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91.

Purpose

The objective of this case report is to demonstrate that the simple expedient of measuring periodic prolactin levels in patients with MEN1 who have modest hyperprolactinemia and normal pituitary MRI scans is insufficient to monitor for the development of pituitary adenomas.

Methods

Review of relevant literature and chart review.

Results

A 25 year old man with known MEN1 manifested by hyperparathyroidism and a gastrin-producing neuroendocrine tumor was found to have a prolactin [PRL] level of 20.0 ng/mL [1.6–16 ng/mL] but a normal pituitary MRI scan. The impression then was that he had prolactinoma too small to be visualized on the MRI. Over the next 3.5 years his PRL levels remained in this mildly elevated range but he then presented with severe headaches and visual field defects. An MRI showed a 3.1 × 1.7 × 1.9 cm pituitary adenoma with compression of the optic chiasm and invasion of the left cavernous sinus. Surgery revealed a gonadotroph adenoma and he subsequently required gamma knife radiotherapy for residual tumor. Postoperative PRL levels were normal.

Conclusions

Small, intrasellar microadenomas may be associated with elevated PRL levels due to possible direct hormone production [prolactinoma] or possibly to interference with portal vessel blood flow. In monitoring hyperprolactinemic MEN1 patients for the development of pituitary adenomas, measurement of PRL levels is insufficient and periodic MRI scans are necessary at a more frequent interval than every 3–5 years. This may also pertain to patients with “idiopathic” hyperprolactinemia.
  相似文献   
92.

Purpose

Monitoring process conditions during lyophilization is essential to ensuring product quality for lyophilized pharmaceutical products. Residual gas analysis has been applied previously in lyophilization applications for leak detection, determination of endpoint in primary and secondary drying, monitoring sterilization processes, and measuring complex solvents. The purpose of this study is to investigate the temporal evolution of the process gas for various formulations during lyophilization to better understand the relative extraction rates of various molecular compounds over the course of primary drying.

Methods

In this study, residual gas analysis is used to monitor molecular composition of gases in the product chamber during lyophilization of aqueous formulations typical for pharmaceuticals. Residual gas analysis is also used in the determination of the primary drying endpoint and compared to the results obtained using the comparative pressure measurement technique.

Results

The dynamics of solvent vapors, those species dissolved therein, and the ballast gas (the gas supplied to maintain a set-point pressure in the product chamber) are observed throughout the course of lyophilization. In addition to water vapor and nitrogen, the two most abundant gases for all considered aqueous formulations are oxygen and carbon dioxide. In particular, it is observed that the relative concentrations of carbon dioxide and oxygen vary depending on the formulation, an observation which stems from the varying solubility of these species. This result has implications on product shelf life and stability during the lyophilization process.

Conclusions

Chamber process gas composition during lyophilization is quantified for several representative formulations using residual gas analysis. The advantages of the technique lie in its ability to measure the relative concentration of various species during the lyophilization process. This feature gives residual gas analysis utility in a host of applications from endpoint determination to quality assurance. In contrast to other methods, residual gas analysis is able to determine oxygen and water vapor content in the process gas. These compounds have been shown to directly influence product shelf life. With these results, residual gas analysis technique presents a potential new method for real-time lyophilization process control and improved understanding of formulation and processing effects for lyophilized pharmaceutical products.
  相似文献   
93.
Introduction: Despite the significant advances in the pharmacological and interventional management of patients with cardiovascular disease (CVD) over the last decades, cardiovascular mortality remains the leading cause of death. Large randomized clinical trials have investigated the efficacy and safety of different antithrombotic medications in patients with CVD. Although female gender is generally underrepresented in these clinical trials, most analyses clearly indicate that both men and women may accrue therapeutic benefits from antithrombotic management strategies.

Areas covered: This review aims to provide a comprehensive and focused update on gender-related comparative clinical studies of antithrombotic therapies in patients suffering from CVD.

Expert opinion: Current evidence supports the understanding of a similar therapeutic effect between genders with signals of an increased risk of bleeding in women. However, important gaps in evidence exist due to the overall limited percentage of women that have been enrolled in randomized controlled trials. A greater awareness of gender-related issues in antithrombotic therapy should be promoted among physicians and further evidence from large clinical trials looking at the safety and efficacy balance of different antithrombotic strategies in women is warranted.  相似文献   

94.
The purpose of the study was to evaluate the effects of hyperhomocysteinemia (HHC) on vascular-thrombocyte and coagulation hemostasis and the development of coronary artery disease (CAD) in patients with type 2 diabetes mellitus (DM2). DM 2 patients with or without CAD were examined; high incidence of HHC (40.3%) was revealed. The level of homocysteine was significantly higher in DM2 patients with CAD vs. non-CAD subjects. Among patients with DM2 and CAD the level of the amino acid was elevated in 77.1% of cases with a history of myocardial infarction. In patients with DM2, CAD, and HHC, vascular-thrombocyte hemostasis factors were found to be hyperactive, while anticoagulatory ones were suppressed. These changes in the hemostatic system in HHC increase the probability of thrombus formation and CAD progress.  相似文献   
95.
The studies show a dental practitioner as a subject of a wide variety of physical and psychological ailments. It is induced or aggravated by the work specificity and greatly affects the health of dental professionals. Therefore, general health of dentists, especially effect of dental activity on it, is present-day, important and as a matter of fact not well documented subject. The aim of our review is to summarize and ascertain dental practice-related disorders influencing the physical and psychological health of practitioner. Also we would like to highlight the most vulnerable systems of the dental professional and to survey the best methods to overcome these ailments. RESULTS: There is growing body of evidence that suggests surprisingly high vulnerability within the dental profession to certain disorders and afflictions that can be categorized as practice-related. CONCLUSIONS: In different countries dentists reported having poor general health and suffer from various health-related problems. To enjoy and be satisfied with their professional and personal lives, dentists must be aware of the importance to maintain good physical and mental health.  相似文献   
96.
BACKGROUND: Iron chelation therapy (ICT) with deferoxamine (DFO), the current standard for the treatment of iron overload in patients with transfusion-dependent disorders such as beta-thalassemia, requires regular subcutaneous or intravenous infusions. This can lead to reduced quality of life and poor adherence, resulting in increased morbidity and mortality in iron-overloaded patients with beta-thalassemia. Deferasirox is an orally administered iron chelator that has been approved for use in the United States, Switzerland, and other countries. OBJECTIVE: This analysis was conducted to compare patient-reported outcomes (PROs) during receipt of DFO infusions or once-daily oral therapy with deferasirox (ICL670). METHODS: PROs were prospectively evaluated as part of a randomized, Phase III study comparing the efficacy and safety profile of DFO 20 to 60 mg/kg per day with those of deferasirox 5 to 30 mg/kg per day in patients (age > or =2 years) with beta-thalassemia who were receiving regular transfusions and had a liver iron concentration of > or =2 mg/g dry weight. PRO questionnaires were completed by patients or a parent or legal guardian at baseline, week 4, week 24, and end of study (EOS). Patients assessed their level of satisfaction with study treatment (very satisfied, satisfied, neutral, dissatisfied, or very dissatisfied) and rated its convenience (very convenient, convenient, neutral, inconvenient, or very inconvenient). Time lost from normal activities due to ICT in the previous 4 weeks was recorded using a single global assessment. At week 4, patients who had previous experience with DFO were asked to indicate their preference for treatment (ICT received before the study, ICT received during the study, no preference, or no response) and the reason for that preference. At EOS, all patients were asked if they would be willing to continue using the ICT they had received during the study. All study analyses were performed in all patients who received at least 1 dose of study medication. RESULTS: Five hundred eighty-six patients (304 females, 282 males; age range, 2-53 years) received treatment with DFO (n = 290) or deferasirox (n = 296). Significantly more patients treated with deferasirox reported being very satisfied or satisfied with treatment compared with those treated with DFO (week 4: 92.0% vs 50.4%, respectively; week 24: 89.6% vs 44.0%; EOS: 85.1% vs 38.7%; all, P < 0.001). At the same time points, the majority of those treated with deferasirox reported that treatment was very convenient or convenient compared with those treated with DFO (95.5% vs 21.3%, 91.7% vs 17.4%, and 92.7% vs 11.3%, respectively; all, P < 0.001). Among patients who had previously taken DFO and were randomized to receive deferasirox during the study, 96.9% reported a preference for deferasirox over DFO. At EOS, the proportion of patients indicating a willingness to continue study therapy was significantly greater in those receiving deferasirox than in those receiving DFO (85.8% vs 13.8%; P < 0.001). CONCLUSIONS: In this study, patient-reported satisfaction and convenience were significantly higher for the once-daily, oral ICT deferasirox than for DFO infusions. Among patients who had received DFO before the study, the majority indicated a preference for deferasirox over DFO. Most patients receiving deferasirox indicated that they would be willing to continue taking it. These results suggest that deferasirox had a positive impact on patients' daily lives.  相似文献   
97.
International Urology and Nephrology - The association between end-stage renal disease and cardiovascular mortality may be influenced through vascular alterations, in particular atherosclerosis and...  相似文献   
98.
Redo mitral valve replacement remains the standard treatment for recurrent mitral valve disease. Most patients referred for a redo surgery in the western world are older and present with multiple comorbidities. With the successful broad implementation of anti-infective treatment, rheumatic mitral valve disease has become highly uncommon. Nonetheless, rheumatic heart disease is still thriving in developing countries causing the most severe mitral valve conditions. The guidelines are there to help us in our decision-making process, but the actual decision has to be made based on each patients' individual criteria.  相似文献   
99.
The study of congenitally deaf individuals provides a unique opportunity to understand the organization and potential for reorganization of human auditory cortex. We used magnetic resonance imaging (MRI) to examine the structural organization of two auditory cortical regions, Heschl's gyrus (HG) and the planum temporale (PT), in deaf and hearing subjects. The results show preservation of cortical volume in HG and PT of deaf subjects deprived of auditory input since birth. Measurements of grey and white matter, as well as the location and extent of these regions in the deaf showed complete overlap both with matched controls and with previous samples of hearing subjects. The results of the manual volume measures were supported by findings from voxel-based morphometry analyses that showed increased grey-matter density in the left motor hand area of the deaf, but no differences between the groups in any auditory cortical region. This increased cortical density in motor cortex may be related to more active use of the dominant hand in signed languages. Most importantly, expected interhemispheric asymmetries in HG and PT thought to be related to auditory language processing were preserved in these deaf subjects. These findings suggest a strong genetic component in the development and maintenance of auditory cortical asymmetries that does not depend on auditory language experience. Preservation of cortical volume in the deaf suggests plasticity in the input and output of auditory cortex that could include language-specific or more general-purpose information from other sensory modalities.  相似文献   
100.
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