Hb Frankfurt: Ein neues instabiles Hämoglobin

Zusammenfassung In einer deutschen Sippe wurde ein anomales Hämoglobin gefunden, das bei den Betroffenen eine Heinz-Körper-Anämie verursacht. Es handelt sich um ein hitzelabiles Hämoglobin.Die Anomalie dieses instabilen Hb ist in der Nicht--Kette lokalisiert.Die Polypeptidketten dieses Hb wurden mittels Ionenaustauscher-Chromatographie voneinander getrennt. Nach anschließender Reinigung durch Gel-Filtration wurde die Nicht--Kette mit Hilfe des Fingerprintverfahrens und der quantitativen Aminosäuren-Analyse weiter untersucht. Es fanden sich multiple Abweichungen in der Aminosäurenzusammensetzung. Danach kann die Anomalität nicht wie bei den bislang bekannt gewordenen anomalen Hämoglobinen durcheinen Aminosäurenaustausch verursacht sein.Hb Frankfurt ist wahrscheinlich das Ergebnis eines crossover-Lepore-Hb- oder einer Deletion bzw. Insertion von ein oder zwei Nukleotiden auf der DNS- bzw. RNS-Kette.     

Pyelonephritic Escherichia coli expressing P fimbriae decrease immune response of the mouse kidney

P fimbriae are proteinaceous appendages on the surface of Escherichia coli bacteria that mediate adherence to uroepithelial cells. E. coli that express P fimbriae account for the majority of ascending urinary tract infections in women with normal urinary tracts. The hypothesis that P fimbriae on uropathic E. coli attach to renal epithelia and may regulate the immune response to establish infection was investigated. The polymeric Ig receptor (pIgR), produced by renal epithelia, transports IgA into the urinary space. Kidney pIgR and urine IgA levels were analyzed in a mouse model of ascending pyelonephritis, using E. coli with (P+) and without (P-) P fimbriae, to determine whether P(+) E. coli regulate epithelial pIgR expression and IgA transport into the urine. (P+) E. coli establish infection and persist to a greater amount than P(-) E. coli. P(+)-infected mice downregulate pIgR mRNA and protein levels compared with P(-)-infected or PBS controls at > or =48 h. The decrease in pIgR was associated with decreased urinary IgA levels in the P(+)-infected group at 48 h. pIgR mRNA and protein also decline in P(+) E. coli-infected LPS-hyporesponsive mice. These studies identify a novel virulence mechanism of E. coli that express P fimbriae. It is proposed that P fimbriae decrease pIgR expression in the kidney and consequently decrease IgA transport into the urinary space. This may explain, in part, how E. coli that bear P fimbriae exploit the immune system of human hosts to establish ascending pyelonephritis.     

Dopamine is metabolised by different enzymes along the rat nephron

The purpose of this study was to determine the basal levels of dopamine (DA) and to examine the enzymes involved in DA metabolism in different microdissected nephron segments from rat kidneys. Segments were incubated with DA (50 nM) or DA plus monoamine oxidase (MAO) or catechol-O-methyl transferase (COMT) inhibitors. Basal DA levels were higher in the proximal convoluted tubule (PCT, 10.8±3.7 pg/mm) and in the medullary collecting duct (MCD, 10.9±4.0 pg/mm) than in the medullary thick ascending limb of Henles loop (MTAL, 4.9±0.9 pg/mm) (P<0.05). The percentage of exogenously added DA that was not metabolised was similar in both PCT (67±13%) and MCD (65±5%) and lower in MTAL (35±7%), suggesting that MTAL is a major site of DA metabolism. Inhibition of MAO (pargyline 1 mM) significantly increased the basal content of DA and the percentage of the added non-metabolised DA (to 95±10%) in PCT but had no effect on MTAL or MCD. Conversely, inhibition of COMT (nitecapone or Ro-41-0960, both 1 mM) slightly increased the basal levels of DA only in MTAL, whereas the percentage of added DA not metabolised rose to 97±10% in MTAL and to 91±15% in MCD. COMT inhibition had no effect in PCT. In conscious rats pargyline (50 mg/kg) increased urinary DA from 680±34 to 1,128±158 ng/d/100 g BW (P<0.01) while nitecapone (40 mg/kg) produced a slight non-significant increment. Our results show that DA is present all along the rat nephron and that renal DA is metabolised continuously and predominantly by MAO in proximal segments, and by COMT in the more distal ones.     

Recurrent neuroblastoma with gastric invasion

The authors present an unusual manifestation of neuroblastoma in a young child: upper gastrointestinal bleeding due to erosion of the tumor into the stomach. Included are reviews of gastrointestinal manifestations of neuroblastoma and gastric tumors in children.     

Adenocarcinoma of the cervix and vagina in pediatric patients

Here we report our combined analysis of vaginal mesonephric adenocarcinoma (MA) in a 13 years old treated at our institution and of reported vaginal or cervical MA and clear-cell adenocarcinoma in 37 patients 18 years old or younger. Tumors in 27 patients arose in the vagina; 8 (21%) had metastases at diagnosis. The predominant symptom was vaginal bleeding; 62% of patients were exposed to diethylstilbestrol in utero. The 3-year survival estimate was 71% +/- 11%. Surgical treatment and metastasis at diagnosis were significant predictors of survival. The association between tumor excision and excellent outcome suggests that radical hysterectomy or pelvic exenteration is unnecessary. Radiotherapy as an adjunct may have contributed to this outcome.     

Usefulness of EQ-5D in Assessing Health Status in Primary Care Patients with Major Depressive Disorder

Objectives  

Major depressive disorder (MDD) is a prevalent psychiatric disorder associated with impaired patient functioning and reductions in health-related quality of life (HRQL). The present study describes the impact of MDD on patients' HRQL and examines preference-based health state differences by patient features and clinical characteristics.