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41.
This study investigated how mothers’ attachment was related to their responses to their own and their children’s positive events and positive affect (PA). Ninety-seven mothers reported on their attachment and their responses to their own and their 7–12-year-old children’s positive events and emotions. Children reported on their mothers’ responses to the children’s positive events and their attachment security with their mothers. The results indicated that more avoidant mothers reported less intense PA in response to their own and their children’s positive events. More avoidant mothers also were less likely to encourage their children to savor positive events (through expressing PA, reflecting on PA or themselves, giving rewards, and affectionate responses). Mothers higher on anxiety reported greater likelihood of dampening (e.g., minimizing the event’s importance) their own positive events and reported being more likely to feel discomfort and to reprimand their children for expressing PA. Children’s security was predicted by mothers’ lower likelihood of encouraging children’s dampening and of reprimanding children for PA displays. This study advances the literature on how mothers’ attachment is related to the ways in which they regulate their own and their children’s PA, which may have implications for children’s attachment and developing PA regulation.  相似文献   
42.
43.

Background

Older people living in care homes often have limited life expectancy. Practitioners and policymakers are increasingly questioning the appropriateness of many acute hospital admissions and the quality of end-of-life care provided in care homes.

Aim

To describe care home residents’ trajectories to death and care provision in their final weeks of life.

Design and setting

Prospective study of residents in six residential care homes in three sociodemographically varied English localities: Hertfordshire, Essex, and Cambridgeshire.

Method

Case note reviews and interviews with residents, care home staff, and healthcare professionals.

Results

Twenty-three out of 121 recruited residents died during the study period. Four trajectories to death were identified: ‘anticipated dying’ with an identifiable end-of-life care period and death in the care home (n = 9); ‘unexpected dying’ with death in the care home that was not anticipated and often sudden (n = 3); ‘uncertain dying’ with a period of diagnostic uncertainty or difficult symptom management leading to hospital admission and inpatient death (n = 7); and ‘unpredictable dying’ with an unexpected event leading to hospital admission and inpatient death (n = 4). End-of-life care tools were rarely used. Most residents who had had one or more acute hospital admission were still alive at the end of the study.

Conclusion

For some care home residents there was an identifiable period when they were approaching the end-of-life and planned care was put in place. For others, death came unexpectedly or during a period of considerable uncertainty, with care largely unplanned and reactive to events.  相似文献   
44.
The purpose of this study was to determine how the mechanical efficiency of skeletal muscle is affected by level of activation. Experiments were performed in vitro (35 °C) using bundles of fibres from fast-twitch extensor digitorum longus (EDL) and slow-twitch soleus muscles of mice. Measurements were made of the total work and heat produced in response to 10 brief contractions. Mechanical efficiency was the ratio of total work performed to (total heat produced + work performed). Level of activation was varied by altering stimulation frequency between 40 and 160 Hz. Efficiency did not differ significantly between the two muscle types but was significantly lower using 40 Hz stimulation (mean efficiency ± SEM, 0.092?±?0.012, n?=?12, averaged across EDL and soleus) than at any of the other frequencies (160 Hz: 0.147?±?0.007, n?=?12). Measurements of the partitioning of energy output between force-dependent and force-independent components enabled calculation of the amount of Ca2+ released and number of cross-bridge cycles performed during the contractions. At 40 Hz stimulation frequency, less Ca2+ was released than at higher frequencies and fewer cross-bridge cycles were performed. Furthermore, less work was performed in each cross-bridge cycle. It is concluded that skeletal muscles are less efficient at low levels of activation than when fully activated and this indicates that level of activation affects not only the number of cycling cross-bridges but also the ability of individual cross-bridges to perform work.  相似文献   
45.
Cutaneous leishmaniasis is rarely seen in the United States. Four Cuban immigrants traveled along the same route at different times from Cuba to Ecuador, then northward, including through the Darién Jungle in Panama. These patients had chronic ulcerative non-healing skin lesions and were given a diagnosis of leishmaniasis.Leishmaniasis is a vector-borne disease caused by the protozoan parasite of the genus Leishmania and is spread by the bite of sand flies from the sub-family Phlebotominae.1 There are various clinical manifestations of leishmaniasis, including cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis, and visceral leishmaniasis. Cutaneous leishmaniasis occurs at the site of the bite, with lesions forming weeks to months later starting with a papule, which then develops into a nodule or plaque-like lesion and progresses to a painless ulceration with an indurated border.We report four cases of CL caused by Leishmania (Viannia) panamensis in Cuban immigrants who traveled through the Darién Gap Jungle between Colombia and Panama on their journey north to the United States. This region has been shown to have high transmission rates of leishmaniasis,2 and, in 2012, Panama experienced an outbreak beyond expected endemic rates.3 This case series highlights a previously underappreciated immigration route to the United States for Cubans and the need to include leishmaniasis as a differential diagnosis for non-healing skin ulcers in this patient population.During May 2012–April 2013, four persons who had recently immigrated to the United States from Cuba came to the National School of Tropical Medicine at Baylor College of Medicine''s (BCM) Tropical Medicine Clinic for non-healing skin ulcers. All four persons reported a similar route of travel from Cuba to Texas (Figure 1), although at different times. Each person began their journey by flying to Quito, Ecuador, where they then traveled by bus through Colombia, passing through the cities of Pasto and Cali to Quibdo. In Quibdo, they took a short flight to Bahia Solano, Colombia, where a boat ride then transported them to Punta Ardita near the Panama border. They then traveled by foot through the thick jungle in Darién, Panama, for 5–15 days. During this time, they slept outdoors and reported numerous insect bites. Once through the Darién area, they traveled northward until they entered the United States at the Mexican border.Open in a separate windowFigure 1.Map showing immigration route of a cluster of Cuban patients with cutaneous leishmaniasis caused by Leishmania (V.) panamensis. Note the travel by foot through the thick jungle of the Darién National Park, Panama, where they likely contracted the disease.Once in the United States, the four persons sought medical care at outside clinics for skin lesions that had developed within two months after they passed though the Darién. They were treated for presumed infection with Staphylococcus aureus. The antibiotics had no therapeutic effect, and the lesions continued to grow and develop into non-healing, painless ulcers with accompanying satellite lesions. Once in Houston, Texas, the four persons were directed to the Department of Dermatology at BCM (
PatientAge, years/sexLesion location; size; presence of satellite lesions (+/−)Diagnosis and pathogenDuration of disease before initiation of treatmentTreatment course
138/FProximal right posterior arm; 5 cm; (+)CL L. (V.) panamensis3 monthsAmBisome (days 1–5, 14, 21)
246/MDistal left forearm; 2 lesions: 4 cm and 3 cm; (+)CL L. (V.) panamensis2 monthsAmBisome (days 1–5, 14, 21); then itraconazole (daily, 30 days)
343/MVertex of scalp, 8 more lesions on eyes, legs, and torso; 5 cm, other lesions 1 cm; (+)CL L. (V.) panamensis2 weeksAmBisome (days 1–5); then pentostam (daily, 20 days)
443/FLeft malar area; 1.5 cm; (+)CL L. (V.) panamensis3 monthsAmBisome (days 1–5, 14)
Open in a separate window*CL = cutaneous leishmaniasis.Patient 1 was a 38-year old woman with a three-month history of an expanding, painless, pruritic ulcer who had a 5-cm ulcer on her proximal right arm, along with several satellite lesions covered with crusts, as well as a 1.5-cm erythematous papule with central ulceration covered in crust on her right thigh. Patient 2 was a 46-year old man who had a two-month history of two erythematous, scaly plaques with central ulceration on the left forearm (Figure 2A). Patient 3 was 43-year old man with a two-month history of non-healing, tender lesions that on presentation were a 5-cm crusted nodule at the vertex of the patient''s scalp and two right parietal 1 cm papules, as well as a fluctuant nodule on his right lower leg. Patient 4 was a 43-year old woman who had a two-month history of a slowly expanding, painless lesion on her cheek, which on examination was a 1.5-cm eroded nodule on her left malar area and four papules above the main lesion (Figure 2C). All of the patients reported the lesions appearing from two weeks to two months after traveling through the Darién area. No lesions were noted before traveling through this region. The patients all denied systemic complaints including fevers, chills, night sweats, and weight loss, and were otherwise normal on physical exam. No mucosal involvement was noted in any of the patients upon exam.Open in a separate windowFigure 2.Skin ulcers of two of the four Cuban immigrants to the United States with cutaneous leishmaniasis caused by Leishmania (V.) panamensis. A, Patient 2 , showing two erythematous, scaly plaques with central ulceration and diameters of 3 cm and 4 cm on the left forearm. B, Patient 2 at six months post-treatment showing good resolution of the lesions. C, Patient 4, showing a 1.5-cm eroded nodule on left malar area and four papules above the main lesion. D, Patient 4 at three months post treatment showing with good resolution of the lesions.For each of the patients, a punch biopsy was performed by the Department of Dermatology for diagnosis by histologic analysis by BCM, and species-specific polymerase chain reaction and culture performed by the Centers for Disease Control and Prevention (Atlanta, GA). All biopsy specimens showed dense inflammatory infiltrates in the dermis with numerous histiocytes, lymphocytes, and intracellular structures within macrophages. These structures were identified as small organisms with kinetoplasts suggestive of Leishmania amastigotes. Numerous dermal plasma cells were also seen in biopsy specimens from patients 1, 2, and 4. Biopsy specimens from patient 3 showed dermal multinucleated giant cells, and scattered dermal eosinophils were observed in biopsy specimens from patient 4. Using polymerase chain reaction, PCR, CDC identified L. (V.) panamensis, a parasitic infection found in Belize, Colombia, Costa Rica, Ecuador, Honduras, Nicaragua, Panama, and Venezuela.4All the patients were treated with liposomal amphotericin B (AmBisome), 3 mg/kg/day for 5 days, followed by two infusions at the same dose on days 14 and 21 to complete a total treatment of 21 mg/kg,5 a dosing found to be effective in treating CL.6 In an attempt to minimize infusion-related reactions, the patients were pre-treated with 50 mg of diphenhydramine and 650 mg of acetaminophen, and hydrated with 500 mL of normal saline before each infusion.6 Despite this treatment, patient 1 experienced a mild self-resolving infusion-related reaction with chills and a headache. Three patients experienced an elevation of the creatinine level (two times the reference value) that resolved within days.Patients were followed-up by the Tropical Medicine Clinic over several months because healing of these ulcers is slow. Patients 1 and 4 had good resolution (Figure 2D), and patient 2 had a small, 1-cm, dry, scabbed lesion at five months post-treatment. Concern over incomplete resolution led to a 30 day course of itraconazole, 200 mg twice a day, which led to good resolution of the lesion and a leishmaniasis-negative biopsy result (Figure 2B). Patient 3 had the most extensive disease, with 13 lesions upon presentation, and during his treatment with liposomal amphotericin B, continued to have disease progression. Concern for treatment failure led to additional therapy with intravenous sodium stibogluconate (pentostam), starting at 50% of the dose (10 mg/kg/day), and increasing to 75% (15 mg/kg/day) on day 5, then 100% (20 mg/kg/day) on day 10 to complete a total of 20 days of therapy, as recommended by the Parasitic Diseases Branch of CDC (personal communication). Currently, his lesions are resolving well.Liposomal amphotericin B was chosen because all patients had extensive disease, and in the case of patient 4, the lesion was on her face, where scarring is undesirable. Liposomal amphotericin B therapy for CL has been shown clinically to be effective, with improved lesion resolution and less toxicity than sodium stibogluconate.1,612 Treatment not only promotes healing of the cutaneous lesion, but also reduces the risk of subsequent mucosal involvement.13,14 Up to 12% of CL cases are at risk of later developing mucocutaneous leishmaniasis, depending on the subspecies of Leishmania Viannia; either braziliensis or guyanensis have the highest risk.15 Mucocutaneous leishmaniasis presents as cutaneous lesions in addition to mucosal destruction, most commonly of the nose, mouth, or nasal septum. Mucosal destruction can be disfiguring and may occur years after the development of cutaneous lesions.This report highlights a previously underappreciated immigration route for Cubans through Central America, which places immigrants at risk for a number of emerging tropical diseases, including leishmaniasis. Physicians should be aware of this immigration route when treating Cuban immigrants and include leishmaniasis in the differential diagnosis when treating non-healing skin ulcers in this patient population. Liposomal amphotericin B can be a well-tolerated and efficacious treatment of CL caused by L. (V.) panamensis.  相似文献   
46.
The spectrum of perianal Crohn's disease in a population-based cohort     
Eglinton TW  Barclay ML  Gearry RB  Frizelle FA 《Diseases of the colon and rectum》2012,55(7):773-777
  相似文献   
47.
Regulatory element copy number differences shape primate expression profiles     
RC Iskow  O Gokcumen  A Abyzov  J Malukiewicz  Q Zhu  AT Sukumar  AA Pai  RE Mills  L Habegger  DA Cusanovich  MA Rubel  GH Perry  M Gerstein  AC Stone  Y Gilad  C Lee 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(31):12656-12661
Gene expression differences are shaped by selective pressures and contribute to phenotypic differences between species. We identified 964 copy number differences (CNDs) of conserved sequences across three primate species and examined their potential effects on gene expression profiles. Samples with copy number different genes had significantly different expression than samples with neutral copy number. Genes encoding regulatory molecules differed in copy number and were associated with significant expression differences. Additionally, we identified 127 CNDs that were processed pseudogenes and some of which were expressed. Furthermore, there were copy number-different regulatory regions such as ultraconserved elements and long intergenic noncoding RNAs with the potential to affect expression. We postulate that CNDs of these conserved sequences fine-tune developmental pathways by altering the levels of RNA.  相似文献   
48.
Comparison of the Diamond-Forrester method and Duke Clinical Score to predict obstructive coronary artery disease by computed tomographic angiography     
Wasfy MM  Brady TJ  Abbara S  Nasir K  Ghoshhajra BB  Truong QA  Hoffmann U  Di Carli MF  Blankstein R 《The American journal of cardiology》2012,109(7):998-1004
We sought to evaluate the ability of the Diamond and Forrester method (DFM) and the Duke Clinical Score (DCS) to predict obstructive coronary artery disease (CAD) on coronary computed tomographic angiography (CCTA) and the effect of these different risk scores on the appropriateness level using the 2010 Appropriate Use Criteria. Consecutive symptomatic patients who underwent CCTA for evaluation of CAD (n = 114) were classified as having a low, intermediate, or high pretest probability using the DFM and DCS. Using the Appropriate Use Criteria, the indications for CCTA were classified according to the pretest probability and previous testing. The CCTA results were classified as revealing obstructive (≥70% stenosis), nonobstructive (<70%), or no CAD. When the patients' risk was classified using the DFM, 18% were low, 65% intermediate, and 17% high risk. When using the DCS, 53% of patients had a reclassification of their risk, most of whom changed from intermediate to either low or high risk (50% low, 19% intermediate, 35% high risk). The net reclassification improvement for the prediction of obstructive CAD was 51% (p = 0.01). Of the 37 patients who were reclassified as low risk, 36 (97%) lacked obstructive CAD. Appropriateness for CCTA was reclassified for 13% of patients when using the DCS instead of the DFM, and the number of appropriate examinations was significantly fewer (68% vs 55%, p <0.001). In conclusion, reclassification of risk using the DCS instead of the DFM resulted in improved prediction of obstructive CAD on CCTA, especially in low-risk patients. More patients were categorized as having a high pretest probability of CAD, resulting in reclassification of their examination indications as uncertain or inappropriate. These results identify the need for improved pretest risk scores for noninvasive tests such as CCTA and suggest that the method of risk assessment could have important implications for patient selection and quality assurance programs.  相似文献   
49.
Long-term alteration in maternal blood pressure and renal function after pregnancy in normal and growth-restricted rats     
Gallo LA  Denton KM  Moritz KM  Tare M  Parkington HC  Davies M  Tran M  Jefferies AJ  Wlodek ME 《Hypertension》2012,60(1):206-213
Intrauterine growth restriction is associated with increased risk of adult cardiorenal diseases. Small birth weight females are more likely to experience complications during their own pregnancy, including pregnancy-induced hypertension, preeclampsia, and gestational diabetes. We determined whether the physiological demand of pregnancy predisposes growth-restricted females to cardiovascular and renal dysfunction later in life. Late gestation bilateral uterine vessel ligation was performed in Wistar-Kyoto rats. At 4 months, restricted and control female offspring were mated with normal males and delivered naturally (ex-pregnant). Regardless of maternal birth weight, at 13 months, ex-pregnant females developed elevated mean arterial pressure (indwelling tail-artery catheter; +6 mm Hg), reduced effective renal blood flow ((14)C-PAH clearance; -23%), and increased renal vascular resistance (+27%) compared with age-matched virgins. Glomerular filtration rate ((3)H-inulin clearance) was not different across groups. This adverse cardiorenal phenotype in ex-pregnant females was associated with elevated systemic (+57%) and altered intrarenal components of the renin-angiotensin system. After pregnancy at 13 months, coronary flow (Langendorff preparation) was halved in restricted females compared with controls, and together with reduced NO excretion, this may increase susceptibility to additional lifestyle challenges. Our results have implications for aging females who have been pregnant, suggesting long-term cardiovascular and renal alterations, with additional consequences for females who were small at birth.  相似文献   
50.
Immune Responses to the O-Specific Polysaccharide Antigen in Children Who Received a Killed Oral Cholera Vaccine Compared to Responses following Natural Cholera Infection in Bangladesh     
Daniel T. Leung  Taher Uddin  Peng Xu  Amena Aktar  Russell A. Johnson  Mohammad Arif Rahman  Mohammad Murshid Alam  Meagan Kelly Bufano  Grace Eckhoff  Ying Wu-Freeman  Yanan Yu  Tania Sultana  Farhana Khanam  Amit Saha  Fahima Chowdhury  Ashraf I. Khan  Richelle C. Charles  Regina C. LaRocque  Jason B. Harris  Stephen B. Calderwood  Pavol Ková?  Firdausi Qadri  Edward T. Ryan 《Clinical and Vaccine Immunology : CVI》2013,20(6):780-788
Current oral cholera vaccines induce lower levels of protective efficacy and shorter durations of protection in young children than in adults. Immunity against cholera is serogroup specific, and immune responses to Vibrio cholerae lipopolysaccharide (LPS), the antigen that mediates serogroup-specific responses, are associated with protection against disease. Despite this, responses against V. cholerae O-specific polysaccharide (OSP), a key component of the LPS responsible for specificity, have not been characterized in children. Here, we report a comparison of polysaccharide antibody responses in children from a region in Bangladesh where cholera is endemic, including infants (6 to 23 months, n = 15), young children (24 to 59 months, n = 14), and older children (5 to 15 years, n = 23) who received two doses of a killed oral cholera vaccine 14 days apart. We found that infants and young children receiving the vaccine did not mount an IgG, IgA, or IgM antibody response to V. cholerae OSP or LPS, whereas older children showed significant responses. In comparison to the vaccinees, young children with wild-type V. cholerae O1 Ogawa infection did mount significant antibody responses against OSP and LPS. We also demonstrated that OSP responses correlated with age in vaccinees, but not in cholera patients, reflecting the ability of even young children with wild-type cholera to develop OSP responses. These differences might contribute to the lower efficacy of protection rendered by vaccination than by wild-type disease in young children and suggest that efforts to improve lipopolysaccharide-specific responses might be critical for achieving optimal cholera vaccine efficacy in this younger age group.  相似文献   
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