Effect of aging and diet restriction on monoamines and amino acids in cerebral cortex of Fischer-344 rats.

The effect of chronic diet restriction on amino acids and monoamines in cerebral cortex was studied in young and old male Fischer-344 rats. The effect of restricted feeding (60% of ad lib diet) was compared at 6 and 24 months of age. The results indicate that aging did not significantly alter the levels of norepinephrine (NE), dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in frontal (FCX), parietal (PCX) and occipital cortices (OCX). On the other hand, the effect of age on serotonin (5HT) was found to be regionally specific. The level of 5HT was 43% higher, while the ratio of 5HIAA/5HT was decreased 26% in OCX of 24 months old animals. In the FCX 5HIAA/5HT ratio was increased 27%. Diet restriction in old rats increased DA level markedly in FCX, and attenuated the age-related increase of 5HT level in OCX. The ratios of 5HIAA/5HT in FCX and OCX of DR animals were maintained at those found in the young ad lib (AL) group. The cortical neurotransmitter amino acids (aspartate, glutamate, gamma-aminobutyric acid, glycine and taurine) were well maintained during aging and dietary manipulation. Age-related reduction of cortical tryptophan and plasma ratio of tryptophan to large neutral amino acids in old animals were attenuated by chronic DR. The results suggest that serotonergic neurons are more susceptible to change during aging than are the catecholaminergic neurons. Diet restriction during the life of the animals appears to protect or attenuate the age-related changes in cortical serotonergic system while FCX dopamine concentrations were dramatically increased.     

Peripheral glomerular capillary wall lesions in IgA nephropathy and their implications

Peripheral glomerular capillary walls were studied in 26 cases of IgA nephropathy by means of the transmission electron microscope. Ultrastructural abnormalities were identified in 11 cases (42%). Abnormalities of the glomerular basement membrane (GBM) were the most frequent change which consisted of localized thinning, lamination, irregular thickening, disruption, membranolysis and aneurysmal dilatation of the GBM. Subendothelial electron dense deposits were seen. Necrosis and detachment of the podocytes from the GBM were also encountered. The changes were correlated with the clinical findings at the time of diagnosis which showed a significant correlation of these peripheral glomerular capillary wall lesions with proteinuria. With light microscopy, crescents were significantly more frequently seen in the cases showing the ultrastructural capillary wall abnormalities than those without. This observation suggested that local peripheral glomerular capillary wall damage was an important factor in the pathogenesis of the extracapillary lesions in IgA nephropathy.     

Thalassaemia in pregnancy

Thalassaemia is the most common monogenetic disease worldwide. Antenatal screening is effective and simple, and accurate genetic prenatal diagnosis can be achieved in early gestation. Less invasive methods are feasible with ultrasound fetal assessment for alpha-thalassaemia, analysis of circulating fetal nucleic acid in maternal plasma, and pre-implantation genetic diagnosis. Women with thalassaemia major and intermedia are at risk of various maternal complications, such as cardiac failure, alloimmunisation, viral infection, thrombosis, endocrine and bone disturbances. Therefore, it is prudent to adhere to a standard management plan in this group of pregnant women. Close monitoring of the maternal and fetal condition during pregnancy is essential, and various treatments, such as blood transfusion or postpartum prophylaxis for thromboembolism, may be indicated. After birth, resumption of iron chelation and bisphosphonates treatment is needed, and counselling on breast feeding and contraception should be given.     

Adenosquamous carcinoma presenting as liver abscess

Adenosquamous carcinoma (ASC) has a nonspecific presentation. We report a patient with ASC who presented with fever and epigastric pain. Computed tomographic findings and clinical features were suggestive of a liver abscess, while ultrasonography showed a complex space-occupying lesion. Biopsy revealed a lesion with malignant glandular and squamous components, a finding that was compatible with ASC. Complex space-occupying lesions should raise the suspicion of a mass lesion. Subtle imaging clues of a metastatic disease were reviewed retrospectively.     

Complexed prostate specific antigen provides significant enhancement of specificity compared with total prostate specific antigen for detecting prostate cancer

PURPOSE: Determining serum total prostate specific antigen (PSA) has proved to be a valuable diagnostic aid for detecting prostatic carcinoma, although the lack of specificity has limited its usefulness. Studies indicate that the use of percent free PSA would improve specificity while maintaining sensitivity. Since complexed PSA represents the major proportion of measurable PSA in serum, we determined whether it represents a single test alternative to the use of percent free PSA for the early detection of prostate cancer. MATERIALS AND METHODS: Archival serum was obtained from 385 men with no evidence of malignancy on biopsy and 272 with biopsy confirmed prostate cancer. We determined the concentration and proportion of total, complexed and free PSA. RESULTS: Receiver operating characteristics analysis using total PSA results from all samples (range 0.32 to 117 ng./ml.) indicated that the areas under the curve for complexed PSA alone as well as the free-to-total and complexed-to-total PSA ratios were similar and significantly greater than those for total PSA alone. Within the range of 85% to 95% sensitivity receiver operating characteristics analysis revealed that the specificity of complexed PSA was higher than that of total PSA and equivalent to that of the free-to-total PSA ratio. We noted a similar improvement in specificity in the 4 to 10 ng./ml. total PSA range. Using published cutoff values for complexed, total and percent free PSA when total PSA was in the 4 to 10 ng./ml. range the sensitivity and specificity of complexed and percent free PSA were similar. Within the 4 to 10 ng./ml. total PSA range the population of patients with no evidence of malignancy and complexed PSA below the upper limit was different with respect to total PSA from that with no evidence of malignancy and free PSA greater than 25%. CONCLUSIONS: The measurement of complexed PSA represents an alternative to the use of percent free PSA, although the patient populations identified by the 2 tests are different.     

Maturation of epididymal spermatozoa in the nondomesticated guinea pigs Cavia aperea and Galea musteloides

The physiological changes occurring in spermatozoa in the male reproductive tract of 2 nondomesticated species of South American guinea pigs with different mating systems were studied. Cavia aperea, the wild ancestor of the domesticated guinea pig, has a polygynous mating system, whereas Galea musteloides exhibits promiscuous mating behavior. The epididymis of both species resembled that of the domesticated guinea pig, with a swathe of tubule convolutions (linking the 2 major parts of the organ) that was of smaller size in Cavia but not Galea. Higher relative epididymal weight was demonstrated in the promiscuous species. During their journey through the epididymis, spermatozoa from Galea developed their potential for motility expression more proximally than did those of Cavia, but motility developed into forward progression in the same region in both species. The maximal velocities exhibited by mature Cavia sperm in vitro were greater than those of Galea. Spermatozoa from Cavia were twice the length of those from Galea, they had larger heads, and the acrosomes of single sperm were more sensitive to disruption during morphological preparation. Only in Cavia did agglutination of sperm into rouleaux occur, after the potential for motility had been developed. Migration of the cytoplasmic droplet along the midpiece occurred in the same regions in both species and before agglutination in Cavia. It is suggested that the male's reproductive strategy (polygyny vs promiscuity) dictates the size of the testis and epididymis, whereas the female's reproductive physiology (induced ovulation vs cyclicity) influences the posttesticular development of sperm morphology and motility in the epididymis.     

Biliary‐enteric bypass in unresectable malignant hilar biliary obstruction: Kwong Wah Hospital experience

Objective : To evaluate the efficacy of biliary‐enteric bypass in the palliation of malignant hilar biliary obstruction. Materials and Methods : Records of 19 patients from 1995 to 1998 were reviewed. There were 13 patients with cholangiocarcinoma and 6 patients with carcinoma of the gallbladder. Single biliary‐enteric bypass had been performed in 13 of the patients; the rest had more than one biliary‐enteric anastomosis. Results : The 30‐day mortality was 21% (4/19 patients). Bile leakage occurred in 2 patients, leading, in both, to fatality. Excluding the 30‐day mortality, the median survival of patients with carcinoma of the gallbladder and cholangiocarcinoma was 116 days (43–200) and 202 days (47–1207), respectively. The mean hospital stay was 31 days (13–59) and all patients were discharged with their symptoms relieved and a drop in bilirubin of at least two‐thirds their pre‐operative level. The late complication rate was 26.7% (4/15 patients). Conclusion : Biliary‐enteric bypass is effective in the palliation of symptoms of patients suffering from unresectable hilar biliary obstruction, although it carries considerable mortality and morbidity. Stenting, rather than surgery, should be considered for patients with unresectable gallbladder cancer.      

非小细胞肺癌中Per2的表达及其与预后的关系

目的：研究生物钟基因Per2在非小细胞肺癌（NSCLC）中的表达及其与预后的关系。方法：采用免疫组织化学染色法检测60例NSCLC组织和20例正常肺组织中Per2的表达,结合临床病理和随访资料进行分析。结果：在NSCLC组织和正常肺组织中Per2的阳性表达率分别为71.7%（43/60）和95.0%（19/20）,差异有统计学意义（P〈0.05）。NSCLC中Per2的表达缺失与分化程度及TMN分期相关（P〈0.05）,单因素分析结果表明Per2的表达状态与NSCLC的预后相关（P〈0.05）,多因素分析结果显示分化程度、TNM分期、淋巴结转移情况及Per2的表达状态均非影响NSCLC预后的独立危险因素（P〉0.05）。结论：Per2在NSCLC中表达降低,其阴性表达在NSCLC的发生和发展中起重要作用,影响NSCLC的预后。     

Prophylactic antibiotics in orthopaedic surgery: guidelines and practice

The national clinical practice guideline has recommended that prophylactic antibiotic be given in orthopaedic surgery involving joint replacements and internal fixation of fractures. The aim of this study is to assess the current antibiotics prophylaxis practice in a state level hospital. One hundred and three patients (68 males, 35 females; mean age 41.6 +/- 22.2 years) undergoing internal fixation for closed fractures and joint replacement surgery were included in this prospective study. The choice of pre and post-operative antibiotics, their dosages and duration of administration were recorded. The pre-operative antibiotics were only deemed to have been given if it was documented in the case notes and in the case of post-operative antibiotics if it was signed on the drug chart. Eighty eight percent were given pre-operative prophylactic antibiotics and 92% were given post-operative antibiotics. For patients undergoing internal fixation of fractures, the most commonly used antibiotic for both pre and post-op is intravenous cefuroxime. For joint replacement surgery, the most commonly used antibiotic is intravenous cefoperazone. The duration or number of doses of post-operative antibiotics was highly variable. It was not stated in 56% of the post-operative instructions. Post-operative antibiotic was ordered for 48 hours or longer in 10%. In conclusion, prophylactic antibiotics appear to be widely practised. The first line antibiotics as recommended by the present guideline were not given in any of the patients. Second generation followed by third generation cephalosporins are the most popular antibiotics, with a trend towards using third generation cephalosporins in arthroplasty patients. Single dose prophylaxis was rarely practised.     

An experience of renal replacement therapy in a combined neonatal and paediatric intensive care unit of Hong Kong

Intensive care services are expensive. The experience of developing a combined paediatric and neonatal intensive care unit (ICU) in a regional hospital is reported with reference to the provision of renal support for the critically ill patients. The combined unit is staffed by a team of paediatric intensivists, each of whom has special interest in a subspecialty, including cardiology, respiratory medicine, nephrology and neonatology. In the past 7 years, renal replacement therapy (peritoneal dialysis and haemofiltration) was provided to 40 patients, with comparable mortality and complication rates to other reports. This arrangement has been feasible and might be more efficient than running separate paediatric and neonatal ICUs or combining the paediatric ICU with the adult ICU.