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11.
Proliferative lesions of oviduct and uterus in CD-1 mice exposed prenatally to tamoxifen 总被引:1,自引:3,他引:1
Tamoxifen (TAM) is widely used as adjuvant breast cancer therapy after
surgery and as a chemopreventive agent in women of child-bearing age.
However, TAM therapy has been shown to result in an increased incidence of
endometrial carcinoma in women. The present study was designed to
investigate the effects of TAM (5 mg/kg and 7.5 mg/kg body wt) given i.g.
to pregnant CD-1 mice (1x/day, days 12 through 18 of gestation) on their
female offspring. Progressive proliferative hyperplasia of the oviduct was
frequently seen in TAM-exposed offspring, reaching 100% incidence by 52
weeks in both treatment groups. These females also developed progressive
proliferative uterine lesions, including moderate/severe cystic endometrial
hyperplasia (34-50%) and polypoid adenomas (27-30%) between 53 and 78
weeks. Deciduomas (15%) occurred at young ages (12 and 24 weeks) while
leiomyomas (14%), a malignant leiomyosarcoma, and ovarian granulosa cell
tumors (14%), were found between 72 and 78 weeks. Our findings thus suggest
a strong association between transplacental TAM and reproductive tract
abnormalities in female CD-1 mice.
相似文献
12.
Background. Klippel-Feil syndrome (KFS) is characterised by congenital vertebral fusion of the cervical spine and a wide spectrum of
associated anomalies. KFS has often been considered a sporadic syndrome. However, since the publication of the original KFS
classification early this century, a number of KFS families have indicated heterogeneity complicated by a broad range of variable
expression. Objective. The two major objectives of this study were (1) to identify differences and similarities in the postnatal appearance, morphology,
position and inheritance of vertebral fusions within and between KFS families and (2) to establish a new KFS classification
focussed on KFS aetiology. Materials and methods. Vertebral fusions were assessed via spinal radiography. Chromosomal karyotypes were performed using routine cytogenetics.
Results. The medical histories of three KFS families are presented. The postnatal time, position and appearance of vertebral fusions,
associated anomalies and mode of inheritance were different for the three KFS families. Four classes of KFS are described
in a comprehensive classification table that allays much of the uncertainty arising from KFS heterogeneity and variable expression.
Conclusion. We have described four different KFS classes (KF1–4) within a comprehensive classification that addresses KFS genetic heterogeneity.
The position of vertebral fusions in the cervical spine and their incidence within affected families are delineating features
of KFS.
Received: 10 October 1997 Accepted: 20 April 1998 相似文献
13.
Serving personnel of Armed Forces admitted with tuberculosis between Apr 1996–1999 were evaluated for co-infection of tuberculosis and HIV. Sixty (1.06%) of tuberculosis patients were found to be HIV positive. Initial test was done by spot kits and subsequently confirmed by ELISA on two different samples. Majority of the cases were in sexually active age group 48 (80%). Alcohol and smoking was associated in 80% cases. Thirty six (60%) were sputum smear positive for AFB. Twenty eight (46.7%) gave history of exposure to sex workers. Family members were not available for study. Sero prevalence of HIV in association with tuberculosis is less in Armed Forces compared to civil population.KEY WORDS: HIV, Seroprevalence, Tuberculosis 相似文献
14.
15.
ABSTRACT: BACKGROUND: High maternal mortality in India is a serious public health challenge. Demand side financing interventions have emerged as a strategy to promote access to emergency obstetric care. Two such state run programs, Janani Suraksha Yojana (JSY)and Chiranjeevi Yojana (CY), were designed and implemented to reduce financial access barriers that preclude women from obtaining emergency obstetric care. JSY, a conditional cash transfer, awards money directly to a woman who delivers in a public health facility. This will be studied in Madhya Pradesh province. CY, a voucher based program, empanels private obstetricians in Gujarat province, who are reimbursed by the government to perform deliveries of socioeconomically disadvantaged women. The programs have been in operation for the last seven years.Methods/designsThe study outlined in this protocol will assess and compare the influence of the two programs on various aspects of maternal health care including trends in program uptake, institutional delivery rates, maternal and neonatal outcomes, quality of care, experiences of service providers and users, and cost effectiveness. The study will collect primary data using a combination of qualitative and quantitative methods, including facility level questionnaires, observations, a population based survey, in-depth interviews, and focus group discussions. Primary data will be collected in three districts of each province. The research will take place at three levels: the state health departments, obstetric facilities in the districts and among recently delivered mothers in the community. DISCUSSION: The protocol is a comprehensive assessment of the performance and impact of the programs and an economic analysis. It will fill existing evidence gaps in the scientific literature including access and quality to services, utilization, coverage and impact. The implementation of the protocol will also generate evidence to facilitate decision making among policy makers and program managers who currently work with or are planning similar programs in different contexts. 相似文献
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17.
Yogesh Diwan Randhir S. Chauhan D.S. Dhiman Sanjiv Sharma Deepa Diwan 《Journal of the Anatomical Society of India》2013,62(2):120-124
AimsTo find out the normal pattern of hepatic veins in the North Indian population and to categorize them.MethodsThe present study was conducted on 100 patients whose spiral CT abdomen was performed for various medical conditions in the department of radiodiagnosis.ResultsFour categories were recognized. Category-1, when right hepatic vein drains independently into the inferior vena cava whereas middle and left hepatic veins join together to form a common trunk before draining into the inferior vena cava. It was observed in 74% patients. Category-2 was observed in 2% patients, where right & middle hepatic veins join to form a common trunk and left hepatic vein drain independently into the inferior vena cava. Category-3 was observed in 21% patients, where all the three major hepatic veins drain independently into the inferior vena cava. Category-4 was observed in 3% patients, where all the three major hepatic veins join together to form a common trunk before draining into the inferior vena cava.ConclusionsCategory-1 is the most common pattern of major hepatic vein drainage found in the North Indian population. The present study also concluded that single right, middle and left hepatic vein is the most common pattern of hepatic veins present in the North Indian population. Caudate lobe is drained by more than one vein in majority of North Indians. Also superomedial vein, right accessory vein and inferior right hepatic vein are the most common accessory veins present in the North Indian population. 相似文献
18.
19.
VK Viswanathan 《Gut microbes》2014,5(3):275-276
The robust expression of microbial pattern recognition receptors such as TLR4 and Nod2 in intestinal stem cells reflects an active communication dynamic between the host and the gut microbiota. A new study reveals that muramyl dipeptide, the bacterial cell wall peptidoglycan motif, activates Nod2 within crypt base columnar Lgr5-positive stem cells and promotes their survival. Apart from the immediate relevance to the growth of organoids for in vitro experiments, the study raises new questions about the molecular mechanisms whereby gut microbes influence intestinal physiology. 相似文献
20.
Meagan A. Barry Misha V. Koshelev Grace S. Sun Sarah J. Grekin Charles E. Stager A. Hafeez Diwan Carina A. Wasko Kristy O. Murray Laila Woc-Colburn 《The American journal of tropical medicine and hygiene》2014,91(2):345-347
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 (Patient Age, years/sex Lesion location; size; presence of satellite lesions (+/−) Diagnosis and pathogen Duration of disease before initiation of treatment Treatment course 1 38/F Proximal right posterior arm; 5 cm; (+) CL L. (V.) panamensis 3 months AmBisome (days 1–5, 14, 21) 2 46/M Distal left forearm; 2 lesions: 4 cm and 3 cm; (+) CL L. (V.) panamensis 2 months AmBisome (days 1–5, 14, 21); then itraconazole (daily, 30 days) 3 43/M Vertex of scalp, 8 more lesions on eyes, legs, and torso; 5 cm, other lesions 1 cm; (+) CL L. (V.) panamensis 2 weeks AmBisome (days 1–5); then pentostam (daily, 20 days) 4 43/F Left malar area; 1.5 cm; (+) CL L. (V.) panamensis 3 months AmBisome (days 1–5, 14)