved using scanning electron microscopy and X-ray microprobe mapping. The potential for redox reactions was assessed using X-ray absorption near edge structure spectroscopy. Of the materials tested, bismuth oxy(hydroxide) and ferrihydrite performed the best for IO3-. The commercial Purolite A530E anion-exchange resin outperformed all materials in its sorption capacity for TcO4-. Tin-based materials had high capacity for TcO4-, but immobilized TcO4- via reductive precipitation. Bismuth-based materials had high capacity for TcO4-, though slightly lower than the tin-based materials, but did not immobilize TcO4- by a redox-drive process, mitigating potential negative re-oxidation effects over longer time periods under oxic conditions. Cationic metal organic frameworks and polymer networks had high Tc removal capacity, with TcO4- trapped within the framework of the sorbent material. Although organoclays did not have the highest capacity for IO3- and TcO4- removal in batch experiments, they are available commercially in large quantities, are relatively low cost and have low environmental impact, so were investigated in column experiments, demonstrating scale-up and removal of IO3- and TcO4- via sorption, and reductive immobilization with iron- and sulfur-based species.

5.
Sci Total Environ ; 716: 132820, 2020 May 10.
Article in English | MEDLINE | ID: mdl-31982189

ABSTRACT

Radioiodine-129 (129I) in the subsurface is mobile and limited information is available on treatment technologies. Scientific literature was reviewed to compile information on materials that could potentially be used to immobilize 129I through sorption and redox-driven processes, with an emphasis on ex-situ processes. Candidate materials to immobilize 129I include iron minerals, sulfur-based materials, silver-based materials, bismuth-based materials, ion exchange resins, activated carbon, modified clays, and tailored materials (metal organic frameworks (MOFS), layered double hydroxides (LDHs) and aerogels). Where available, compiled information includes material performance in terms of (i) capacity for 129I uptake; (ii) long-term performance (i.e., solubility of a precipitated phase); (iii) technology maturity; (iv) cost; (v) available quantity; (vi) environmental impact; (vii) ability to emplace the technology for in situ use at the field-scale; and (viii) ex situ treatment (for media extracted from the subsurface or secondary waste streams). Because it can be difficult to compare materials due to differences in experimental conditions applied in the literature, materials will be selected for subsequent standardized batch loading tests.

6.
Nat Commun ; 10(1): 257, 2019 01 16.
Article in English | MEDLINE | ID: mdl-30651535

ABSTRACT

Chorus waves, among the most intense electromagnetic emissions in the Earth's magnetosphere, magnetized planets, and laboratory plasmas, play an important role in the acceleration and loss of energetic electrons in the plasma universe through resonant interactions with electrons. However, the spatial evolution of the electron resonant interactions with electromagnetic waves remains poorly understood owing to imaging difficulties. Here we provide a compelling visualization of chorus element wave-particle interactions in the Earth's magnetosphere. Through in-situ measurements of chorus waveforms with the Arase satellite and transient auroral flashes from electron precipitation events as detected by 100-Hz video sampling from the ground, Earth's aurora becomes a display for the resonant interactions. Our observations capture an asymmetric spatial development, correlated strongly with the amplitude variation of discrete chorus elements. This finding is not theoretically predicted but helps in understanding the rapid scattering processes of energetic electrons near the Earth and other magnetized planets.

7.
Ochsner J ; 16(4): 542-544, 2016.
Article in English | MEDLINE | ID: mdl-27999514

ABSTRACT

BACKGROUND: Stroke in the pregnant patient is not a common occurrence. Despite its relative rarity, stroke during pregnancy is associated with high morbidity and mortality for both mother and infant. We report the case of a patient who experienced a hemorrhagic stroke during pregnancy because of venous cavernoma. CASE REPORT: A 34-year-old patient, gravida 5 para 1-0-3-1, presented to labor and delivery triage at 21 weeks, 0 days' gestation with the concern of sudden-onset right-sided facial, arm, and leg numbness and weakness. Intracranial imaging via magnetic resonance imaging demonstrated a small left midbrain venous cavernoma in the periaqueductal region of the posterior lateral cerebral peduncle area with evidence of edema and focal hemorrhage. During a 3-day hospital admission, the patient's deficits slowly improved, and she was discharged home. She subsequently delivered vaginally without incident. Six days postpartum, the patient presented with symptoms that were similar to her initial presentation. She was correctly diagnosed with migraine with aura after the appropriate neuroimaging studies did not show an acute stroke. CONCLUSION: This case demonstrates the similarities between the perilous diagnosis of stroke and the more routine diagnosis of migraine. The case also highlights the need for caution and for a multidisciplinary treatment approach when the diagnosis of stroke is considered, particularly in the pregnant patient.

8.
Am J Perinatol ; 33(12): 1218-22, 2016 10.
Article in English | MEDLINE | ID: mdl-27631601

ABSTRACT

Objective We aimed to determine if fibroids in pregnancy, categorized by size, are associated with adverse obstetrical outcomes. Study Design Demographic, clinical, and delivery data were collected from charts of women with singleton gestations who delivered at >20 weeks gestation with fibroids identified at routine anatomy scan and their randomly selected age-matched controls. Largest fibroid diameter was used to categorize small fibroids (≤5 cm) and large fibroids (>5 cm). Results We included 450 patients: 264 patients with fibroids (174 small, 90 large fibroids) and 186 age-matched controls. Women with large fibroids had significantly greater blood loss than women with small fibroids and women with no fibroids (p-value <0.0001 and <0.0001 after adjusting for delivery mode). When fibroid size was compared individually, there was a significantly higher rate of primary cesarean section in both small and large fibroid groups when compared with women with no fibroids (p-values 0.044 and 0.003 after adjusting for body mass index). Conclusion Women with fibroids in pregnancy have higher rates of primary cesarean delivery and are at significant risk for increased blood loss at the time of delivery.


Subject(s)
Cesarean Section/statistics & numerical data , Leiomyoma/diagnostic imaging , Postpartum Hemorrhage/etiology , Pregnancy Complications, Neoplastic/diagnostic imaging , Uterine Neoplasms/diagnostic imaging , Adult , Blood Volume , Case-Control Studies , Female , Gestational Age , Humans , Leiomyoma/complications , Leiomyoma/pathology , Pregnancy , Pregnancy Complications, Neoplastic/pathology , Tumor Burden , Uterine Neoplasms/complications , Uterine Neoplasms/pathology
9.
Environ Pollut ; 218: 1102-1107, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27592077

ABSTRACT

The sorption of selenite, SeO32-, by carbonate substituted hydroxylapatite was investigated using batch kinetic and equilibrium experiments. The carbonate substituted hydroxylapatite was prepared by a precipitation method and characterized by SEM, XRD, FT-IR, TGA, BET and solubility measurements. The material is poorly crystalline, contains approximately 9.4% carbonate by weight and has a surface area of 210.2 m2/g. Uptake of selenite by the carbonated hydroxylapatite was approximately an order of magnitude higher than the uptake by uncarbonated hydroxylapatite reported in the literature. Distribution coefficients, Kd, determined for the carbonated apatite in this work ranged from approximately 4200 to over 14,000 L/kg. A comparison of the results from kinetic experiments performed in this work and literature kinetic data indicates the carbonated apatite synthesized in this study sorbed selenite 23 times faster than uncarbonated hydroxylapatite based on values normalized to the surface area of each material. The results indicate carbonated apatite is a potential candidate for use as a sorbent for pump-and-treat technologies, soil amendments or for use in permeable reactive barriers for the remediation of selenium contaminated sediments and groundwaters.


Subject(s)
Apatites/chemistry , Selenious Acid/chemistry , Adsorption , Kinetics , Solubility , Spectroscopy, Fourier Transform Infrared
10.
Clin Colon Rectal Surg ; 23(2): 80-9, 2010 Jun.
Article in English | MEDLINE | ID: mdl-21629625

ABSTRACT

Pregnancy causes anatomic and physiologic changes in the gastrointestinal tract. Pregnant women with intestinal disease such as Crohn disease or ulcerative colitis pose a management challenge in clinical diagnosis, radiologic evaluation, and treatment secondary to potential risk to the fetus. Heightened physician awareness on possible etiologies such as appendicitis, diverticulitis, and rarely colorectal cancer is required for rapid diagnosis and treatment to improve maternal/fetal outcome. A multidisciplinary approach to evaluation is a necessity because radiologic procedures and treatment medications commonly used in nonpregnant patients may have a potential harmful effect on the fetus. The authors review several gastrointestinal conditions encountered during pregnancy and address presentation, diagnosis, and treatment of each condition.

11.
Carbohydr Res ; 340(13): 2195-200, 2005 Sep 26.
Article in English | MEDLINE | ID: mdl-16043161

ABSTRACT

Ammonium D-glucarate, NH(4)(C(6)H(9)O(8)) [ammonium D-saccharate, NH(4)-SAC], has been synthesized, and its crystal structure solved by single-crystal X-ray diffraction methods. NH(4)-SAC crystallizes in the monoclinic space group P2(1) (#4) with cell parameters a = 4.8350(4) Angstroms, b = 11.0477(8) Angstroms, c = 16.7268(12) Angstroms, beta = 90.973(1) degrees, V = 894.34(12) Angstroms(3), Z = 3. The structure was refined by full-matrix least-squares on F(2) yielding final R-values (all data) R1 = 0.0353 and R(w)2 = 0.0870. The structure consists of alternating (NH(4))(+) and (C(6)H(11)O(6))(-) layers parallel to the bc plane. An extended network of N-H...O(SAC) and O(SAC)-H...O(SAC) hydrogen bonds provide the 3-D connectivity. The aqueous solubility (S(w)) has been shown to be pH independent at ambient conditions within the range 4.5 < pH < 10 with S(w) = 2.19 M/L, whose value is about a factor of two lower than that of the ammonium isosaccharate analogue.


Subject(s)
Glucaric Acid/analogs & derivatives , Glucaric Acid/chemistry , Crystallography, X-Ray , Drug Stability , Hot Temperature , Hydrogen Bonding , Solubility , Water
12.
Obstet Gynecol ; 105(2): 246-54, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15684147

ABSTRACT

OBJECTIVE: To identify important clinical correlates of stroke in patients with preeclampsia and eclampsia. METHODS: The case histories of 28 patients who sustained a stroke in association with severe preeclampsia and eclampsia were scrutinized with particular attention to blood pressures. RESULTS: Stroke occurred antepartum in 12 patients, postpartum in 16. Stroke was classified as hemorrhagic-arterial in 25 of 27 patients (92.6%) and thrombotic-arterial in 2 others. Multiple sites were involved in 37% without distinct pattern. In the 24 patients being treated immediately before stroke, systolic pressure was 160 mm Hg or greater in 23 (95.8%) and more than 155 mm Hg in 100%. In contrast, only 3 of 24 patients (12.5%) exhibited prestroke diastolic pressures of 110 mm Hg or greater, only 5 of 28 reached 105 mm Hg, and only 6 (25%) exceeded a mean arterial pressure of 130 mm Hg before stroke. Only 3 patients received prestroke antihypertensives. Twelve patients sustained a stroke while receiving magnesium sulfate infusion; 8 had eclampsia. Although all blood pressure means after stroke were significantly higher than prestroke, only 5 patients exhibited more than 110 mm Hg diastolic pressures. In 18 of 28 patients, hemolysis, elevated liver enzymes, low platelets syndrome did not significantly alter blood pressures compared with non-hemolysis, elevated liver enzymes, low platelets. Mean systolic and diastolic changes from pregnancy baseline to prestroke values were 64.4 and 30.6 mm Hg, respectively. Maternal mortality was 53.6%; only 3 patients escaped permanent significant morbidity. CONCLUSION: In contrast to severe systolic hypertension, severe diastolic hypertension does not develop before stroke in most patients with severe preeclampsia and eclampsia. A paradigm shift is needed toward considering antihypertensive therapy for severely preeclamptic and eclamptic patients when systolic blood pressure reaches or exceeds 155-160 mm Hg. LEVEL OF EVIDENCE: III.


Subject(s)
Eclampsia/epidemiology , HELLP Syndrome/epidemiology , Hypertension/epidemiology , Pre-Eclampsia/epidemiology , Pregnancy Outcome , Stroke/epidemiology , Adolescent , Adult , Age Distribution , Blood Pressure Determination , Comorbidity , Eclampsia/diagnosis , Female , HELLP Syndrome/diagnosis , Humans , Hypertension/diagnosis , Incidence , Pre-Eclampsia/diagnosis , Pregnancy , Prenatal Diagnosis , Registries , Retrospective Studies , Risk Assessment , Stroke/diagnosis , Systole/physiology
13.
Carbohydr Res ; 339(17): 2811-6, 2004 Dec 06.
Article in English | MEDLINE | ID: mdl-15542090

ABSTRACT

Ammonium isosaccharate, C6H15NO6.H2O (NH4-ISA), has been synthesized and its crystal structure solved by single-crystal X-ray diffraction methods. NH4-ISA crystallizes in the monoclinic space group P2(1) (#4) with cell parameters a=8.6470(12)A, b=5.0207(7)A, c=9.8193(14)A, beta=91.643(3) degrees , V=426.12(10)A3, Z=2. The structure was refined by full-matrix least-squares on F2 yielding final R-values (all data) R1=0.0485 and Rw2=0.1104. The structure consists of alternating (NH4)+ and (C6H11O6)- layers parallel to the ab plane. An extended network of O-H...O intermolecular (ISA)...(ISA) hydrogen bonds links the (ISA)- anions within the ab plane, while the 3-D connectivity along the c-axis is provided only by (ISA-)...(NH4+)...(ISA-) hydrogen bonds. The aqueous solubility (Si, [ML(-1)]) of NH4- and Na-ISA has been shown to be pH independent at ambient conditions within the range 4.5

Subject(s)
Quaternary Ammonium Compounds/chemistry , Sugar Acids/chemistry , Crystallization , Crystallography, X-Ray , Hydrogen Bonding , Hydrogen-Ion Concentration , Models, Molecular , Molecular Structure , Solubility , Temperature , Water/chemistry
14.
Carbohydr Res ; 339(4): 801-5, 2004 Mar 15.
Article in English | MEDLINE | ID: mdl-14980822

ABSTRACT

Sodium isosaccharate, NaC(6)H(11)O(6).H(2)O (Na-ISA), has been synthesized, and its crystal structure solved by single-crystal X-ray diffraction methods. Na-ISA crystallizes in the monoclinic space group P2(1) (#4) with cell parameters a = 9.2267(11) A, b = 5.0765(6) A, c = 9.7435(11) A, beta = 103.304(2) degrees, V = 444.13(9) A(3), Z = 2. The structure was refined by full-matrix least-squares on F2 yielding final R-values (all data) R1 = 0.0361 and Rw2 = 0.0935. The structure of Na-ISA consists of (C(6)H(11)O(6))(-) anions arranged in layers parallel to the bc plane. An extended network of O-H...O hydrogen bonds links the (ISA)(-) anions and the crystal water molecules. Each sodium atom is coordinated by four oxygen atoms belonging to four different (ISA)(-) anions and by one water molecule. The resulting NaO(5) polyhedra are linked by sharing common corners in zig-zag chains running parallel to the b-axis.


Subject(s)
Sugar Acids/chemistry , Carbohydrate Conformation , Crystallography, X-Ray , Hydrogen Bonding , Models, Molecular
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