To maintain the intracellular concentration of ions and small molecules on osmotic challenges, nature has developed highly sophisticated transport systems for regulating water and ion content. An ideal measurement technique for volume changes of cells during osmotic challenges has to fulfil two requirements: it has to be osmotically inert, and it should allow online monitoring of cell volume changes. Here, a simple fluorescence microscopy-based approach is presented. Using fluorescein as a negative stain, it is possible to monitor cell volume changes without affecting the functionality of cell membranes and cell osmolarity. Measurement of Madine-Darby canine kidney (MDCK) cells after hypo- and hyperosmotic challenges reveals the main advantages of this approach: besides providing precise and reproducible quantitative data on reversible cell volume changes, the viability of the cells can be assessed directly by the appearance of stain in the cytoplasm. This becomes evident especially after hypo-osmotic challenge of glutaraldehyde-treated cells, which become leaky after fixation, followed by a massive volume change. This new approach represents a very sensitive measurement technique for cell volume changes resulting from water or ion flux, and thus seems to be an ideal tool for studying cell volume regulatory processes. 相似文献
Thirteen Spanish families with autosomal dominant polycystic kidney disease were studied. In one family the disease did not segregate with polymorphic markers around the PKD1 locus. All subjects over the age of 30 years carrying a mutation at the PKD1 locus showed renal ultrasonographic cysts, but 40% of carriers of the PKD1 mutation younger than 30 years did not have renal cysts. Hypertension was found to be more frequent in those with renal cysts. Recombinants between 16p polymorphic loci and the PKD1 locus are described. 相似文献
Constitutional mutations in the RB1 gene predispose to retinoblastoma development. Hence genetic screening of retinoblastoma patients and relatives is important for genetic counseling purposes. In addition, RB1 gene mutation studies may help decipher the molecular mechanisms leading to tumors with different degrees of penetrance or expressivity. In the course of genetically screening of 107 hereditary and non-hereditary retinoblastoma patients (11 familiar bilateral, 4 familiar unilateral, 49 sporadic bilateral and 43 sporadic unilateral) and kindred from Spain, Colombia and Cuba, using direct PCR sequencing, we observed 45 distinct mutations and four RB1 deletions in 53 patients (9 familiar bilateral, 2 familiar unilateral, 31 sporadic bilateral and 11 sporadic unilateral). Most of these mutations (26/45, 57%) have not been reported before. In 32 patients, the predisposing mutations correspond to nonsense (mainly CpG transitions) and small insertions or deletions whose expected outcome is a truncated Rb protein that lacks the functional pockets and tail. Five single aminoacid replacements and seventeen mutations affecting splicing sites were also observed in retinoblastoma patients. Two of these sixteen mutations are of unclear pathogenic nature. 相似文献
BACKGROUND: This study was conducted on human cervical mucus using light microscopy (LM) and scanning electron microscopy (SEM). The objective was the morphological characterization of the different mucus types, with samples taken from the lumen of the cervix and from the different secretory zones of the cervical mucosa. METHODS: A total of 230 samples from 195 women were spread out on slides and air dried. The phenomenon of 'ferning' was observed and assessed in these samples using both LM and SEM. Further samples from the lumen of the cervix and the different secretory crypts were spread out on cover slips and fixed with glutaraldehyde (2.5%) to be studied by SEM. RESULTS: The results show the presence of four different morphological mucus types, namely L, S, P and G, in both types of sample using dried and fixed techniques. CONCLUSIONS: Mucus from the lumen of the cervix appears to be a morphologically heterogeneous entity. It contains different types of secretions, the proportions of which vary throughout the menstrual cycle. The different mucosal types show different types of crystallization, different patterns of ultrastructure (probably related to the arrangement of the glycoprotein network) and are produced in different secretory zones of the crypts in the cervix. 相似文献
A dense osmiophilic structure was found associated to the basal lamina of the outer limiting glial membrane of the carp olfactory bulb. In certain sections this material appears as "beads" composed of small strand-like structures, and in others it seems to form a palisade-like structure. The possible origin and function of this structure is discussed. 相似文献
Recent evidence suggests that among behavioral-lifestyle factors, adherence to a healthy dietary pattern such as the Mediterranean Diet (MedDiet) is linked not only to better psychological health and mental positive status but also to increased subjective well-being (SWB). Nevertheless, this association has been unexplored among individuals with excessive weight. This study explored whether adherence to the MedDiet and the intake of healthy foods such as fruits and vegetables (FV) are associated with increased happiness and life satisfaction among Spanish adults with overweight or obesity when weight, body image, and body satisfaction are also considered. A convenience sample of adult individuals with excessive weight completed self-reports on the study variables, and weight and BMI were measured by bioimpedance. No evidence of a relationship with SWB indicators was obtained for MedDiet global indicators, probably due to the low adherence to a healthy diet by these individuals. In contrast, FV intake, as a powerful indicator of healthy eating, was associated with life satisfaction when BMI and body image dimensions were considered, among which body satisfaction had a key role. Moreover, life satisfaction fully mediated the relationship between FV consumption and happiness. Our findings are expected to make a relevant contribution to knowledge on the positive correlates or protective factors for overall well-being in obesity, including dietary habits and body appreciation. Our results may inform obesity management actions focused on inclusive, positive aesthetic models and promoting a healthy lifestyle for happiness in obesity. 相似文献
The Eastern Mediterranean Region (EMR) is experiencing a nutrition transition, characterized by the emergence of overnutrition and micro-nutrient deficiencies. No previous study has comparatively examined nutrient intake in adults across countries in the EMR. This review examined the adequacy of nutrients in adults living in the EMR. Moreover, it analyzed the food balance sheets (FBS) for 1961–2018 to identify the trajectory of energy supply from macro-nutrients in the EMR. A systematic search was conducted from January 2012 to September 2020. Only observational studies were retained with a random sampling design. An assessment of the methodological quality was conducted. Levels of nutrient daily intake and their adequacy compared to the daily reference intake of the Institute of Medicine were reported across the region. No studies were identified for half of the region’s countries. Although nutrient energy intake was satisfactory overall, fat and carbohydrate intake were high. Intake of vitamin D, calcium, potassium, zinc, and magnesium were below that recommended. The analysis of the FBS data allowed for the identification of four linear patterns of trajectories, with countries in the EMR best fitting the ‘high-energy-supply from carbohydrate’ group. This systematic review warrants multi-sectorial commitment to optimize nutrient intake. 相似文献
Medicine, Health Care and Philosophy - Biomedical innovations are making possible the enhancement of human capabilities. There are two philosophical stances on the role that medicine should play in... 相似文献
Healthcare personnel are recognized to be at higher risk for infection with severe acute respiratory syndrome coronavirus 2. We conducted a serologic survey in 15 hospitals and 56 nursing homes across Rhode Island, USA, during July 17–August 28, 2020. Overall seropositivity among 9,863 healthcare personnel was 4.6% (95% CI 4.2%–5.0%) but varied 4-fold between hospital personnel (3.1%, 95% CI 2.7%–3.5%) and nursing home personnel (13.1%, 95% CI 11.5%–14.9%). Within nursing homes, prevalence was highest among personnel working in coronavirus disease units (24.1%; 95% CI 20.6%–27.8%). Adjusted analysis showed that in hospitals, nurses and receptionists/medical assistants had a higher likelihood of seropositivity than physicians. In nursing homes, nursing assistants and social workers/case managers had higher likelihoods of seropositivity than occupational/physical/speech therapists. Nursing home personnel in all occupations had elevated seropositivity compared with hospital counterparts. Additional mitigation strategies are needed to protect nursing home personnel from infection, regardless of occupation. 相似文献
Studies have shown mixed findings regarding the impact of immigration policy changes on immigrants’ utilization of primary care.
Methods
We used a difference-in-differences analysis to compare changes in missed primary care appointments over time across two groups: patients who received care in Spanish, Portuguese, or Haitian Creole, and non-Hispanic, white patients who received care in English.
Results
After adjustment for age, sex, race, insurance, hospital system, and presence of chronic conditions, immigration policy changes were associated with an absolute increase in the missed appointment prevalence of 0.74 percentage points (95% confidence interval: 0.34, 1.15) among Spanish, Portuguese and Haitian-Creole speakers. We estimated that missed appointments due to immigration policy changes resulted in lost revenue of over $185,000.
Conclusions
We conclude that immigration policy changes were associated with a significant increase in missed appointments among patients who receive medical care in languages other than English.