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1.
Halipegus dubius Klein, 1905 is redescribed and illustrated from a Brazilian frog Leptodactylus ocellatus. The type-material of Halipegus genarchella (Travassos, Artigas & Pereira, 1928) and Halipegus parva (Travassos, Artigas & Pereira, 1928) are redescribed with original figures. New synonyms are proposed: Halipegus salmini Yamaguti, 1958 is considered a synonym of H. genarchella, H. tropicus (Manter, 1936) sensu Kloss (1966) of H. parva and Genarchella lenti Fábio, 1984 of H. overstreeti (Brooks, Mayes & Thorson, 1979) n. comb.  相似文献   
2.
Ectopic ACTH syndrome   总被引:2,自引:0,他引:2  
Ectopic ACTH syndrome represents a cancer-induced amplification of a property [proopiomelanocortin (POMC) peptides production] normally present in the cells from which the cancer originated but with aberrant posttranslational processing of POMC resulting in a greatly elevated secretion of ACTH precursors. The classic ectopic ACTH-producing tumors described in the 1960s were highly malignant but more recently slowly growing tumors such as carcinoids are reported with increasing frequency. Clinical features of patients with ectopic ACTH were analyzed, including biochemical abnormalities, plasma ACTH, cortisol and urinary steroids. Dynamic tests such as high-dose dexamethasone suppression, metyrapone and ovine-CRH (oCRH) stimulation were explored, as well as inferior petrosal sinus ACTH sampling before and after oCRH. Among the tumor markers examined, elevation of ACTH precursors was uniformly present followed by increased output of calcitonin, gut hormones, oncofetal and placental hormones in decreasing order. Since more than 90% of ectopic ACTH tumors are neuroendocrine in nature exhibiting APUD characteristics, their 2 markers, neuron-specific enolase and chromogranins are very useful. The imaging procedures for localization of the tumor ranged from chest X-rays to computed tomography and magnetic resonance of the chest and abdomen. Abdominal ultrasonography was also useful. Finally somatostatin receptor scintigraphy permitted demonstration of unrecognized tumors and/or metastases, even when the tumors were occult. The ACTH content, immunostaining for APUD markers and altered POMC processing were evaluated in ectopic tumors and/or metastases. Occult ectopic ACTH syndrome of more than 4–6 months of symptoms without the emergence of an obvious source was reviewed. Since the tumors are often clinically and biochemically undistinguishable from pituitary-dependent Cushing's disease, inferior petrosal sinus sampling for ACTH after oCRH stimulation established the diagnosis in over 90% of the cases. 60% of the occult tumors were thoracic carcinoids (3/4 bronchial carcinoids), followed by small cell lung cancer and pancreatic neuroendocrine tumors. In 12% the primary etiology was not detected. The rare syndrome of ectopic CRH syndrome (6 published cases) leading to excessive stimulation of the pituitary which became hyperplastic and secreted excessive amounts of ACTH is discussed. Finally, the 12 published cases and 1 unreported patient with ectopic CRH-ACTH tumors were reviewed, the majority being metastatic small cell lung carcinomas, bronchial and thymic carcinoids.  相似文献   
3.
A polyvalent conjugate forLegionella pneumophila, the Legionnaires’ disease bacterium, was prepared by combining monospecific antibodies for the four recognized serogroups ofL. pneumophila. Pure cultures ofL. pneumophila and other bacteria representing 18 genera and 50 species of heterologous organisms were used in evaluating the reagent. A total of 358 specimens from patients suspected of having Legionnaires’ disease also were tested. The results show the practicality and advantages of using a polyvalentL. pneumophila conjugate for screening clinical specimens.  相似文献   
4.
Grafting an allogeneic neonatal thymus to a congenitally athymic adult nude mouse allows a sufficient generation of φ-positive lymphocytes to bring their relative and absolute numbers close to the values found in normal mice. However, the T-cell characteristic reactivities of thymus-grafted nudes persistently remain low, especially the responsiveness of lymphoid cell suspensions to T-cell mitogens. In a series of thymus-grafted nudes, significant numbers of thymus donor type lymphocytes were found to persist for long periods of time within the grafted thymus, but their persistence could not be directly correlated with the acceptance of skin of same strain origin as the thymus or with responsiveness to mitogens.  相似文献   
5.

Background

The International Study on Asthma and Allergies in Childhood (ISAAC) reported a prevalence of asthma symptoms in 17 centers in nine Latin American countries that was similar to prevalence rates reported in non-tropical countries. It has been proposed that the continuous exposure to infectious diseases in rural populations residing in tropical areas leads to a relatively low prevalence of asthma symptoms. As almost a quarter of Latin American people live in rural tropical areas, the encountered high prevalence of asthma symptoms is remarkable. Wood smoke exposure and environmental tobacco smoke have been identified as possible risk factors for having asthma symptoms.

Methods

We performed a cross-sectional observational study from June 1, 2012 to September 30, 2012 in which we interviewed parents and guardians of Warao Amerindian children from Venezuela. Asthma symptoms were defined according to the ISAAC definition as self-reported wheezing in the last 12 months. The associations between wood smoke exposure and environmental tobacco smoke and the prevalence of asthma symptoms were calculated by means of univariate and multivariable logistic regression analyses.

Results

We included 630 children between two and ten years of age. Asthma symptoms were recorded in 164 of these children (26%). The prevalence of asthma symptoms was associated with the cooking method. Children exposed to the smoke produced by cooking on open wood fires were at higher risk of having asthma symptoms compared to children exposed to cooking with gas (AOR 2.12, 95% CI 1.18 - 3.84). Four percent of the children lived in a household where more than ten cigarettes were smoked per day and they had a higher risk of having asthma symptoms compared to children who were not exposed to cigarette smoke (AOR 2.69, 95% CI 1.11 - 6.48).

Conclusion

Our findings suggest that children living in rural settings in a household where wood is used for cooking or where more than ten cigarettes are smoked daily have a higher risk of having asthma symptoms.  相似文献   
6.

Background

Warao Amerindians, who inhabit the Orinoco Delta, are the second largest indigenous group in Venezuela.  High Warao general mortality rates were mentioned in a limited study 21 years ago. However, there have been no comprehensive studies addressing child survival across the entire population.

Objectives

To determine the Child Survival-Index (CSI) (ratio: still-living children/total-live births) in the Warao population, the principal causes of childhood death and the socio-demographic factors associated with childhood deaths.

Methods

We conducted a cross-sectional epidemiological survey of 688 women from 97 communities in 7 different subregions of the Orinoco Delta. Data collected included socio-demographic characteristics and the reproductive history of each woman surveyed. The multidimensional poverty index (MPI) was used to classify the households as deprived across the three dimensions of the Human Development Index. Multivariable linear regression and Generalized Linear Model Procedures were used to identify socioeconomic and environmental characteristics statistically associated with the CSI.

Findings

The average CSI was 73.8% ±26. The two most common causes of death were gastroenteritis/diarrhea (63%) and acute respiratory tract Infection/pneumonia (18%).  Deaths in children under five years accounted for 97.3% of childhood deaths, with 54% occurring in the neonatal period or first year of life.  Most of the women (95.5%) were classified as multidimensionally poor.  The general MPI in the sample was 0.56.   CSI was negatively correlated with MPI, maternal age, residence in a traditional dwelling and profession of the head of household other than nurse or teacher.

Conclusions

The Warao have a low CSI which is correlated with MPI and maternal age.  Infectious diseases are responsible for 85% of childhood deaths.  The low socioeconomic development, lack of infrastructure and geographic and cultural isolation suggest that an integrated approach is urgently needed to improve the child survival and overall health of the Warao Amerindians.   相似文献   
7.
Abnormal methylation is related to cancer development. Since DNMT3B is an enzyme that modulates genomic methylation, we hypothesized that genetic variants of the promoter DNMT3B may be associated with an increased risk of developing cervical cancer. Our aim was to investigate the association between ?579GT and 46359CT polymorphisms of DNMT3B and cervical cancer, high-grade squamous intraepithelial lesions (HSIL), and low-grade squamous intraepithelial lesions (LSIL). Samples from 200 healthy women and 130 women with squamous intraepithelial lesions (70 with cervical cancer, 30 with HSIL, and 30 with LSIL) were analyzed. Polymorphism genotyping was performed using PCR and restriction fragment length polymorphism. The ?579GT polymorphism was not associated with cervical cancer, HSIL, or LSIL. The CT genotype of 46359CT polymorphism was significantly associated with cervical cancer risk (OR 8.75, CI 1.27–374.1), whereas the TT genotype was associated with a significantly decreased risk of HSIL (OR 0.66, CI 0.01–0.32) and LSIL (OR 0.11, CI 0.026–0.45). Our results suggest that genotyping the 46359CT polymorphism in DNMT3B may help identify women who are genetically susceptible to cervical cancer development. Additional studies with larger sample sizes are necessary to confirm our findings.  相似文献   
8.

Background

Nannizzia nana is a zoophilic dermatophyte that affects animals like pigs, boars and, exceptionally, humans, in whom it causes tinea capitis, as well as tinea corporis and onychomycosis.

Case report

Case 1. A previously healthy 8 year-old boy presented to our clinic with a 1-month evolution dermatosis that affected scalp, developing a pseudoalopecic tumor lesion with abundant seropurulent material. The patient had worked in a pig farm. Case 2. A previously healthy 6 year-old girl, sister of the aforementioned child, presented to our clinic with a dermatosis characterized by multiple erythematous-scaly plaques that affected her face, trunk and arms. N. nana was the fungus isolated on culture in both cases. The children were treated with oral griseofulvin and topical ketoconazole that led to clinical and mycological cures.

Conclusions

N. nana dermatophytosis, although being rare in humans, can be treated as other cases of dermatophytosis.  相似文献   
9.
10.
OBJECTIVE: To establish the cut-off values of GH measured by immunofluorometric assay, a more sensitive and specific assay, in normal prepubertal children and compare their values with those of proven GH-deficient patients. METHODS: 30 normal children (20 males) and 26 patients with known causes of GH deficiency were submitted to the clonidine test and their GH values were compared. A powdered clonidine tablet (0.1 mg/m(2)) was given orally and blood samples for GH measurements were drawn at times -30, 0, 60, 90 and 120 min. RESULTS: GH peak values presented a wide variation ranging from 1.7 to 25 micro g/l (mean +/- SD = 12.87 +/- 5.8 micro g/l) in the normal group. The cut-off values for the 5th and 10th percentiles of the distribution curve were 3.3 and 5.5 micro g/l, respectively. In the GH deficiency group, maximum GH levels after clonidine stimulation ranged from <0.1 to 2.1 micro g/l (0.56 +/- 0.58 micro g/l). CONCLUSIONS: The cut-off values obtained with the immunofluorometric method are lower than the ones obtained by radioimmunoassay. We suggest a cut-off value of 3.3 micro g/l (5th percentile) that ensures 100% of sensitivity along with 93% of specificity to exclude the diagnosis of GH deficiency when using this immunofluorometric method.  相似文献   
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