Minimal vs median sternotomy for aortic valve replacement

The aim of this study was to compare postoperative outcomes in patients undergoing aortic valve replacement through a ministernotomy or conventional sternotomy. Sixty patients were randomized into 2 groups of 30 each: group 1 had a full sternotomy and group 2 had a ministernotomy. Pain was evaluated on a daily basis, pulmonary function tests were performed perioperatively. The skin incision was shorter in group 2 (7.17 vs 24.50 cm in group 1). There was significantly less mediastinal drainage in group 2 (233 vs 590 mL in 24 hours in group 1). Group 1 patients had more blood transfusions and longer ventilation time. In group 1, 96.7% experienced severe pain, whereas 93.3% in group 2 reported minimal pain. Hospital stay was 17.7 days in group 1 and 8.0 days in group 2. The ministernotomy had a cosmetic advantage, less blood loss and transfusion requirement, greater sternal stability, better respiratory function, and earlier extubation and hospital discharge.     

The relationship between nighttime dipping in blood pressure and cerebral hemodynamics in nonstroke patients

Inadequate dipping in nighttime blood pressure (BP) is associated with cerebrovascular disease. The authors aimed to determine whether inadequate nocturnal dipping was associated with abnormalities in cerebrovascular hemodynamics in individuals without stroke. Participants in this study underwent 24-hour ambulatory BP monitoring followed by morning transcranial Doppler measurements of blood flow velocities (BFVs) in the middle cerebral artery during supine rest, head-up tilt, hypocapnia, and hypercapnia. Nighttime BP decline by <10% was considered nondipping. Of the 102 nonstroke participants (mean age, 53.6 years), 35 (34%) were dippers. Although nondippers had similar BFV and cerebrovascular resistance (CVR) while supine, they had a lower BFV (P=.04) and greater CVR (P=.02) during head-up tilt compared with dippers. Moreover, greater nighttime dipping in both systolic BP (P=.006) and diastolic BP (P=.03) were associated with higher daytime BFV and lower CVR (P=.01 for systolic BP; P=.02 for diastolic BP). Inadequate nocturnal BP dipping is associated with lower daytime cerebral blood flow, especially during head-up tilt.     

The value of simultaneous co-registration of 99mTc- MDP and 131Iodine in metastatic differentiated thyroid carcinoma

BACKGROUND: The lack of anatomical details in standard (131)Iodine whole body scanning ((131)I WBS) interferes with the proper localization of metastatic differentiated thyroid carcinoma (DTC) lesions. In addition, nearby or overlapping variable physiological distribution of (131)I may affect the specificity of (131)I uptake, giving indeterminate results. The aim of this study was to demonstrate the clinical usefulness of simultaneous co-registration of (99m)Tc MDP bone scanning as an anatomical landmark with (131)I scanning in the evaluation of metastatic DTC. MATERIAL AND METHODS: Twenty-five patients (16 females and 9 males, mean age +/- SD = 52 +/- 13 years) with metastatic DTC (17 papillary, 8 follicular), were included. Whole body scanning using a 256 x 1024 matrix and an 8 cm/min scan rate were obtained 48 hours after oral administration of 185-370 MBq 131I and 2 hours after IV administration of 185-370 MBq (99m)Tc MDP using a dual head gamma camera equipped with high energy parallel hole collimators. Occasionally, additional simultaneous co-registration of localised detailed images was also performed using a 256 x 256 matrix size. The two planar images were fused with optional fusion of SPECT images. The data from standard (131)I scanning and fused (131)I/ (99m)Tc-MDP scanning were separately assessed by two nuclear medicine physicians. Fusion images were considered to improve image interpretation in comparison with standard (131)I scanning when they provided better localization of lesions. RESULTS: All lesions in the present study were validated by radiological images and clinical follow up for at least 12 months. Forty-eight metastatic lesions were confirmed as follows: 2 in the skull, 10 in the neck, 20 in the thorax, 12 in the pelvic-abdominal region and 4 in the extremities. Standard (131)I WBS showed 54 extra-thyroidal foci with 8 false positive lesions of which 2 were located in the scalp and 6 in the pelvic-abdominal region extra-skeleton (i.e. sensitivity 100%, specificity 86%). Out of the 48 validated lesions, 16 were indeterminately localized: 10 in the thorax (3 mediastinal nodal lesions, 5 vertebral lesions and 2 ribs) and 6 in the pelvic-abdominal region (2 upper sacral, 2 sacroiliac region and 2 ischial bone). Fusion images confirmed the precise localization of the pathological uptake in the validated 48 lesions (sensitivity 100%, specificity 100%). There were 2 (4%) indeterminate lesions in fused planar imaging that were clearly localized via fused SPECT images. CONCLUSIONS: Fusion images using simultaneous co-registration of (131)I and (99m)Tc MDP scanning is a simple and feasible technique that improves the anatomically limited interpretation of scintigraphy using (131)I alone in patients with metastatic differentiated thyroid carcinoma. The diagnostic advantage of this technique seems to be more apparent in the thoracic and pelvic- abdominal regions in contrast to the neck and extremities.     

Does chemical sympathectomy alter the ontogeny of gubernacular migration in vivo?

Background

Testicular descent occurs in several stages, but the exact mechanism remains obscure. Sympathetic nerves have been proposed to have a role by a possible action on developing cremaster muscle, following observations of sympathetic dysfunction in cremaster from boys with cryptorchidism. This study aimed to see if chemical sympathectomy affected testicular descent in rats.

Methods

Sprague-Dawley dams were injected with 6-hydroxydopamine (days 15-19; 75 μg/kg) or control vehicle alone, and male pups examined at 0 to 10, 20, 30, and 60 days of age. The length of the processus vaginalis was measured and sections taken for histology.

Results

No difference in processus vaginalis growth was found between experimental and control groups, both macro- and microscopically. Chemical sympathectomy was confirmed by loss of adrenergic fibres in the adrenal cortex of experimental, but not control, animals.

Conclusions

These studies suggest that sympathetic innervation is not an important part of testicular descent in the rat but does not exclude a pathologic role in undescended testes or effects in humans only.     

The anatomy of the cremaster muscle during inguinoscrotal testicular descent in the rat

Background

Extrapolation of rat testicular descent studies to humans has been criticized because of anatomical differences of the cremaster muscle. Human cremaster is described as a thin strip rather than a large, complete sac as in rats, which is proposed to be more important in propelling the testis during descent. This study investigated cremaster muscle anatomy and ontogeny in both normal and cryptorchid rat models.

Methods

Gubernacula from 4 groups of neonatal rats were sectioned longitudinally and transversely: normal Sprague-Dawley, capsaicin pretreated, flutamide pretreated, and congenital cryptorchid rats. Gubernacula were stained with hematoxylin-eosin, Masson trichrome, and desmin immunohistochemistry to study muscle development.

Results

Myoblasts are more numerous at the gubernacular tip, whereas the most differentiated muscle is proximal. Rat cremaster develops as an elongated strip rather than a complete sac derived from abdominal wall muscles. Flutamide and capsaicin pretreatment disrupts development.

Conclusion

Rat cremaster muscle develops as a strip, bearing close resemblance to human cremaster muscle, permitting extrapolation of cremaster function to human testicular descent. The cremaster muscle appears to differentiate from the gubernacular tip during elongation to the scrotum, and requires intact sensory innervation and androgen.     

Sequence diversity of the haemagglutinin open reading frame of recent highly pathogenic avian influenza H5N1 isolates from Egypt

Archives of Virology - The sequences encoding the haemagglutinin (HA) of twelve H5N1 isolates obtained in 2006 and 2007 from different avian species in backyard holdings and poultry farms in Egypt...     

A study of the effect of splenectomy on hepatic functional reserve and structural damage in patients with chronic hepatitis C virus infection by non-invasive serum markers. A prospective study

Several beneficial effects of splenectomy on the liver integrity have been recently reported by both experimental and clinical studies. However, the effects of splenectomy on hepatic functional reserve and structural damage in patients with chronic hepatitis C (CHC) were not studied by objective evidence. The aim of this study was to assess the effect of splenectomy on hepatic functional reserve and structural damage in patients with CHC by non-invasive serum markers. The study involved 22 patients with histopathological diagnosis of CHC undergoing splenectomy for treatment of associated hypersplenism. The hepatic functional reserve and structural damage markers were assessed before and after splenectomy surgery on the 2nd and 60th postoperative days by aspartate aminotransferase to alanine aminotransferase (AST/ALT ratio), AST to platelet ratio index (APRI) and serum levels of gamma-glutamyl transferase (GGT), hyaluronic acid (HA), type IV collagen (CIV) and tissue inhibitor of metalloproteinase-1 (TIMP-1). After splenectomy, the levels of serum HA showed a significant decrease in relation to the preoperative values both in PO-1 (mean pre-splenectomy: 272+/-88.6 versus 185+/-77.4 ng/ml; P=0.01) and PO-2 (169+/-58.1 ng/ml; 0.017). The levels of type IV collagen showed a significant decrease in relation to the preoperative values both in PO-1 (mean pre-splenectomy: 208+/-134 versus 125+/-100 ng/ml; P=0.01) and PO-2 (121+/-74.7 ng/ml; P=0.02). Serum levels of TIMP-1 also showed a significant decrease in relation to the preoperative values both in PO-1 (mean pre-splenectomy: 764+/-571 versus 261+/-195 ng/ml; P=0.006) and PO-2 (149+/-110.1 ng/ml; P=0.004). There was no significant difference between PO-1 and PO-2 mean values for each of those serum markers. This study found that splenectomy induced a reduction of biochemical markers of liver functional reserve and fibrosis in patients with chronic hepatitis C which reflect a change in the processes involved in of liver fibrosis. However, it cannot be concluded whether this reflects a change in the rate of its progression or a prevention of further fibrosis.