Additive Manufacturing Post-Processing Treatments, a Review with Emphasis on Mechanical Characteristics.

Additive manufacturing (AM) comes in various types of technologies and comparing it with traditional fabrication methods provides the possibility of producing complex geometric parts directly from Computer-Aided Designs (CAD). Despite answering challenges such as poor workability and the need for tooling, the anisotropy of AM constructions is the most serious issue encountered by their application in industry. In order to enhance the microstructure and functional behavior of additively fabricated samples, post-processing treatments have gained extensive attention. The aim of this research is to provide critical, comprehensive, and objective methods, parameters and results' synthesis for post-processing treatments applied to AM builds obtained by 3D printing technologies. Different conditions for post-processing treatments adapted to AM processes were explored in this review, and demonstrated efficiency and quality enhancement of parts. Therefore, the collected results show that mechanical characteristics (stress state, bending stress, impact strength, hardness, fatigue) have undergone significant improvements for 3D composite polymers, copper-enhanced and aluminum-enhanced polymers, shape memory alloys, high-entropy alloys, and stainless steels. However, for obtaining a better mechanical performance, the research papers analyzed revealed the crucial role of related physical characteristics: crystallinity, viscosity, processability, dynamic stability, reactivity, heat deflection temperature, and microstructural structure.

Advancements in Fiber-Reinforced Polymer Composites: A Comprehensive Analysis.

Composites made from fiber-reinforced polymers (FRPs) are a crucial and highly adaptable category of materials widely utilized in numerous fields. Their flexibility and the range of criteria for classification enable the creation of tailored solutions to address distinct requirements in sectors such as civil engineering, aerospace, automotive, and marine, among others. The distinguishing characteristics of FRP composites include the type of reinforcing fiber used, the composition of the matrix material, the employed manufacturing process, the orientation of the fibers, and the specific end-use application. These classification variables offer engineers a versatile structure to determine and select the most appropriate materials and production techniques for their specific needs. Furthermore, the present study aims to reunite the criteria of classification for FRPs and specific manufacturing technologies of FRPs, such as conventional ones (matched die molding, contact molding), automated ones (filament winding, tape lay-up, and fiber placement), and advanced ones (electrospinning and additive manufacturing),with the chronological development of FRPs, insights on material characteristics, and comprehensive design guidelines based on their behavior in different environments of use.

Management of endometrial modifications in perimenopausal women.

Perimenopause has a variable length and time of onset and is characterized by its variability in hormonal levels. The histological changes in the perimenopausal endometrium may be represented by nonproliferative or proliferative benign or malignant lesions. A commonly encountered manifestation of endometrium lesions during menopausal transition is the abnormal uterine bleeding (AUB). The clinical management of AUB must follow a standardized classification system for optimal results. The medical and surgical treatment must be adapted according to age, risk factors, symptoms, and cycle irregularities. Use of alternative therapies and proper diet may result in improved long-term outcomes.

Pro-inflammatory cytokines for evaluation of inflammatory status in endometriosis.

THE AIM OF THE STUDY: The aim of the study was to investigate the serum pro-inflammatory cytokine profile in patients with diagnosed endometriosis. MATERIAL AND METHODS: The study included 160 women, who were divided in two study groups (Group I - endometriosis; Group 2 - healthy). We evaluated the serum levels of interleukin (IL)-1ß, IL-5, IL-6, IL-7, and IL-12, and of tumour necrosis factor α (TNF-α) with the use of Human Multiplex Cytokine Panels. RESULTS: The serum level of IL-1ß, IL-6, and TNF-α is significantly higher in women with endometriosis compared to women free of disease, from the control group (mean 10.777, 183.027, and 131.326, respectively, compared to 3.039, 70.043, and 75.285, respectively; p = 0.002, p < 0.001, and p = 0.015, respectively). No significant differences in the serum levels of IL-5 and IL-12 were observed between the studied groups, and IL-7 had a very low detection rate. CONCLUSIONS: Women with endometriosis have elevated levels of key pro-inflammatory cytokines, i.e. IL-1ß, IL-6, and TNF-α. At the same time, IL-1ß and IL-6 could be used as predictors for endometriosis.

Maternal smoking during pregnancy and birth outcomes in a sample of Romanian women.

Smoking during pregnancy is causally associated with reduced birth weight and is strongly related to preterm birth. Smoking cessation in early pregnancy seems to reduce these risks, although the research evidence is limited. In a sample of Romanian women, differences in birth outcomes were assessed between non-smokers and women who continued to smoke during pregnancy and non-smokers and women who stopped smok- ing when they found out about the pregnancy. Pregnant women were recruited in two urban clinics (N= 474). A baseline questionnaire collected information on their smoking status, depressive symptoms, stress, demographics, and other characteristics at recruitment. The women reported the newborn weight and birth term by phone in the first weeks following birth. Descriptive statistics and multivariate regressions were used to ana- lyze the relationship between smoking status during pregnancy and birth outcomes. Over 61% (N = 290) women were non-smokers, 15% (N= 72) smoked during pregnancy, and 24% (N= 112) quit smoking when they found out about the pregnancy. Compared to non-smokers, continuous smokers delivered babies 165 grams lighter (95% CI -313, -17). Women who stopped smoking when they ascertained the pregnancy had higher odds of delivering a newborn who was small for gestational age compared to non-smokers (OR= 2.16, 95% CI 1.05, 4.43). Elevated maternal stress was associated with reduced birth weight (-113 grams, 95% CI -213, -11), and higher odds of a preterm birth (OR=2.8, 95% CI 1.17, 6.76). In a predominantly urban sample of Romanian women, continuous maternal smoking during pregnancy was a risk factor for restricted foetal growth. Smoking cessation when the pregnancy was ascertained did not seem to reduce this risk. Smoking prevention efforts should therefore begin before pregnancy and should integrate psychological components, addressing maternal stress in particular.

Ovarian pregnancy associated with pelvic adhesions.

Ovarian pregnancy is a rare entity. Making a definitive preoperative or even intraoperative diagnosis of ovarian pregnancy is difficult and the diagnosis is usually established by the pathologist. Rupture in the first trimester is the usual rule in ovarian ectopy. Thus, it continues to challenge practicing clinicians. The literature shows an association between intrauterine device usage and ovarian gestation. We present a case of ovarian pregnancy in a secundipara complaining of abdominal pain that also has pelvic adhesions. This case meets the four criteria of Spiegelberg and is interesting because of its rarity and association with adhesions, which makes diagnosis more difficult.

Evaluation of serum ß-hCG and PAPP-A levels in pregnant women at risk of developing preeclampsia.

BACKGROUND AND AIM: Preeclampsia remains a major problem of modern obstetrics with insufficiently elucidated etiology; early detection would diminish maternal and fetal mortality and morbidity. The aim of this study was to determine the serum values of ß-hCG in the first and second trimesters of pregnancy and PAPP-A values in the first trimester of pregnancy in pregnant women with risk factors for preeclampsia, in order to evaluate their relevance in the prediction of this disorder. MATERIAL AND METHODS: We performed a prospective longitudinal study on 120 pregnant women divided into two groups according to the evolution of pregnancy: group I - 26 pregnant women who developed preeclampsia and group II - 94 pregnant women who did not develop preeclampsia and had a physiological evolution of pregnancy. RESULTS: Our results indicate the association between high ß-hCG levels in the first and second trimesters of pregnancy and the development of PE, ß-hCG having the highest predictive power in the second trimester. We also obtained a positive association between low serum levels in PAPP-A in the first trimester and onset of PE. The predictive power of conjugated ß-hCG and PAPP-A values in the first trimester of pregnancy was better that any other marker analyzed separately. CONCLUSIONS: Increased ß-hCG levels in the first and second trimesters of pregnancy and low PAPP-A levels in the second trimester of pregnancy are associated with a higher risk for PE, the study providing only a modest efficiency of the prediction capacity.

Predictors of limph node metastasis in endometrial cancer.

INTRODUCTION: Endometrial cancer is the most common gynecologic malignancy in developed countries. The adequate surgical staging proposed by FIGO (International Federation for Gynaecology and Obstetrics) advocates lymphadenectomy; however, it does not establish the indications, the type and the extent of lymphadenectomy, thus generating multiple controversies. METHODS: Retrospective, analytical study of patients treated surgically for endometrial adenocarcinoma in the Oncological Institute "Prof. Dr. Ion Chiricuta" Cluj-Napoca (IOCN) between January 2008 and December 2012 - 709 cases eligible for the study. RESULTS: 206 pelvic and/or paraaortic lymphadenectomies were performed, the average number of excised lymph nodes being 15.6. Overall in 4.4% of patients the lymph nodes were affected by metastases. The presence of each risk factor analysed was statistically significantly associated with lymph node metastasis (p<0.05). Age above 55 years was statistically significantly associated (p<0.05) with the presence of negative prognostic factors in the study. CONCLUSIONS: The analysed histopathological and clinical prognostic factors were statistically significantly associated with lymphatic dissemination in endometrial cancer. We recommend treating endometrial cancer in tertiary centres by surgeons or gynaecologists-oncologists with experience in extensive peritoneal and retroperitoneal surgery.

Left ventricular noncompaction and aneurysm revealed by left ventriculography.

Left ventriculography (LVG) is sometimes not performed during cardiac catheterization when results of prior noninvasive tests are available. We present a rare case of left ventricular noncompaction coexisting with left ventricular aneurysm diagnosed during cardiac catheterization. LVG could provide additional information in patients with nonobstructive coronary artery disease and decreased ejection fraction on noninvasive tests.

Implications of maternal systemic oxidative stress in normal pregnancy and in pregnancy complicated by preeclampsia.

OBJECTIVES: To evaluate the intensity of oxidative stress in normal pregnancy and in pregnancy complicated by preeclampsia. To investigate a possible correlation between the intensity of oxidative stress, severity of preeclampsia and the fetal status at birth. MATERIALS AND METHODS: A retrospective transversal study was performed in three groups of 80 patients each: Group I--preeclampsia; Group II--normal pregnancy; Group III--control (non-pregnant patients). Degradation products of reactive oxygen species (lipid peroxides and protein carbonyls) and some antioxidants (hydrogen donor capacity and ceruloplasmin) were determined in the serum of patients. The data obtained were processed by descriptive and comparative statistical methods. RESULTS: A moderate level of oxidative stress was found in normal pregnancy. We found statistically significant differences between the control group and the normal pregnancy group (p < 0.000). In preeclampsia, oxidative stress increases. Statistically significant differences were found in the evaluated parameters between the normal pregnancy group and the preeclampsia group (p < 0.000). There were no correlations between the intensity of oxidative stress, severity of preeclampsia and the fetal status at birth in the group with preeclampsia. CONCLUSION: Oxidative stress in preeclampsia is the result of the increase in reactive oxygen species and of the decrease in antioxidants.

Effect of melatonin on intra-abdominal fat in correlation with endometrial proliferation in ovariectomized rats.

BACKGROUND AND AIM: In the context of endometrial cancer, visceral obesity as a risk factor is associated with a chronic inflammatory process, confirmed by an increase in inflammatory marker levels. Blood melatonin levels are inversely correlated with the tumor proliferation index in patients with endometrial cancer. The aim of this study was the experimental exploration of the effects of melatonin and melatonin associated with estrogen on metabolic changes, intraperitoneal fat and endometrial proliferation in female rats with surgically induced menopause. MATERIAL AND METHODS: The current study included 50 rats. At 14 days post-ovariectomy, the animals were exposed to estrogen replacement treatment and combined treatment of estrogen and melatonin. The duration of the administered treatment, with products and doses recommended for veterinary use, was 12 consecutive weeks. The endometrial thickness was ultrasonographically assessed. For statistical analysis, Student's t-test or the Mann-Whitney test, in the case of the non-parametric distribution, were used. RESULTS: The groups receiving estrogen associated with melatonin had a lower body weight (222.20±3.34 g vs. 232.50±3.44 g, p<0.001), less intra-retroperitoneal fat (4.97±0.94 g vs. 7.93±0.64 g, p<0.001), and lower endometrial proliferation (0.122±0.010 vs. 0.133±0.009 p=0.04), compared to the control group. CONCLUSION: The addition of melatonin to estrogen replacement treatment is associated with a decrease in endometrial proliferation and prevents the appearance of cellular atypia. The presented results suggest that melatonin supplementation may play an important role in the prophylaxis of endometrial cancer in menopause.

Applications of Doppler ultrasound during labor.

The information provided by Doppler ultrasound examination during labor permits the understanding of the mechanisms regarding the physiology and pathophysiology of feto-placental exchange and the fetal adaptive systems. There are certain technical difficulties related to intrapartum Doppler ultrasound examination. The investigated sites are the uterine arteries, umbilical arteries, fetal circulation. In diastole, when intrauterine pressure exceeds maternal diastolic pressure, the perfusion pressure of the uterine artery blood flow is no longer present. A progressive decrease in the diastolic component is seen along with an increase in intrauterine pressure from 10 to 60 mmHg. During premature birth or preeclampsia, there are particular changes in the uterine blood flow. A remarkable stability of the umbilical resistance index is found during labor, which shows the permanent presence of feto-placental exchange. Certain correlations can be established between fetal heart rate changes in labor and Doppler ultrasound aspects at the level of umbilical arteries. Doppler examination confirms the concept of reduced cerebral blood flow by the compression of the fetal skull as a cause of decelerations occurring during labor. The decision regarding the extraction of the fetus can only be made by correlating the results of Doppler ultrasound with the other paraclinical methods for the monitoring of the intrapartum fetal status.

HELLP syndrome - a multisystemic disorder.

HELLP syndrome is a multisystemic disorder with an incidence of 0.17-0.85% of all pregnancies. Its etiopathogenesis is not completely understood. The most widely accepted hypotheses are: a change in the immune feto-maternal balance, platelet aggregation, endothelial dysfunction, arterial hypertension and an inborn error of the fatty acid oxidative metabolism. Hepatic involvement occurs by intravascular fibrin deposition and hypovolemia. Materno-fetal complications cause a 6.7-70% perinatal mortality rate and a 1-24% maternal mortality rate. The recognition of HELLP syndrome and the rapid initiation of therapy are required for the improvement of materno-fetal prognosis.