Red cells in sickle cell crisis: observations on the pathophysiology of crisis

The pathophysiology of the occurrence and resolution of sickle cell crisis is unknown. The molecular abnormality is constant, while crisis is episodic. In the present study, red cell filterability and sickling with deoxygenation have been measured during sickle cell crises. Recovery from sickle crisis is associated with an increased filterability of the circulating red cell and a decreased susceptibility of the red cell to sickle with deoxygenation (p less than 0.05). The possibility that these changes are responsible for the resolution of crisis is suggested.     

Evaluation of some anthropometric indices for the diagnosis of obesity in pregnancy in Nigeria: a cross-sectional study

Background

Obesity in pregnancy is a global health problem which is associated with poor pregnancy outcomes. The use of weight and height, measured at about ten weeks of gestation, to produce pre-gestational body mass index is recommended for the diagnoses of the condition but limitations abound in under resourced settings.

Objectives

To measure anthropometric indices such as mid upper arm circumference, calf circumference, waist circumference and waist to hip ratio, for identification of obesity in pregnancy.

Methods

Anthropometric measurements were carried out on cohorts of pregnant women from 4 hospitals in Enugu, South-eastern Nigeria.

Results

There were no significant difference in the mean mid upper arm circumference (MUAC) and calf circumference (CC) across the trimester groups. The mean values of waist circumferences, hip circumference and waist to hip ratios changed significantly across the trimesters. The 75^th percentile of MUAC (33 cm) and CC (39 cm) in all trimesters, had sensitivity and specificity of more than 70% for identifying obesity in pregnancy.

Conclusion

MUAC and CC values of 33cm and 39cm respectively might be reliable cut off points for diagnoses of obesity throughout pregnancy in Enugu, Nigeria     

In vivo induction of type 1 and 2 immune responses against protein antigens

Polarization of the immune response towards Th1 or Th2 profiles is under the control of several, not yet well known, mechanisms. The present study was undertaken to investigate whether immune responses generated against major protein antigens, of parasitic (Schistosoma mansoni) and bacterial (Clostridium tetani) origin, present characteristic Th profiles. Mice were immunized with a single dose of S. mansoni 28 kDa glutathione-S-transferase (Sm28-GST) or tetanus toxin fragment c (TTc) in combination with different adjuvants, or Salmonelia typhimurium expressing these antigens as a fusion protein. Antigen- specific IgG isotypes and cytokine mRNA expression in vivo, as well as cytokine secretion after in vitro antigen stimulation were studied. Immunizations with either protein in aluminum hydroxide induced a strong Th2-associated antibody (IgG1) and cytokine (IL-4) response. In contrast, the recombinant S. typhimurium, expressing the TTc/Sm28-GST fusion protein, induced a Th1-like response, associated with the production of IFN-gamma and IgG2a antibodies against both antigens. When complete Freund's adjuvant was used, a non-polarized profile was observed, characterized by expression of both IL-4 and IFN-gamma, as well as strong specific IgG1 and IgG2a antibody responses. These results indicated that some protein antigens play a weak role in polarizing the immune response and that contrasting cytokine profiles could be induced against the same antigen, depending on the adjuvant employed.      

Effect of hormone replacement therapy,tibolone and raloxifene on serum lipids,apolipoprotein A1, apolipoprotein B and lipoprotein(a) in Greek postmenopausal women

The aim of this study was to assess the effect of estrogen, two regimens of continuous combined hormone replacement therapy (HRT), tibolone and raloxifene on serum lipid, apolipoprotein A1 and B and lipoprotein(a) levels in Greek postmenopausal women. A total of 350 postmenopausal women were studied in a prospective open design. Women were assigned to one of the following regimens depending on the presence of risk factors for osteoporosis, climacteric symptoms and an intact uterus: conjugated equine estrogen 0.625 mg (CEE, n=34), continuous combined CEE 0.625 mg plus medroxyprogesterone acetate (MPA) 5 mg, (n=80), continuous combined 17β-estradiol 2 mg plus norethisterone acetate (NETA) 1 mg (n=58), tibolone 2.5 mg (n=83) and raloxifene HCl 60 mg (n=50). Forty-five postmenopausal women with no indications for HRT served as controls. Total cholesterol (TC), low-density lipoprotein (LDL) cholestrol and high-density lipoprotein (HDL) cholesterol, triglyceride (TG), apolipoprotein A1 (ApoA₁), apolipoprotein B (ApoB) and lipoprotein(a) (Lp(a)) levels were assessed in each subject at baseline, and at 6 and 12 months of therapy. All therapy regimens lowered TC levels compared to baseline (4.2-8.0% decrease). This effect was more prominent in the subgoup of women with high baseline TC levels (9.1-20.4% decrease). LDL cholesterol decreased significantly in CEE, CEE/MPA and raloxifene groups (?11.2%, ?11.9% and ?11.0%, respectively). Hypercholesterolemic women exhibited a steeper decrease in LDL cholesterol (10.6-27.8% in all therapy groups). TG levels increased significantly in the CEE and CEE/MPA groups (23.7% and 21.8%, respectively), while estradiol/NETA had no effect on TG levels. Tibolone decreased TG levels markedly, by 20.6%, while raloxifene had no TG-lowering effect. HDL cholesterol and ApoA₁ were increased by CEE and CEE/MPA (HDL cholesterol, 7.4% and 11.8%, respectively; ApoA₁, 17.8% and 7.9%, respectively) and decreased by tibolone (HDL cholesterol, ?13.6%; and ApoA₁, ?9.9%). All therapy regimens except raloxifene lowered Lp(a) levels, with tibolone having the more pronounced effect (?13.2 to ?29.0%). In conclusion, each therapy regimen had a different effect on lipid-lipoprotein levels, exerting favorable and unfavorable modifications. Hypercholesterolemic women seemed to benefit more from the cholesterol-lowering effect of estrogen replacement therapy/HRT. The choice for a particular regimen should be based on individual needs, indications and lipid-lipoprotein profile.     

Suspected recurrent rectosigmoid carcinoma after abdominoperineal resection: MR imaging and histopathologic findings

Eleven patients who underwent abdominoperineal resection for rectosigmoid carcinoma were examined with magnetic resonance (MR) imaging for suspected recurrent tumor in the presacral space. There were 12 suspected masses in the 11 patients. Ten lesions were malignant, and in two lesions only nonneoplastic inflammatory tissue was found. The signal intensity (SI) of each lesion relative to that of muscle was determined visually and correlated with the histologic findings at surgery or biopsy. The SIs of malignant and benign lesions were indistinguishable. All lesions showed areas of high SI that correlated with carcinoma and tumor necrosis or with non-neoplastic inflammation and edema. Areas of low SI corresponded to reactive fibrous tissue (desmoplastic reaction) with small islands of tumor or to nonneoplastic fibrosis. MR imaging can be useful in determining the extent of suspected tumors, but SIs on T2-weighted images do not permit histologic diagnosis. In particular, distinction of benign from malignant tissue is difficult in tumors with a desmoplastic reaction.