RESUMO
Few studies have focused on broad scale biogeographic patterns of ammonia oxidizers in coastal systems, yet understanding the processes that govern them is paramount to understanding the mechanisms that drive biodiversity, and ultimately impact ecosystem processes. Here we present a meta-analysis of 16 years of data of ammonia oxidizer abundance, diversity, and activity in New England (NE) salt marshes and 5 years of data from marshes in the Gulf of Mexico (GoM). Potential nitrification rates were more than 80x higher in GoM compared to NE marshes. However, nitrifier abundances varied between regions, with ammonia-oxidizing archaea (AOA) and comammox bacteria significantly greater in GoM, while ammonia-oxidizing bacteria (AOB) were more than 20x higher in NE than GoM. Total bacterial 16S rRNA genes were also significantly greater in GoM marshes. Correlation analyses of rates and abundance suggest that AOA and comammox are more important in GoM marshes, whereas AOB are more important in NE marshes. Furthermore, ratios of nitrifiers to total bacteria in NE were as much as 80x higher than in the GoM, suggesting differences in the relative importance of nitrifiers between these systems. Communities of AOA and AOB were also significantly different between the two regions, based on amoA sequences and DNA fingerprints (terminal restriction fragment length polymorphism). Differences in rates and abundances may be due to differences in salinity, temperature, and N loading between the regions, and suggest significantly different N cycling dynamics in GoM and NE marshes that are likely driven by strong environmental differences between the regions.
RESUMO
Human T-cell lymphotropic virus type I (HTLV-I) is endemic in the Caribbean basin and in Japan. HTLV-II, a closely related virus, is endemic in several groups of native Americans, including Panamanian Guaymi. In Panama, a nationwide HTLV-I/II seroprevalence of 1-2% has been reported. We evaluated the frequency of HTLV-I/II infection in patients with neurologic diseases admitted to state tertiary hospitals in Panama City between 1985 and 1990. Nineteen of 322 patients with eligible diagnoses had antibodies to HTLV-I/II, 17 with HTLV-I and 2 with HTLV-II. HTLV-I was associated with spastic paraparesis (13 of 23, 56.5% versus 4 of 299, 1.3%, p < 0.001) and with cerebellar syndrome (2 of 13, 15.4%) and multiple sclerosis (2 of 54, 3.7%) (p < 0.05 for both diseases compared with subject with none of these diagnoses). The two HTLV-I infected patients with cerebellar syndrome later developed spastic paraparesis. HTLV-II infection was noted in one patient with cerebellar syndrome and one with amyotrophic lateral sclerosis. All patients with other diagnoses were seronegative. Among patients with spastic paraparesis, HTLV-I-infected patients were clinically indistinguishable from seronegative subjects. There is apparently an overlapping clinical spectrum of neurologic diseases associated with HTLV-I and HTLV-II infection.
Assuntos
Infecções por HTLV-I/epidemiologia , Infecções por HTLV-II/epidemiologia , Doenças do Sistema Nervoso/epidemiologia , Adolescente , Adulto , Idoso , Doenças Cerebelares/complicações , Doenças Cerebelares/epidemiologia , DNA Viral/análise , Feminino , Anticorpos Anti-HTLV-I/análise , Infecções por HTLV-I/complicações , Anticorpos Anti-HTLV-II/análise , Infecções por HTLV-II/complicações , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/genética , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Esclerose Múltipla/epidemiologia , Doenças do Sistema Nervoso/complicações , Panamá/epidemiologia , Paraparesia Espástica Tropical/complicações , Paraparesia Espástica Tropical/epidemiologia , Reação em Cadeia da Polimerase , Prevalência , SíndromeRESUMO
Renal failure in diabeties mellitus is becoming the commonest cause of end-stage renal disease (ERSD) in developed and developing countries. While ERSD occurs in about 35 percent of patients with insulin-dependent diabetes mellitus (IDDM), it occurs generally in about 15-60 percent with non-insulin-dependent diabetes mellitus (NIDDM), depending on ethnicity. Since most of the diabetes are NIDDM, it follows that most of these patients developing renal failure and requiring dialysis are NIDDM. When significant proteinuria begins, usually after about 15-20 years of NIDDM or IDDM, renal function will fall steadily and the patient will require dialysis in 3-5 years or sooner. The proteinuric patients also have a 20-40-fold increase in cardiovascular mortality. About one-quarter of the patients who have negative routine urinary protein dipstick tests will have sub-clinical amounts of urinary albumin (30-300 mg/24 hr), so-called microalbuminuria (MA). This has recently been correlated with a very high incidence of microvascular disease. This MA predicts about a 20-fold chance of the patient developing clinical proteinuria and a high chance of ERSD. The accumulated evidence suggests that a common pathogenic mechanism may exist for microalbuminuria, diabetic nephropathy, atherosclerosis and obesity. Obesity seems to be related to all of these factors in that it has been associated with insulin resistance, hypertension and so dium retention, atherosclerosis and hyperlipidaemia (HL). NIDDM patients are almost always obese and they always have insulin resistance, which improves with weight loss. There is growing clinical evidence of hereditary influence in NIDDM, HL, and hypertension with the clustering of diabetic nephropathy in these high-risk families. These data show that genetic factors may well play a major role, and it is therefore understandable that we may have difficulty in altering the already genetically charted course of proteinuria, hypertension, HL, and NIDDM (AU)
Assuntos
Humanos , Nefropatias Diabéticas , Diabetes Mellitus , Insuficiência Renal Crônica , Diabetes Mellitus Tipo 1 , Proteinúria , Diálise , Doenças Vasculares , Diabetes Mellitus , Resistência à Insulina , Hipertensão , Arteriosclerose , Hiperlipidemias , Doenças Genéticas Inatas , Genética , JamaicaRESUMO
We examined the association between clinical status and exposure to tobacco smoke in 44 patients homozygous for the F508 cystic fibrosis mutation. Heavy exposure to tobacco smoke was significantly associated with lower Shwachman scores, poorer results of pulmonary function tests, and a fivefold increase in the number of pulmonary-related hospitalizations during the previous year.
Assuntos
Deleção Cromossômica , Fibrose Cística/fisiopatologia , Homozigoto , Poluição por Fumaça de Tabaco/efeitos adversos , Adolescente , Adulto , Criança , Pré-Escolar , Fibrose Cística/genética , Feminino , Volume Expiratório Forçado , Humanos , Lactente , Masculino , Capacidade VitalRESUMO
HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is endemic in the Caribbean basin and Japan. Because of the close proximity of the United States to the Caribbean and the presence of HTLV-I-seropositive persons in the United States, we sought reports of patients who were HTLV-I seropositive and had a slowly progressive myelopathy. Over a 2-year period, there were 25 patients reported, 19 of whom were black and 12 of whom had been born in the United States. All patients except two had become symptomatic while living in the United States. Six patients had no apparent risk factor for acquiring HTLV-I. These data demonstrate that HAM/TSP is occurring in the United States and that the diagnosis of HAM/TSP should be considered in patients with a slowly progressive myelopathy regardless of risk factors for acquiring HTLV-I.
Assuntos
Paraparesia Espástica Tropical/epidemiologia , Adulto , Soropositividade para HIV/epidemiologia , Humanos , Masculino , Paraparesia Espástica Tropical/complicações , Fatores de Risco , Estados Unidos/epidemiologia , Índias Ocidentais/etnologiaRESUMO
Human T-lymphotropic virus type I (HTLV-I) is associated with adult T-cell leukemia/lymphoma and with a chronic degenerative myelopathy. However, another major type of HTLV, HTLV-II, has been isolated only sporadically, and little is known of disease associations, transmission routes, and risk factors for HTLV-II infection. Recent studies indicate that a high percentage of certain groups of i.v. drug users and blood donors are infected with HTLV-II. Seroepidemiologic studies have found an elevated rate of seroreactivity to HTLV among Guaymi Indians from Bocas del Toro Province, Panama. To identify the cause of seroreactivity among this unique population we used HTLV-II-specific polymerase chain reaction techniques to detect HTLV genetic sequences from blood leukocytes of three seropositive Guaymi Indians. The HTLV-II primer-amplified polymerase chain reaction products from two of these subjects were partially sequenced and matched published HTLV-II nucleotide sequences in both p24 gag (94% of 107 bases) and pol (98% of 112 bases) regions. A CD4+ T-lymphocyte line established from one of these same subjects produced HTLV-II-specific proteins when tested in antigen-capture and immunoblot assays, as well as mature HTLV particles. The demonstration of HTLV-II infection in this geographically and culturally isolated Central American Indian population without typical risk factors for HTLV infection suggests that HTLV-II infection is endemic in this population and provides an important clue to potential natural reservoir for this virus.
Assuntos
Infecções por HTLV-II/epidemiologia , Vírus Linfotrópico T Tipo 2 Humano/isolamento & purificação , Sequência de Bases , Southern Blotting , Western Blotting , Anticorpos Anti-HTLV-II/análise , Antígenos HTLV-II/análise , Humanos , Indígenas Centro-Americanos , Dados de Sequência Molecular , Panamá , Reação em Cadeia da Polimerase , Linfócitos T/microbiologia , Linfócitos T/ultraestruturaRESUMO
The giant cholesterol cyst is a clinical entity distinct from cholesterol granulomas and other destructive lesions of the petrous bone. Preoperative assessment by computed tomographic scan and magnetic resonance imaging is extremely helpful. Attempts at total resection of the lesion are not necessary. Adequate surgical drainage may be established through the mastoid or middle fossa.