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41.
The purpose of the present work was to characterize two new polymorphic microsatellite markers in the thyroglobulin gene. TGrI29 and TGrI30 repeats are located within introns 29 and 30, respectively. Genetic studies were carried out by using polymerase chain reaction (PCR) followed by denaturing polyacrilamide gel electrophoresis. TGrI29 exhibited clearly 4 distinguishable alleles ranging from 197 to 203 base pair (bp) in length and TGrI30 showed 8 alleles ranging from 502 to 542 bp. We characterized the two markers by determinating allele frequencies and measures of variation. The heterozygosities (HET) observed of TGrI29 and TGrI30 were 0.859 and 0.522, respectively. The polymorphism information contents (PIC) were 0.471 and 0.434, respectively. No significant differences from Hardy-Weinberg values were found for these two systems. The PCR products of each allele were cloned using the pGEM-T Easy vector and directly sequenced by Taq polymerase-based chain terminator method. Sequencing analysis indicated that both loci are complex repeats, TGrI29 containing two types of variable motifs (tc)n and (tg)n, and TGrI30 a tetra-nucleotide tandem units (atcc)n. In two TGrI29 alleles and one TGrI30 allele were found two different subtypes in each one, with the same molecular weights but different distribution of the tandem repeats. In conclusion, both microsatellites analyzed are highly informative polymorphic markers and can be used in linkage studies in families with congenital hypothyroidism or autoimmunity thyroid diseases.  相似文献   
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Based on a literature search undertaken to determine the impacts of past public health crises, and a systematic review of the effects of past economic crises on alcohol consumption, two main scenarios—with opposite predictions regarding the impact of the current COVID‐19 pandemic on the level and patterns of alcohol consumption—are introduced. The first scenario predicts an increase in consumption for some populations, particularly men, due to distress experienced as a result of the pandemic. A second scenario predicts the opposite outcome, a lowered level of consumption, based on the decreased physical and financial availability of alcohol. With the current restrictions on alcohol availability, it is postulated that, for the immediate future, the predominant scenario will likely be the second, while the distress experienced in the first may become more relevant in the medium‐ and longer‐term future. Monitoring consumption levels both during and after the COVID‐19 pandemic will be necessary to better understand the effects of COVID‐19 on different groups, as well as to distinguish them from those arising from existing alcohol control policies.  相似文献   
46.
The sensitivity and specificity of Rubascan (r) (RSC), a new latex agglutination test for rubella antibodies, was compared with those of the single radial hemolysis (SRH) and hemagglutination inhibition (HI) tests. We found RSC to have a sensitivity versus SRH and HI of 90-95% and 70-72%, respectively. RSC had a specificity versus SRH and HI of 97-100% and 96-100%, respectively. However, only 4/7 titer rises from cases of acute rubella or rubella vaccinations were clearly discernible in RSC. Moreover, only 2/10 anti-rubella IgG and IgM containing sera were RSC positive after protein A absorption although 10/10 were still HI positive. Additionally, the HI-positive IgM fractions from a sucrose density gradient centrifugation of an anti-rubella IgM containing serum were negative. We conclude that IgM reacts differently from IgG in RSC. We consider RSC a potentially useful reagent for determination of immunity in non-acute situations, and in non-pregnant persons like in pre-employment testing. This could be performed by relatively untrained personnel. On the other hand a rubella immunity test in pregnant women or in acute rubella should preferably be truly quantitative, in order to allow precise titer comparisons. In these cases, the interpretation of tests may require experience, and they should be performed at more specialized laboratories.  相似文献   
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48.

Background

Somatostatin acts through five receptor subtypes (SSTRs 1–5). We aimed to investigate SSTRs mRNA expression and protein distribution in whole rat embryos, with special emphasis on the pancreas.

Material and methods

Rat embryos were collected on embryonal days 10, 11, 12, 14, 15, 17, 19, 21, and at birth. Presence of SSTRs was investigated with RT-PCR techniques and immunohistochemistry.

Results

There was no SSTR5 mRNA expression in the whole rat embryos. All SSTR1–5 proteins were observed at embryonal day 10, but the localization varied between the different subtypes. From day 11 to birth SSTRs protein presence increased with time in major structures such as skin and cartilage. It remained similar over time in the heart and liver. In the fetal pancreas mRNA expression of SSTR2 and 4 was detected at day 14, and there was an increase up to birth. Only SSTR1 protein co-localized to a higher extent with the islet hormones studied. SSTR2 was present in all islet endocrine cells except for β-cells. In contrast, the immunostaining for SSTR3–4 was co-localized with insulin and PP, and, finally, SSTR5 with glucagon and pancreatic polypeptide. In mRNA isolated from whole rat embryos SSTR1-2 and SSTR4 expression showed a peak at day 14, while SSTR3 mRNA was not present until day 15.

Conclusion

The present data suggest a role for SSTRs during the development of the rat embryo. Subsequent functional studies may elucidate regulatory roles of specific SSTRs for the growth and differentiation of the pancreas as well as other organs.  相似文献   
49.
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   
50.
Influence of the hyrax expander screw position on stress distribution in the maxilla: A study with finite elements     
Letícia Chaves Fernandes  Robert Willer Farinazzo Vitral  Pedro Yoshito Noritomi  Carina Abrantes Schmitberger  Marcio José da Silva Campos 《American journal of orthodontics and dentofacial orthopedics》2019,155(1):80-87
  相似文献   
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