Temporal trends in infective endocarditis: a population-based study in Olmsted County, Minnesota

Context  Limited data exist regarding population-based epidemiologic changes in incidence of infective endocarditis (IE). Objective  To evaluate temporal trends in the incidence and clinical characteristics of IE. Design, Setting, and Patients  Population-based survey using the resources of the Rochester Epidemiology Project of Olmsted County, Minnesota. One hundred seven IE episodes occurred in 102 Olmsted County residents between 1970 and 2000. The modified Duke criteria were used to validate the diagnosis of definite or possible IE. Main Outcome Measures  Incidence of IE, proportion of patients with underlying heart disease, and causative microorganisms and clinical characteristics. Results  Age- and sex-adjusted incidence of IE ranged from 5.0 to 7.0 cases per 100 000 person-years during the study period and did not change significantly over time (P = .42 for trend). Infective endocarditis caused by viridans group streptococci was the most common organism-specific subgroup, with an annual adjusted incidence of 1.7 to 3.5 cases per 100 000; in comparison, IE due to Staphylococcus aureus had an annual adjusted incidence of 1.0 to 2.2 cases per 100 000. No time trend was detected for either pathogen group (P = .63 and P = .66, respectively). An increasing temporal trend was observed in the proportions of prosthetic valve IE cases (P = .09). Among people with underlying heart disease, there was an increasing temporal trend in mitral valve prolapse (P = .04) and a decreasing trend in rheumatic heart disease (P = .08). However, the absolute numbers were small. There was no time trend in rates of valve surgery or 6-month mortality during the study period (P = .97 and P = .59, respectively). Conclusions  In this community-based temporal trend study, we found no substantial change in the incidence of IE over the past 3 decades. Viridans group streptococci continue to outnumber S aureus as the most common causative organisms of IE in this population.      

A Multifactorial Analysis of Melanoma: III. Prognostic Factors in Melanoma Patients with Lymph Node Metastases (Stage II)

Twelve prognostic features of melanoma were examined in a series of 185 patients with nodal metastases (Stage II), who underwent surgical treatment at our institution during the past 20 years. Forty-four per cent of the patients presented with synchronous nodal metastases (substage IIA), 44% of the patients had delayed nodal metastases (substage IIB), and 12% of the patients had nodal metastases from an unknown primary site (substage IIC). The patients with IIB (delayed) metastases had a better overall survival rate than patients with IIA (synchronous) metastases, when calculated from the time of diagnosis. These differences could be explained on the basis of tumor burden at the time of initial diagnosis (microscopic for IIB patients versus macroscopic for IIA patients). Once nodal metastases became evident in IIB patients, their survival rates were the same as for substage IIA patients, when calculated from the onset of nodal metastases. The survival rates for both subgroups was 28% at five years and 15% for ten years. Substage IIC patients (unknown 1° site) had better five-year survival rates (39%), but the sample size was small and the differences were not statistically significant. A multifactorial analysis was used to identify the dominant prognostic variables from among 12 clinical and pathologic parameters. Only two factors were found to independently influence survival rates: 1) the number of metastatic nodes (p = 0.005), and the presence or absence of ulceration (p = 0.0019). Additional factors considered that had either indirect or no influence on survival rates (p > 0.10) were: anatomic location, age, sex, remission duration, substage of disease, tumor thickness, level of invasion, pigmentation, and lymphocyte infiltration. All combinations of nodal metastases were analyzed from survival differences. The combination that showed the greatest differences was one versus two to four versus more than four nodes. Their five-year survival rates were 58%, 27% and 10%, respectively (p < 0.001). Ulceration of the primary cutaneous melanoma was associated with a <15% five-year survival rate, while nonulcerative melanomas had a 30% five-year survival rate (p < 0.001). The combination of ulceration and multiple metastatic nodes had a profound adverse effect on survival rates. While tumor thickness was the most important factor in predicting the risk of nodal metastases in Stage I patients (p < 10^-8), it had no predictive value on the patient's clinical course once nodal metastases had occurred (p = 0.507). The number of metastatic nodes and the presence of ulceration are important factors to account for when comparing surgical results, and when analyzing the efficacy of adjunctive systemic treatments.     

Engrafted bone marrow-derived flk-(1+) mesenchymal stem cells regenerate skin tissue

Stem cell plasticity has created great interest because of its potential therapeutic application in degenerative or inherited diseases. Transplantation of bone marrow-derived stem cells was shown to give rise to cells of muscle, liver, nerve, endothelium, epithelium, and so on. But there are still disputes about stem cell plasticity, especially concerning the contribution of bone marrow-derived cells to skin cells. In this study, CM-DiI fluorescence-labeled Flk-(1+) bone marrow mesenchymal stem cells (bMSCs) of BALB/c mice (H-2Kd, white) were transplanted into lethally irradiated C57BL/6 mice (H-2Kb, black). By fluorescence tracing, we found that donor cells could migrate and take residency at the skin, which was confirmed by Y chromosome-specific PCR and Southern blot. The recipient mice grew white hairs about 40 days later and white hairs could spread over the body. Immunochemistry staining and RT-PCR demonstrated that skin tissue within the white hair regions was largely composed of donor-derived H-2Kd cells, including stem cells and committed cells. Furthermore, most skin cells cultured from white hair skin originated from the donor. Thus, our findings provide direct evidence that bone marrow-derived cells can give rise to functional skin cells and regenerate skin tissue. These may have important scientific implications in stem cell biology and transplantation therapy for skin tissue injury.     

High serum leptin levels in depressive disorders with atypical features

Leptin is thought to be related to vegetative symptoms of depression such as alterations in food intake and weight. Fifty-seven drug-free patients and 26 healthy controls were enrolled in this study. We have found that the serum leptin levels were higher in patients with atypical depressive disorder than in controls, but not in patients with non-atypical depressive disorder, however, body mass index, age, and gender were not significantly different between these groups. Probably, these findings seem to be associated with some features of the atypical depressive disorders such as weight gain, a result of hyperphagia.     

Incidence of childhood brain tumors in Syria (1993-2002)

OBJECTIVE: To determine whether the incidence and location of childhood CNS tumors in Syria follows the same pattern described in Western and Far Eastern countries. PATIENTS AND METHODS: We analyzed the data compiled from 367 children with brain tumors operated on in our Department of Neurosurgery between 1993 and mid-2002. We excluded all vascular and metastatic lesions and adopted the latest WHO classification in grouping all glial tumors. RESULTS: We found that 47% of brain tumors were located in the supratentorial, and 53% in the infratentorial region. The ratio of male to female occurrence was 1:1.2 (52% males, 48% females). For lesions in the supratentorial space, the distribution was 56% males and 44% females, while in the posterior fossa, the distribution was 61% males and 39% females. Low-grade tumors (WHO I/II) constituted 53.5% of all lesions, and the rest were high grade tumors (WHO III/IV) 46.5%.The most common tumor found in our childhood population was medulloblastoma (27.5%), followed by astrocytoma (25.8%), then craniopharyngioma (14.1%). The most common tumor in the posterior fossa was medulloblastoma (53.5%), followed by astrocytoma (22.5%), then ependymoma (17%). The most common tumors in the supratentorial space were astrocytoma and craniopharyngioma. CONCLUSIONS: In our patient population, the incidence and distribution of CNS tumors were somehow different than those reported by authors from the Western and Far Eastern countries. Whether these results are unique to Syria, or reflect a regional difference in the disease distribution between the Middle East region and the rest of the world, remains to be determined.     

Helminth regulation of host IL-4Ralpha/Stat6 signaling: mechanism underlying NOS-2 inhibition by Trichinella spiralis

Gastrointestinal nematode infection is known to alter host T cell activation and has been used to study immune and inflammatory reactions in which nitric oxide (NO) is a versatile player. We previously demonstrated that Trichinella spiralis infection inhibits host inducible NO synthase (NOS-2) expression. We now demonstrate that (i) an IL-4 receptor alpha-subunit (IL-4Ralpha)/Stat6-dependent but T cell-independent pathway is the key for the nematode-induced host NOS-2 inhibition; (ii) endogenous IL-4 and IL-13, the only known IL-4Ralpha ligands, are not required for activating the pathway; and (iii) treatment of RAW264.7 cells with parasite-cultured medium inhibits NOS-2 expression but not cyclooxygenase 2 expression. We propose that a yet-unidentified substance is released by the nematode during the host-parasite interaction.     

Maxillary sinus disease of odontogenic origin

Odontogenic sinusitis is a well-recognized condition and accounts for approximately 10% to 12% of cases of maxillary sinusitis. An odontogenic source should be considered in patients with symptoms of maxillary sinusitis who give a history positive for odontogenic infection or dentoalveolar surgery or who are resistant to standard sinusitis therapy. Diagnosis usually requires a thorough dental and clinical evaluation with appropriate radiographs. Common causes of odontogenic sinusitis include dental abscesses and periodontal disease perforating the Schneidarian membrane, sinus perforations during tooth extraction, or irritation and secondary infection caused by intra-antral foreign bodies. The typical odontogenic infection is now considered to be a mixed aerobic-anaerobic infection, with the latter outnumbering the aerobic species involved. Most common organisms include anaerobic streptococci, Bacteroides, Proteus, and Coliform bacilli. Typical treatment of atraumatic odontogenic sinusitis is a 3- to 4- week trial of antibiotic therapy with adequate oral and sinus flora coverage. When indicated, surgical removal of the offending odontogenic foreign body (primary or delayed) or treatment of the odontogenic pathologic conditions combined with medical therapy is usually sufficient to cause resolution of symptoms. If an oroantral communication is suspected, prompt surgical management is recommended to reduce the likelihood of causing chronic sinus disease.