scholarly journals Former-preterm lambs have persistent alveolar simplification at 2 and 5 months corrected postnatal age

2018 ◽  
Vol 315 (5) ◽  
pp. L816-L833 ◽  
Author(s):  
Mar Janna Dahl ◽  
Sydney Bowen ◽  
Toshio Aoki ◽  
Andrew Rebentisch ◽  
Elaine Dawson ◽  
...  

Preterm birth and mechanical ventilation (MV) frequently lead to bronchopulmonary dysplasia, the histopathological hallmark of which is alveolar simplification. How developmental immaturity and ongoing injury, repair, and remodeling impact completion of alveolar formation later in life is not known, in part because of lack of suitable animal models. We report a new model, using former-preterm lambs, to test the hypothesis that they will have persistent alveolar simplification later in life. Moderately preterm lambs (~85% gestation) were supported by MV for ~6 days before being transitioned from all respiratory support to become former-preterm lambs. Results are compared with term control lambs that were not ventilated, and between males (M) and females (F). Alveolar simplification was quantified morphometrically and stereologically at 2 mo (4 M, 4 F) or 5 mo (4 M, 6 F) corrected postnatal age (cPNA) compared with unventilated, age-matched term control lambs (4 M, 4 F per control group). These postnatal ages in sheep are equivalent to human postnatal ages of 1–2 yr and ~6 yr, respectively. Multivariable linear regression results showed that former-preterm lambs at 2 or 5 mo cPNA had significantly thicker distal airspace walls ( P < 0.001 and P < 0.009, respectively), lower volume density of secondary septa ( P < 0.007 and P < 0.001, respectively), and lower radial alveolar count ( P < 0.003 and P < 0.020, respectively) compared with term control lambs. Sex-specific differences were not detected. We conclude that moderate preterm birth and MV for ~6 days impedes completion of alveolarization in former-preterm lambs. This new model provides the opportunity to identify underlying pathogenic mechanisms that may reveal treatment approaches.

Author(s):  
D.C. Dominguez ◽  
J.T. Ellzey

Peroxisomes which participate in 1ipid metabolism have been shown to be altered in several metabolic disorders and toxic conditions. In alcoholic liver disease, the single lesion most frequently found is lipid accumu1ation in hepatocytes. However, the mechanisms for this 1ipid accumu1ation are not clear. The occurrence of modifications of liver peroxisomes due to excess alcohol consumption has not been subjected to a controlled study. We utilized a combination of cytochemica1 and morphometrictechniques to study the size and number of liver peroxisomes in rats fed an alcohol-supplemented diet compared to those of matched-paired control animals.Male Sprague-Daw1ey rats (400-500 g) received a liquid diet. The experimental group (N = 5/group) was fed a diet containing 30% ethanol-derived calories (EDC) and the control group was fed an isocaloric diet to 30% EDC. A pair feeding procedure was employed to control for caloric intake. Small pieces of liver randomly selected, were fixed in 2.3% -glutaraldehyde in 0.1 M sodium cacodylate buffer, pH 7.2, incubated in a DAB medium and postfixed with. 2% aqueous osmium tetroxide. EM photographs were taken from sections of 3 tissue blocks from each sample (7,200X) with a Zeiss EM10-A (60 kV). With the use of a point counting method and a digital planimeter the volume density (Vv) and numerical density (Nv) were determined.


Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 466
Author(s):  
Weiwei Du ◽  
Yarui Xi ◽  
Kiichi Harada ◽  
Yumei Zhang ◽  
Keiko Nagashima ◽  
...  

Research shows that the intensity impact factors of wood, such as late timber ratio, volume density and the intensity of itself, correlate with the width of wood annual rings. Therefore, extracting wood annual ring information from wood images is helpful for evaluating wood quality. During the past few years, many researchers have conducted defect detection by studying the information of wood images. However, there are few in-depth studies on the statistics and calculation of wood annual ring information. This study proposes a new model combining the Total Variation (TV) algorithm and the improved Hough transform to accurately measure the wood annual ring information. The TV algorithm is used to suppress image noise, and the Hough transform is for detecting the center of the wood image. Moreover, the edges of wood annual rings are extracted, and the statistical ring information is calculated. The experimental results show that the new model has good denoising capability, clearly extract the edges of wood annual rings and calculate the related parameters from the indoor wood images of the processed logs and the unprocessed low-noise logs.


Author(s):  
Megan R. Sutherland ◽  
Waleed Malik ◽  
Vivian B. Nguyen ◽  
Vivian Tran ◽  
Graeme R. Polglase ◽  
...  

Abstract Preterm birth (delivery <37 weeks of gestation) is associated with impaired glomerular capillary growth in neonates; if this persists, it may be a contributing factor in the increased risk of hypertension and chronic kidney disease in people born preterm. Therefore, in this study, we aimed to determine the long-term impact of preterm birth on renal morphology, in adult sheep. Singleton male sheep were delivered moderately preterm at 132 days (~0.9) of gestation (n = 6) or at term (147 days gestation; n = 6) and euthanised at 14.5 months of age (early adulthood). Stereological methods were used to determine mean renal corpuscle and glomerular volumes, and glomerular capillary length and surface area, in the outer, mid and inner regions of the renal cortex. Glomerulosclerosis and interstitial collagen levels were assessed histologically. By 14.5 months of age, there was no difference between the term and preterm sheep in body or kidney weight. Renal corpuscle volume was significantly larger in the preterm sheep than the term sheep, with the preterm sheep exhibiting enlarged Bowman’s spaces; however, there was no difference in glomerular volume between groups, with no impact of preterm birth on capillary length or surface area per glomerulus. There was also no difference in interstitial collagen levels or glomerulosclerosis index between groups. Findings suggest that moderate preterm birth does not adversely affect glomerular structure in early adulthood. The enlarged Bowman’s space in the renal corpuscles of the preterm sheep kidneys, however, is of concern and merits further research into its cause and functional consequences.


2014 ◽  
Vol 99 (Suppl 1) ◽  
pp. A6.3-A7
Author(s):  
S Johnson ◽  
ES Draper ◽  
TA Evans ◽  
DJ Field ◽  
A Guy ◽  
...  

2018 ◽  
Vol 55 (suppl 1) ◽  
pp. 25-29 ◽  
Author(s):  
Roberto Oliveira DANTAS ◽  
Rachel Aguiar CASSIANI ◽  
Carla Manfredi SANTOS ◽  
Leda Maria Tavares ALVES

ABSTRACT BACKGROUND: Achalasia is a disease that affects esophageal bolus transit due to the absence of esophageal peristaltic contractions and impaired or absent relaxation of the lower esophageal sphincter. OBJECTIVE: The objective of this investigation was: a) to evaluate the dynamics of water ingestion in patients with achalasia, idiopathic or caused by Chagas’ disease; b) to evaluate the influence of sex and age on water ingestion dynamics. METHODS: The investigation was conducted with 79 patients with achalasia (27 idiopathic and 52 Chagas’ disease) and 91 healthy volunteers, all evaluated by the water-drinking test. The individuals drank, in triplicate, 50 mL of water without interruption. The time and the number of swallows for this task were counted. We also measured: (a) inter-swallow interval - the time to complete the task, divided by the number of swallows during the task; (b) swallowing rate - volume drunk divided by the time; (c) volume per swallow - volume drunk divided by the number of swallows. RESULTS: Patients with achalasia took longer to ingest all the volume (mean 12.2 seconds) than healthy controls (mean 5.4 seconds), had greater number of swallows, longer interval between swallows, lower swallowing rate (5.2 mL/s vs 10.9 mL/s in controls) and lower volume per swallow (9.1 mL vs 14.4 mL in controls, P<0.01). Among healthy volunteers, women had a shorter interval between swallows and lower volume per swallow compared with men, and in the achalasia group, women had a longer interval between swallows and lower ingestion rate. No difference in the drinking test results was found between younger and older subjects in achalasia or control group. Also, no differences were observed between patients with Chagas’ disease and those with idiopathic achalasia, or between patients with increased and normal esophageal diameter. CONCLUSION: Patients with achalasia have difficulty in ingesting water, taking a longer time to complete the task, which is influenced by sex but not by age or severity of the disease.


2017 ◽  
Vol 23 (6) ◽  
pp. 441-445
Author(s):  
Ledimar Brianezi ◽  
Mara Rubia Marques ◽  
Clever Gomes Cardoso ◽  
Maria Luiza de Jesus Miranda ◽  
Fernando Luiz Affonso Fonseca ◽  
...  

ABSTRACT Introduction: The emergence of coronary heart disease increases with menopause, physical inactivity and with dyslipidemia. It is known that physical training promotes the improvement of cardiovascular functions. Objective: The purpose of this study was to investigate the effects of aerobic physical training on the left ventricle in female LDL knockout ovariectomized mice. Methods: Thirty animals were divided into 6 groups (n=5), namely, sedentary non-ovariectomized control; sedentary ovariectomized control; trained ovariectomized control; sedentary non-ovariectomized; sedentary ovariectomized; and trained ovariectomized. We analyzed the mean nuclear volume parameters, the cross sectional area of the myocytes, the apparent density of the capillaries, interstitium, myocytes and collagen fibers. Results: The results show that for the density of the number of nuclei, the physical activity decreased to values close to the ovariectomized control group. Regarding the mean nuclear volume and the average area of myocytes, training and ovariectomy promoted the elevation of these values but hypercholesterolemia was lower. the volume density of myocytes, hypercholesterolemia showed an increase of these values as well as the training. There was no change in the volumetric density of the capillaries and the density of collagen fibers. The training caused the decrease in the density of the interstitial volume, and the hypercholesterolemia changed to a smaller one than the control group. Conclusion: We concluded that the moderate aerobic activity or the training time used in our study were not sufficient to generate significant alterations in the hypercholesterolemic group.


2019 ◽  
Author(s):  
Eline Skirnisdottir Vik ◽  
Roy Miodini Nilsen ◽  
Vigdis Aasheim ◽  
Rhonda Small ◽  
Dag Moster ◽  
...  

Abstract Background: This study compares subsequent birth outcomes in migrant women who had already had a child before arriving in Norway with those in migrant women whose first birth occurred in Norway. The aim of this study was to investigate the associations between country of first birth and adverse neonatal outcomes (very preterm birth, moderately preterm birth, post-term birth, small for gestational age, large for gestational age, low Apgar score, stillbirth and neonatal death) in parous migrant and Norwegian-born women. Methods: National population-based study including second and subsequent singleton births in Norway from 1990-2016. Data were retrieved from the Medical Birth Registry of Norway and Statistics Norway. Neonatal outcomes were compared between births to: 1) migrant women with a first birth before immigration to Norway (n=30,062) versus those with a first birth after immigration (n=66,006), and 2) Norwegian-born women with a first birth outside Norway (n=6,205) versus those with a first birth in Norway (n=514,799). Associations were estimated as crude and adjusted odds ratios (aORs) with 95% confidence intervals (CIs) using multiple logistic regression. Results: Migrant women with a first birth before immigrating to Norway had increased odds of adverse outcomes in subsequent births relative to those with a first birth after immigration: very preterm birth (22-31 gestational weeks (gwks); aOR=1.27; CI 1.09-1.48), moderately preterm birth (32-36 gwks; aOR=1.10; CI 1.02-1.18), post-term birth (≥42 gwks; aOR=1.19; CI 1.11-1.27), low Apgar score (<7 at 5 minutes; aOR=1.27; CI 1.16-1.39) and stillbirth (aOR=1.29; CI 1.05-1.58). Similar results were found in the sample of births to Norwegian-born women. Conclusions: The increased odds of adverse neonatal outcomes for migrant and Norwegian-born women who had their first births outside Norway should serve as a reminder of the importance of taking a careful obstetric history in these parous women to ensure appropriate care for their subsequent pregnancies and births in Norway. Keywords: immigration, parous women, neonatal outcomes, obstetric history, predictor


2021 ◽  
Author(s):  
Brendan Mulcahy ◽  
Daniel Rolnik ◽  
Alexia Matheson ◽  
Yizhen Liu ◽  
Kirsten Palmer ◽  
...  

Background: Community lockdowns during the COVID-19 pandemic may influence preterm birth rates, but mechanisms are unclear. Methods: We compared neonatal outcomes of preterm infants born to mothers exposed to community lockdowns in 2020 (exposed group) to those born in 2019 (control group). Main outcome studied was composite of significant neonatal morbidity or death. Results: Median gestational age was 35+4 weeks (295 infants, exposed group) vs. 35+0 weeks (347 infants, control group) (p = 0.108). The main outcome occurred in 36/295 (12.2%) infants in exposed group vs. 46/347 (13.3%) in control group (p = 0.69). Continuous positive airway pressure (CPAP) use, jaundice requiring phototherapy, hypoglycaemia requiring treatment, early neonatal white cell and neutrophil counts were significantly reduced in the exposed group. Conclusions: COVID-19 community lockdowns did not alter composite neonatal outcomes in preterm infants, but reduced rates of some common outcomes, and early white cell and neutrophil counts.


2021 ◽  
Vol 23 (3) ◽  
pp. 102-105
Author(s):  
Sheida Shabanian ◽  
Abolfazl Khoshdel ◽  
Majid Dezfuli ◽  
Fatemeh Famouri

Background and aims: Preterm birth can cause high morbidity and mortality in women. Previous evidence has confirmed the association between zinc (Zn) deficiency in x women and some pregnancy complications. This study investigated the association between serum Zn concentration in pregnant women and preterm birth. Methods: This case-control study focused on evaluating 76 pregnant women with preterm birth (case group) and 62 pregnant women with term birth (control group) and was conducted in the obstetrics ward of Hajar hospital, Shahrekord, Iran in 2014. The Zn level was measured by spectrophotometry and data were analyzed by SPSS, version 15. Results: The prevalence of Zn deficiency was 95.6%. The mean of serum Zn concentration was 39.62±11.83 and 59.81±8.8 in the preterm and term delivery groups, respectively (P<0.001). Similarly, the mean of serum Zn concentrations was 43.06±15.6 and 50.46±13.8 in women with and without the rupture of pregnancy membranes, respectively (P=0.01). Based on the findings, the serum Zn concentration was not significantly associated with parity (P=0.634). Conclusion: Although a decrease in the serum Zn concentration could lead to premature rupture of membranes during pregnancy and preterm birth, it could not be considered as the main factor for preterm birth. In addition, Zn deficiency was highly prevalent in pregnant women. Therefore, nutritional interventions should be performed to prevent complications due to the deficiency of micronutrients such as Zn so that to increase health maintenance in mothers and children.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Yen-Lan Chang ◽  
Yi-June Lo ◽  
Sheng-Wei Feng ◽  
Yu-Chih Huang ◽  
Hsin-Yuan Tsai ◽  
...  

The purpose of this study was to investigate whether the use of HLA as an aqueous binder of hydroxyapatite/beta-tricalcium phosphate (HA-βTCP) particles can reduce the amount of bone graft needed and increase ease of handling in clinical situations. In this study, HA/βTCP was loaded in commercially available crosslinking HLA to form a novel HLA/HA-βTCP composite. Six New Zealand White rabbits (3.0–3.6 kg) were used as test subjects. Four 6 mm defects were prepared in the parietal bone. The defects were filled with the HLA/HA-βTCP composite as well as HA-βTCP particle alone. New bone formation was analyzed by micro-CT and histomorphometry. Our results indicated that even when the HA-βTCP particle numbers were reduced, the regenerative effect on bone remained when the HLA existed. The bone volume density (BV/TV ratio) of HLA/HA-βTCP samples was 1.7 times larger than that of the control sample at week 2. The new bone increasing ratio (NBIR) of HLA/HA-βTCP samples was 1.78 times higher than the control group at week 2. In conclusion, HA-βTCP powder with HLA contributed to bone healing in rabbit calvarial bone defects. The addition of HLA to bone grafts not only promoted osteoconduction but also improved handling characteristics in clinical situations.


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