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101.
Leptin, the ob gene product, plays an important role in the regulation of body fat mass and weight. In previous studies, it was demonstrated that leptin is detectable in human fetal cord blood as early as at 18 weeks of gestation and that serum leptin concentrations are significantly reduced in small gestational age newborns. In the present study, we investigated whether umbilical and maternal serum leptin concentrations correlate with intrauterine growth retardation (IUGR). In addition, we aimed to determine the relationships between leptin concentration in the maternal and cord blood. We studied 40 newborn infants (21 female and 19 male; gestational age, 38-42 weeks) and their mothers. Of the infants studied, 10 had IUGR. Serum leptin concentrations were measured by radioimmunoassay. All newborns had detectable leptin concentrations. Leptin concentrations were significantly lower in newborns with IUGR and in their mothers (n = 10; 3.53 +/- 1.42 ng/ml, 6.75 +/- 1.47 ng/ml, respectively) than in infants experiencing normal growth and their mothers (n = 30; 5.58 +/- 2.98 ng/ml, 9.85 +/- 6.50 ng/ml, respectively) (p < 0.01 for newborns, p < 0.05 for mothers). There was no significant correlation between umbilical leptin concentration and maternal leptin concentration (r = 0.229; p = 0.155) in all study groups but, significantly, a correlation was observed in the group with IUGR (r = 0.736; p = 0.015). There were no significant correlations between both umbilical and maternal leptin concentrations and parity, delivery type and gestational age. There was a correlation between umbilical leptin concentration and birth weight of newborns (r = 0.383; p = 0.015) but no correlation with body mass index (BMI) of the newborns (r = 0.034; p = 0.834). Maternal leptin concentrations correlated with maternal weight and BMI (r=0.606; p=0.000, r=0.535; p=0.000, respectively). There was no correlation between maternal leptin concentrations and birth weight of the newborns (r=0.179; p=0.269) and with BMI of the newborns (r = 0.146; p = 0.367). There was no gender difference in leptin concentrations in the newborns (n=21; 5.50 +/- 3.37 ng/ml, for females; n = 19; 4.58 +/- 1.98 ng/ml for males) (p = 0.296). In summary, we have shown that IUGR is associated with a decreased leptin concentration in newborns and their mothers. The association between umbilical serum leptin and birth weight in this and other studies suggests a pivotal role of fetal leptin in regulating fetal growth and development.  相似文献   
102.
Introduction: Patients with inadequately controlled or uncontrolled asthma are at a greater risk of attacks for asthma requiring emergency room visits or hospital admissions. There is a significant correlation between the severity of the disease and the severity of exacerbations. Patients with poorly controlled asthma are at a higher risk for complications. Case study: We present a 24-year-old aspirin-intolerant, uncontrolled asthma patient with the complication of pneumomediastinum. Results: Severe symptoms persisted after the resolution of the pneumomediastinum despite intense anti-inflammatory and anti-obstructive therapy. A bronchoscopy revealed an endobronchial lesion and she was diagnosed with a carcinoid tumor. Conclusion: This case is an example of the importance of re-evaluating asthma patients who do not respond to standard medical treatment. Clinicians should be aware of the complications associated with asthma attacks such as pneumomediastinum and the possibility of a differential diagnosis that worsen asthma symptoms such as a carcinoid tumor.  相似文献   
103.
The fossil record of carnivorous plants is very scarce and macrofossil evidence has been restricted to seeds of the extant aquatic genus Aldrovanda of the Droseraceae family. No case of carnivorous plant traps has so far been reported from the fossil record. Here, we present two angiosperm leaves enclosed in a piece of Eocene Baltic amber that share relevant morphological features with extant Roridulaceae, a carnivorous plant family that is today endemic to the Cape flora of South Africa. Modern Roridula species are unique among carnivorous plants as they digest prey in a complex mutualistic association in which the prey-derived nutrient uptake depends on heteropteran insects. As in extant Roridula, the fossil leaves possess two types of plant trichomes, including unicellular hairs and five size classes of multicellular stalked glands (or tentacles) with an apical pore. The apices of the narrow and perfectly tapered fossil leaves end in a single tentacle, as in both modern Roridula species. The glandular hairs of the fossils are restricted to the leaf margins and to the abaxial lamina, as in extant Roridula gorgonias. Our discovery supports current molecular age estimates for Roridulaceae and suggests a wide Eocene distribution of roridulid plants.Plant carnivory is traditionally defined as the attraction, capture, and digestion of prey by vegetative traps, with the subsequent uptake of nutrients (1, 2). Some carnivorous plants, however, challenge the boundary of the botanical carnivory concept because they depend on commensal organisms for the digestion of their prey (2, 3). The most famous representative of those plants is Roridula, placed in the monogeneric family Roridulaceae that is endemic to a few localities in the southwestern Cape of South Africa (4, 5).The resinous glandular leaves of both extant species, Roridula dentata and Roridula gorgonias, capture plenty of arthropods. The sticky trapping glue of Roridula is a viscous lipophilic resin containing triterpenoids as major component, which does not allow dissolution of digestive enzymes (6). Consequently, the secretory glands of Roridulaceae lack enzymatic activity (7, 8). For prey-derived nutrient uptake, Roridula depends on two obligately associated heteropteran Pameridea species (family Miridae, “capsid bugs”), which feed on the trapped animals (5, 9). In this “digestive mutualism” (10), the nutrient-rich fecal compounds of these “Roridula bugs” are incorporated by Roridula through nanometer-sized cuticular gaps and serve for a better alimentation in a nutrient-poor habitat (7, 8, 10, 11). The benefit of nutrient uptake from captured prey is the essential criterion for the concept of botanical carnivory (1, 2) and thus includes Roridulaceae (11, 12).Here, we report two leaf fossils from Eocene Baltic amber possessing the relevant morphological features of an adhesive flypaper trap plant that we assign to the Roridulaceae lineage (Figs. 13). Both specimens originate from the Jantarny amber mine near Kaliningrad (Russia). The amber-bearing sediments of this fossil site date to 35–47 million years ago (13, 14).Open in a separate windowFig. 1.Carnivorous leaves from Eocene Baltic amber. (A) Overview of the leaf enclosed in amber specimen GZG.BST.27310 showing the adaxial tentacle-free side in slightly oblique view and stalked glands at the margin and on the abaxial side; arrowhead points to the exceptional long tentacle stalk with several branched oak trichomes attached. (B) Overview of the leaf enclosed in amber specimen GZG.BST.27311, showing abundant tentacles on the abaxial side. (C) Margin of abaxial leaf surface with tentacles of different size classes and nonglandular hyaline trichomes. (D) Leaf apex tapering into a sole tentacle. (E and F) Glandular heads with central pore (arrowheads) from both leaves. (Scale bars: A and B, 1 mm; C and D, 100 µm; E, 10 μm; F, 40 μm.)Open in a separate windowFig. 3.Carnivorous leaf from Eocene Baltic amber (A and B; GZG.BST.27310) and leaves of extant Roridula gorgonias (C and D). (A) Exceptionally long tentacle stalk (with several branched oak trichomes attached) of the fossil leaf representing the fifth size class of stalked glands. (B and C) Overviews showing the tentacle-free adaxial surface and tentacles along the leaf margins. (D) Partial leaf tip showing different size classes of stalked glands. (Scale bars: A, 100 µm; B, 500 µm; C and D, 1 mm.)  相似文献   
104.
Involvement of Rho kinase (ROCK) in sepsis-induced acute lung injury   总被引:1,自引:0,他引:1  
Indirect acute lung injury is associated with high morbidity and mortality. We investigated the link between Rho kinase (ROCK) activation and apoptotic cell death in sepsis induced acute lung injury. This hypothesis was tested by administering a specific, selective inhibitor of ROCK (Y-27632) to rats subjected to cecal ligation and puncture (CLP). Rats were randomly divided into 4 groups as; sham-operated, sham + Y-27632, CLP and CLP + Y-27632. Twenty-four hours later, each experiment was terminated and lungs analyzed. Histopathology was assessed by hematoxylin-eosin staining and the presence of apoptosis was evaluated through the TUNEL assay. Pulmonary activity of caspase 3 and ROCK 1 & 2 were measured by western blot. Interstitial edema, severely damaged pulmonary architecture with massive infiltration of the inflammatory cells and an increase in lung tissue TBARS levels as well as 3-NT to total tyrosine ratios were observed in untreated CLP animals. Pretreatment of animals with Y-27632, reduced lung injury in the CLP induced septic rats in each of these parameters of lung injury (p<0.05). Western immunoblot revealed active caspase cleavage and increased expression of active fragment of ROCK 1 & 2 in the CLP group. TUNEL assay showed an increase in percentage of apoptotic cells when comparing the CLP group with the CLP + Y-27632 group. These results suggest an important role of Rho kinase in sepsis induced lung injury by a mechanism that might be related to oxidative and/or nitrosative stress mediated caspase cleavage leading to apoptosis.  相似文献   
105.
A 63-year-old woman was admitted to our clinic with arthralgia, microhematuria and a pleural based solid mass in lower lobe basal segment of right lung seen in computerised tomogram of thorax. She was diagnosed as Wegener's granulomatosis by histopathological findings of right thoracotomy, wedge resection and decortication. The patient had positive antineutrophil cytoplasmic antibodies (c-ANCA) in serum and tissue specimens. Histopathologic examination of the renal biopsy specimen revealed the diagnosis of tubulointerstitial nephritis. We report this case because of the unusual histologic type of renal involvement by reviewing the literature.  相似文献   
106.
Dynamic precautions in the early diagnosis and treatment of hospital acquired pneumonias are necessary because of their high mortality. In these patients, invasive diagnostic approaches may be needed since clinical and radiological findings and other non-invasive approaches frequently fail to establish the diagnosis. Thirty eight patients were prospectively included in the study. Average age of patients was 45.5 +/- 16.4 years; 31 were males (81.6%) and 7 (18.4%) were females. Pneumonia was detected in 9 (23.7%) cases during the first five days and in 29 (76.3%) cases after the fifth day of admission to the hospital. Bronchoscopic interventions diagnostic purpose were carried out in 25 (65.8%) patients. The culture results were negative in 7 (18.4%) cases. While more than one pathogen was determined on the cultures of 16 (42.1%) patients only one pathogen was isolated in the cultures of 15 (39.4%) cases. The frequently isolated pathogen on cultures was Staphylococci (45.4%). Other pathogens were Enterobacter spp., Pseudomonas spp., Escherichia coli, Serratia and Streptococcus pneumoniae according to their frequency on cultures. High resistance rates to the third generation cephalosporins were determined. Eleven of 17 deaths in 38 pneumonia cases were attributable to pneumonia. As a conclusion, isolation of pathogen and antibiotic resistance should be determined in the cases with hospital acquired pneumonia. Invasive diagnostic interventions were not avoided when necessary. Although pro-BAL and PSB methods were expensive, their use in selected cases may prevent unnecessary antibiotic use and contribute to a decrease in mortality rate.  相似文献   
107.
Tuberculosis continues to be a significant cause of morbidity and mortality. Although tuberculosis usually attacks the lungs, other organs can also be affected, leading to extrapulmonary tuberculosis (EPT) or disseminated tuberculosis. This study retrospectively analysed the incidence, clinical sites and risk factors for EPT in 252 patients with EPT between 1 January 1991 and 30 June 2003. EPT was defined as clinical, laboratory, imaging, and/or histopathological evidence of mycobacterial infection in a site other than hilar lymph nodes or lung parenchyma. In our study group, tuberculous lymphadenitis (36.5%) was found to be the most common clinical presentation of EPT. 119 (47.2%) patients developed the severe form of EPT, according to the WHO report, and 133 (52.8%) patients developed the less severe form. A case history of pulmonary tuberculosis was found to be a risk factor for the development of EPT (p <0.05). The study showed that EPT is still a public health problem. These findings suggested that pulmonary tuberculosis may play a critical role in the development of EPT. 12-month therapy may be chosen in patients with EPT considering acceptable adverse effects without relapses.  相似文献   
108.
109.
Abstract

Background: Surface antigen CD38 which is a multifunctional protein with enzymatic and receptorial properties is involved in many processes of cell proliferation and activation. It is widely expressed within the hematopoetic system, and its expression is stimulated by proinflammatory cytokines. CD38-associated enzymatic activities in erythrocytes from cancer patients were investigated in this context.

Methods: Erythrocyte NAD glycohydrolase and ADP-ribosyl cyclase activities in normal individuals and cancer patients were compared and correlation of these activities to CEA values and anemia were determined. Changes in CD38-expression were followed by SDS-PAGE and Western blot analysis of erythrocyte membrane proteins.

Results: Erythrocyte NAD glycohydrolase and ADP-ribosyl cyclase activities were significantly increased in cancer, in parallel to enhancement of CD38 expression and in correlation with CEA values and anemia.

Conclusions: An increased expression of CD38 which may be due to action of proinflammatory cytokines produced in tumor–host reactions appears to account for the elevations in erythrocyte CD38-associated enzyme activities in cancer patients. The changes in these enzyme activities may provide a prognostic outlook in view of their apparently close correlation to tumor progressions.  相似文献   
110.
Pain originating from intramuscular (IM) injection should not be underestimated, because a painful injection might incite severe fear of injection, which may lead a patient to delay seeking medical help. The aim of this study was to determine the impact of two different IM methylprednisolone injection speeds on pain intensity and pain duration. A one-group quasiexperimental design was used to study 10-second versus 30-second injection durations. According to the formula for one sample using average values, 25 patients were recruited from a dermatology clinic. Data were collected using the “Patient Characteristics Form” and the visual analog scale (VAS). The mean difference in pain levels according to the VAS in the postinjection period was significantly higher with administration of IM methylprednisolone in 10 seconds compared with 30-second administration (VAS 1.9 vs. 1.3; p < .05). The severity of pain peaked at 0 minutes for both injection speeds, but the duration of pain was longer with 10-second injections. The data showed that at multiple time points after 10-second injections, men and patients >40 years old experienced greater pain severity. Pain severity after 30-second injections was greater for patients of normal or low weight who had completed higher levels of education. In conclusion, slow IM injection of steroids improves pain management.  相似文献   
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