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41.
BACKGROUND: Although it is widely recognized that there are familial elements in the pathogenesis of hypertension, remarkably little is known about the influence of family history on response to specific antihypertensive agents. METHODS: This study was designed to address that issue by comparing the depressor response to lisinopril in a dose range of 10 to 40 mg in 74 patients enrolled as sibling pairs. Because all patients were treated with lisinopril, ambulatory blood pressure monitoring (ABPM), an objective measure not influenced by the investigators, was used to assess the primary blood pressure (BP) outcome variable. RESULTS: Diastolic BP was highly correlated between sibling pairs at baseline (r = 0.476; P < .03) and on treatment (r = 0.524; P = .0021). Ethnicity/race had a striking influence on lisinopril dose and response rate. Among African American patients, 23 of 28 reached the top dose of 40 mg/day, whereas only 14 of 36 Caucasian patients reached that dose level. Among Caucasians, 92% responded, and only 48% of African Americans. Responders were characterized by being younger and heavier, having significantly lower microalbuminuria at baseline, higher baseline renal plasma flow (RPF), and higher urinary kallikrein. CONCLUSION: Among Caucasians, the presence of a hypertensive sibling predicts a striking therapeutic response to angiotensin converting enzyme inhibition.  相似文献   
42.
Papillary thyroid carcinomas with lung metastases.   总被引:3,自引:0,他引:3  
BACKGROUND: Limited information is available on the presentation, treatment outcomes, and prognostic factors of papillary thyroid carcinoma with lung metastases. METHODS: This study retrospectively analyzed the data of 2003 patients with thyroid cancer who were treated and followed up at Chang Gung Memorial Hospital from January 1979 to December 2002. In total, 1516 papillary thyroid carcinomas were enrolled. One hundred two (6.7%) papillary thyroid carcinomas with lung metastases were followed including 57 women with mean age of 41.7 +/- 17.3 years and 45 men with mean age of 49.6 +/- 17.2 years. These patients included 52 patients with papillary thyroid carcinoma who presented with lung metastases at the time of diagnosis. The 102 cases of papillary thyroid carcinomas with lung metastases included 72 cases with lung metastases only, and 30 cases with other organ involvement. RESULTS: After mean follow-up periods of 8.8 +/- 0.6 years, 28 (27.5%) of the patients with lung metastasis died, while 6 improved to clinical stage I. The 5-, 10-, 15-, and 20-year survival rates in patients with papillary thyroid carcinoma without distant metastasis and in the lung metastases groups were 99.0%, 98.5%, 98.0%, 98.0%, and 91.3%, 75.0%, 64.0%, 51.2%, respectively. Comparing the Kaplan-Meier survival curves between the patients with papillary thyroid carcinomas with lung metastases only and those with multiorgan metastases demonstrates no statistically significant difference in mortality rates. However, age, gender, postoperative thyroglobulin (Tg) level and tumor size displayed statistically significant differences between the lung metastases and no distant metastasis groups. Fifty of the 102 patients with papillary thyroid carcinomas with lung metastases developed lung metastases during follow-up. Larger amounts of remnant thyroid tissues with higher Tg levels were noted in these patients compared to those without distant metastasis. CONCLUSIONS: The prognosis of patients with papillary thyroid carcinoma with lung metastases at time of diagnosis is the same as for those whose lung metastases are discovered later. Survival analysis demonstrates no difference between lung metastases and multiorgan metastases.  相似文献   
43.
Two pancreatic acinar cell carcinomas with distinctive morphologic features are described. Both tumors showed a variable combination of different histomorphologic patterns formed by tumor cells in different degrees of acinar differentiation. They caused diagnostic problems involving differential diagnosis from normal pancreas and from mixed acinar-endocrine tumor. The presence of mitosis, nuclear atypia, and tumor necrosis are helpful for recognizing its neoplastic nature, and the ultrastructural finding of zymogen-like but not neurosecretory granules prevented the misdiagnosis of a mixed acinar-endocrine tumor. Immunohistochemical studies revealed variable immunostaining patterns corresponding to different types of tumor cell present. Both tumors were found to be aneuploid by flow cytometric DNA study. Our study confirmed previous observations that pancreatic acinar cell carcinomas are highly malignant tumors in spite of the fact that they can differentiate into highly differentiated acinar cells.  相似文献   
44.
Ticlopidine-associated aplastic anemia   总被引:2,自引:0,他引:2  
 Serious hematologic complications associated with ticlopidine have been reported, including aplastic anemia. We report here an additional case of fatal aplastic anemia due to ticlopidine. A 66-year-old male patient developed fever and pancytopenia 2 months after ticlopidine was started. Despite the administration of granulocyte colony-stimulating factor (G-CSF) and broad-spectrum antibiotics, as well as aggressive red cell and platelet transfusions, the patient died 16 days after admission due to septic shock. Eighteen other cases of ticlopidine-induced aplastic anemia published in the English literature are also reviewed and presented here. Eight of the total 19 patients (including the one reported here) have died, mostly due to infection. Of the seven who received supportive treatment only, four had spontaneous recovery. Nine cases were treated with G-CSF or granulocyte-macrophage colony-stimulating factor (GM-CSF), and response was observed in only four of them. Several other cases were treated with high-dose corticosteroids or androgens; however, it was not possible to evaluate the efficacy of these treatments because of the limited number of cases. In the absence of satisfactory treatment for ticlopidine-induced aplastic anemia at present, it may be reasonable to try antilymphocyte globulin or cyclosporine. Also, great efforts should be made in the prevention and management of infection accompanying this disease. Received: 2 November 1997 / Accepted: 12 January 1998  相似文献   
45.
AJ  Fay  T  McMahon  C  Im  C  Bair-Marshall  KJ  Niesner  H  Li  A  Nelson  SM  Voglmaier  Y-H  Fu  LJ  Ptáček 《Neurogenetics》2021,22(3):171-185

Paroxysmal kinesigenic dyskinesia is an episodic movement disorder caused by dominant mutations in the proline-rich transmembrane protein PRRT2, with onset in childhood and typically with improvement or resolution by middle age. Mutations in the same gene may also cause benign infantile seizures, which begin in the first year of life and typically remit by the age of 2 years. Many details of PRRT2 function at the synapse, and the effects of mutations on neuronal excitability in the pathophysiology of epilepsy and dyskinesia, have emerged through the work of several groups over the last decade. However, the age dependence of the phenotypes has not been explored in detail in transgenic models. Here, we report our findings in heterozygous and homozygous Prrt2 knockout mice that recapitulate the age dependence of dyskinesia seen in the human disease. We show that Prrt2 deletion reduces the levels of synaptic proteins in a dose-dependent manner that is most pronounced at postnatal day 5 (P5), attenuates at P60, and disappears by P180. In a test for foot slippage while crossing a balance beam, transient loss of coordination was most pronounced at P60 and less prominent at age extremes. Slower traverse time was noted in homozygous knockout mice only, consistent with the ataxia seen in rare individuals with biallelic loss of function mutations in Prrt2. We thus identify three age-dependent phenotypic windows in the mouse model, which recapitulate the pattern seen in humans with PRRT2-related diseases.

  相似文献   
46.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative viral pathogen of coronavirus disease 2019 (COVID-19), appears to have various clinical presentations and may result in severe respiratory failure. The global SARS-CoV-2-associated viral pneumonia pandemic was first reported in December 2019 in China. Based on known pharmacological mechanisms, many therapeutic drugs have been repurposed to target SARS-CoV-2. Among these drugs, remdesivir appears to be the currently most promising according to several clinical trials and reports of compassionate use. In this mini-review, we summarize the current evidence on the efficacy and challenges of remdesivir for the treatment of coronavirus disease 2019 (COVID-19).  相似文献   
47.
An antagonist analog of GnRH, (Ac-delta 3-Pro1,p-F-D-Phe2,D-Trp3,6)GnRH (4F-antagonist), was administered to normal women and women with hypergonadotropic hypogonadism. Serum FSH levels were determined by both the granulosa cell aromatase bioassay and RIA. The constant infusion of 4F-antagonist (30 micrograms/kg.h) to the four hypogonadal women resulted in a more pronounced decline in bioactive FSH (62%) than in immunoreactive FSH levels (30%), and the FSH bioactive to immunoreactive ratio decreased significantly (P less than 0.05). Infusion of 4F-antagonist in normal women in the midfollicular phase revealed a similar pattern of suppression of bioactive (64%) and immunoreactive FSH (29%). When 4F-antagonist was administered sc at a dose of 80 micrograms/kg twice daily for 3 days to normal women in the midfollicular phase of their cycles, the bioactive FSH response was biphasic, with the maximal decrease on the second day, followed by return to basal levels on the third day. Correspondingly, there was a precipitous decline in serum estradiol (apparent demise of the dominant follicle), followed by a progressive rise in estradiol levels. Thus, in contrast to immunoreactive FSH levels, bioactive FSH more clearly reflects the biological action of FSH on the follicle in response to GnRH antagonist administration in women. The disparity in the quantitative decline between serum bioactive and immunoreactive FSH levels after presumed blockade of the GnRH receptor may reflect the microheterogeneity of the FSH molecule and suggests that alterations in the biological activity of secreted FSH may be GnRH dependent.  相似文献   
48.
49.
Sudo S  Kuwabara Y  Park JI  Hsu SY  Hsueh AJ 《Endocrinology》2005,146(8):3596-3604
Glycoprotein hormones play important roles in thyroid and gonadal function in vertebrates. The glycoprotein hormone alpha-subunit forms heterodimers with different beta-subunits to activate TSH or gonadotropin (LH and FSH) receptors. Recent genomic analyses allowed the identification of another alpha-subunit, GPA2, and another beta-subunit, GPB5, in human, capable of forming heterodimers to activate TSH receptors. Based on comparative genomic searches, we isolated the fly orthologs for human GPA2 and GPB5, each consisting of 10 cysteine residues likely involved in cystine-knot formation. RT-PCR analyses in Drosophila melanogaster demonstrated the expression of GPA2 and GPB5 at different developmental stages. Immunoblot analyses further showed that fly GPA2 and GPB5 subunit proteins are of approximately 16 kDa, and coexpression of these subunits yielded heterodimers. Purified recombinant fly GPA2/GPB5 heterodimers were found to be glycoproteins with N-linked glycosylated alpha-subunits and nonglycosylated beta-subunits, capable of stimulating cAMP production mediated by fly orphan receptor DLGR1 but not DLGR2. Although the fly GPA2/GPB5 heterodimers did not activate human TSH or gonadotropin receptors, chimeric fly GPA2/human GPB5 heterodimers stimulated human TSH receptors. These findings indicated that fly GPA2/GPB5 is a ligand for DLGR1, thus showing the ancient origin of this glycoprotein hormone-seven transmembrane receptor-G protein signaling system. The fly GPA2 also could form heterodimers with human GPB5 to activate human TSH receptors, indicating the evolutionary conservation of these genes and suggesting that the GPA2 subunit may serve as a scaffold for the beta-subunit to activate downstream G protein-mediated signaling.  相似文献   
50.
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