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Seminal oxidative stress (OS) is a major contributing factor to male infertility. Semen analysis cannot identify reactive oxygen species (ROS), which can be measured using a chemiluminescence assay. Measurement of redox potential provides a more comprehensive assessment of OS, although the test has yet to be fully validated. This study aimed to validate the MiOXsys analyser for measuring static oxidation–reduction potential (sORP). Results demonstrated that duplicate measurements must be taken, sensors must be batch tested, and sockets should be regularly changed to avoid inconsistency in measurement. Measurement of sORP using MiOXsys exhibited good reproducibility across different operators (p = 0.469), analysers (p = 0.963) and days (p = 0.942). It is not affected by mechanical agitation (p = 0.522) or snap freezing and thawing (p = 0.823). The stability of sORP over time requires further verification, particularly in samples with high initial sORP. Measurement is temperature sensitive between 2 and 37°C, significantly increasing with increasing temperature (p = 0.0004). MiOXsys is a more stable assay for assessing OS than chemiluminescence methods and permits greater flexibility for sample handling. MiOXsys could be implemented to complement semen analysis as part of routine diagnostic testing for male infertility and may be useful in identifying contributing factors to idiopathic infertility.  相似文献   
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Patients with chronic myelofibrosis often suffer from osteosclerosis, which is associated with bone pain and may lead to bone marrow failure. The pathogenesis of myelofibrosis is linked to aberrant megakaryocyte development and function. Null and loss-of-function mutations in MPIG6B, which codes for the inhibitory heparan sulfate receptor G6b-B, result in severe macrothrombocytopenia, large megakaryocyte clusters, and focal primary myelofibrosis in mice and humans. We investigated the development of osteosclerosis in Mpig6b null (Mpig6b−/−) mice. Although male and female Mpig6b−/− mice presented with elevated bone marrow megakaryocyte number and macrothrombocytopenia, female Mpig6b−/− mice developed progressive splenomegaly starting at 8 weeks of age. Micro–computed tomography (μCT) of femurs showed that female Mpig6b−/− mice had increased cortical thickness and reduced bone marrow area starting at 8 weeks of age and developed occlusion of the medullary cavity by trabeculae by 16 weeks of age. In contrast, male Mpig6b−/− mice developed only a small number of trabeculae in the medullary cavity at the proximal diaphysis and demonstrated a temporary decrease in bone volume fraction and trabecular thickness at 16 weeks. Ovariectomy of 10-week-old female Mpig6b−/− mice prevented the development of medullary cavity osteosclerosis, whereas orchiectomy of male Mpig6b−/− mice did not exacerbate their disease. Importantly, ovariectomized female Mpig6b−/− mice also demonstrated improvement in spleen weight compared to sham-operated Mpig6b−/− mice, establishing estrogen as a contributing factor to the severity of the megakaryocyte-driven osteosclerosis. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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BackgroundSelection of the optimal treatment modality for primary liver cancers remains complex, balancing patient condition, liver function, and extent of disease. In individuals with preserved liver function, liver resection remains the primary approach for treatment with curative intent but may be associated with significant mortality. The purpose of this study was to establish a simple scoring system based on Model for End-stage Liver Disease (MELD) and extent of resection to guide risk assessment for liver resections.MethodsThe 2005–2015 NSQIP database was queried for patients undergoing liver resection for primary liver malignancy. We first developed a model that incorporated the extent of resection (1 point for major hepatectomy) and a MELD-Na score category of low (MELD-Na =6, 1 point), medium (MELD-Na =7–10, 2 points) or high (MELD-Na >10, 3 points) with a score range of 1–4, called the Hepatic Resection Risk Score (HeRS). We tested the predictive value of this model on the dataset using logistic regression. We next developed an optimal multivariable model using backwards sequential selection of variables under logistic regression. We performed K-fold cross validation on both models. Receiver operating characteristics were plotted and the optimal sensitivity and specificity for each model were calculated to obtain positive and negative predictive values.ResultsA total of 4,510 patients were included. HeRS was associated with increased odds of 30-day mortality [HeRS =2: OR =3.23 (1.16–8.99), P=0.025; HeRS =3: OR =6.54 (2.39–17.90), P<0.001; HeRS =4: OR =13.69 (4.90–38.22), P<0.001]. The AUC for this model was 0.66. The AUC for the optimal multivariable model was higher at 0.76. Under K-fold cross validation, the positive predictive value (PPV) and negative predictive value (NPV) of these two models were similar at PPV =6.4% and NPV =97.7% for the HeRS only model and PPV =8.4% and NPV =98.1% for the optimal multivariable model.ConclusionsThe HeRS offers a simple heuristic for estimating 30-day mortality after resection of primary liver malignancy. More complicated models offer better performance but at the expense of being more difficult to integrate into clinical practice.  相似文献   
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Thirty-six previously untreated cases of head and neck cancer were given a combined therapy of irradiation and intra-arterial, one-shot injection of Cisplatin. As a result, the primary lesions in 35 cases were seen to achieve a 66% complete remission (CR) and a 100% overall response (OR). The lymph metastases in twenty-one cases with positive node achieved a 62% CR and a 100% OR. Good, local control of supraglottic and hypopharyngeal cancers were found to be an advantageous factor considered from the standpoint of the "quality of life". The cumulative survival rate, using Kaplan-Meier's method, was 82% for the first year, and 62% for the second year. No severe side effects were observed.  相似文献   
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Hair shaft disorders are characterized by congenital or acquired abnormalities of the hair shaft. The objective was to review the literature regarding the prognosis and treatment options of hair shaft disorders. We used keywords in the search engines PubMed and Medline to identify all publications in the English language related to the prognosis and management of hair shaft disorders. Data were extracted from 96 articles that met search criteria. Findings were limited to case reports and small case series, as no studies were found. Disorders that improve in childhood include pili torti, trichorrhexis invaginata, wooly hair, and pili trianguli et canaliculi. Others, such as trichorrhexis nodosa, monilethrix, pili annulati, and pili bifurcati improve with minoxidil. Oral retinoids have improved hair abnormalities in trichorrhexis invaginata and monilethrix. There is no specific treatment for congenital hair shaft abnormalities. Gentle hair care is the mainstay of care for hair shaft disorders associated with fragility. Practices for gentle care include no brushing, backcombing, chemical products, tight braids, heat exposure, or mechanical grooming. Any inherited or congenital disorder requires genetic counseling as part of management.  相似文献   
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Hair shaft disorders are characterized by congenital or acquired abnormalities of the hair shaft. The objective of this study was to review the literature regarding the prognosis and treatment options for hair shaft disorders. We used keywords in the search engines PubMed and Medline to identify all publications in English related to the prognosis and management of hair shaft disorders. Data were extracted from 96 articles that met search criteria. Findings were limited to case reports and small case series, as no studies were found. Disorders that improve in childhood include pili torti, trichorrhexis invaginata, woolly hair, and pili trianguli et canaliculi. Others, such as trichorrhexis nodosa, monilethrix, pili annulati, and pili bifurcati, improve with minoxidil. Oral retinoids have been found to improve hair abnormalities in trichorrhexis invaginata and monilethrix. There is no specific treatment for congenital hair shaft abnormalities. Gentle hair care is the mainstay of care for hair shaft disorders associated with fragility. Practices for gentle care include no brushing, backcombing, chemical products, tight braids, heat exposure, or mechanical grooming. Furthermore, any inherited or congenital disorder requires genetic counseling as part of management.  相似文献   
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Converging evidence from clinical, preclinical, neuroimaging, and genetic research implicates dopamine neurotransmission in the pathophysiology of attention deficit hyperactivity disorder (ADHD). The in vivo neuroreceptor imaging evidence also suggests alterations in the dopamine system in ADHD; however, the nature and behavioral significance of those have not yet been established. Here, we investigated striatal dopaminergic function in ADHD using [11C]raclopride PET with a d-amphetamine challenge. We also examined the relationship of striatal dopamine responses to ADHD symptoms and neurocognitive function. A total of 15 treatment-free, noncomorbid adult males with ADHD (age: 29.87±8.65) and 18 healthy male controls (age: 25.44±6.77) underwent two PET scans: one following a lactose placebo and the other following d-amphetamine (0.3 mg/kg, p.o.), administered double blind and in random order counterbalanced across groups. In a separate session without a drug, participants performed a battery of neurocognitive tests. Relative to the healthy controls, the ADHD patients, as a group, showed greater d-amphetamine-induced decreases in striatal [11C]raclopride binding and performed more poorly on measures of response inhibition. Across groups, a greater magnitude of d-amphetamine-induced change in [11C]raclopride binding potential was associated with poorer performance on measures of response inhibition and ADHD symptoms. Our findings suggest an augmented striatal dopaminergic response in treatment-naive ADHD. Though in contrast to results of a previous study, this finding appears consistent with a model proposing exaggerated phasic dopamine release in ADHD. A susceptibility to increased phasic dopamine responsivity may contribute to such characteristics of ADHD as poor inhibition and impulsivity.  相似文献   
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