[Progress in research of models for predicting the risk of readmission and mortality among patients with acute heart failure]

Heart failure is a serious and end-stage status of various heart diseases, characterized by comparatively high rate of readmission and mortality, and has become an important public health issue. The risk of readmission and mortality following discharge of an index hospitalization are key indicators to evaluate the quality of medical care among patients with acute heart failure. Therefore, it is important to carry out risk prediction research for patients with acute heart failure, quantify the disease risk, perform risk stratification, optimize clinical decision-making, elevate patients' quality of life and prognosis, and comprehensively improve the medical quality of acute heart failure. During the past 20 years, foreign researchers have developed dozens of models to predict the risk of acute heart failure readmission and mortality, and Chinese researchers have also developed up to 10 models applicable to the Chinese population. However, there is no recommended risk prediction model for acute heart failure in current clinical guidelines across China. In this report, we aim to introduce the major models for predicting the risk of acute heart failure readmission and mortality from home and abroad, focus on putting forward limitations of established models, and initiating potential directions for future studies from the following aspects: integrate multi-source data, mine emerging biomarkers, establish polygenic risk scores, optimize machine learning methods, promote flexible adjustment, and broaden approaches that applicable for various scenarios. Accordingly, this study will help facilitate domestic research in predicting the risk of readmission and mortality among patients hospitalized for acute heart failure.

[Research progress of LI-RADS categories and imaging features in predicting the prognosis of liver tumors]

The liver imaging reporting and data system (LI-RADS) is an imaging assessment system that standardizes the diagnosis of hepatocellular carcinoma (HCC), indicating the benign and malignant tumor through categories as well as major and ancillary features. The higher the LI-RADS category ranking, the higher the corresponding HCC likelihood and malignancy risk. Therefore, early diagnosis and prediction of the prognostic risk factors of liver tumors by preoperative imaging have important clinical significance for improving the survival rate and prognosis of patients. This article reviews the research progress of LI-RADS categories and related imaging features in predicting the prognosis of liver tumors.

[Research progress of cirrhotic portal hypertension in diagnostic imaging methods]

Hepatic venous pressure gradient measurement via jugular vein catheterization is still currently the gold standard for evaluating portal hypertension. However, how to accurately and reproducibly assess whether there is portal hypertension has always been a concern in patients with liver cirrhosis. In recent years, imaging methods have made significant progress in the non-invasive diagnosis of portal hypertension. This paper reviews the current different diagnostic value of imaging methods and related research progress in an attempt to evaluate patients with cirrhotic portal hypertension.

[Research progress of magnetic resonance imaging in hepatocellular carcinoma]

Hepatocellular carcinoma (HCC) is the most common malignant tumors of liver. Rational treatment in early stage of HCC can significantly increase the survival rate of patients. Detection of early-stage liver lesions through diffusion-weighted imaging, diffusion kurtosis imaging, incoherent motion within voxels, magnetic resonance spectroscopy imaging, dynamic contrast-enhanced imaging, or other functional imaging can accurately evaluate grade of malignancy and guide towards the curative effect of different treatment schemes. Volumetric interpolated breath-hold examination (VIBE) with three techniques, namely, CAIPIRINHA, Dixon, and TWIST, i.e., CDT-VIBE sequence can provide multiple sets of arterial phase images in a short time, and detect small foci transient enhancement that cannot be detected by other examinations, and the differences in initial enhancement phase of apparent lesions are of great significance for suggesting hemodynamic characteristics. In addition, magnetic resonance imaging predicts microvascular invasion of HCC, i.e., indirectly predicts HCC lesions recurrence rate, and overall survival time after liver transplantation. This article reviews the current research progress of magnetic resonance imaging technology in HCC.

Characterization of bacterial microbiota diversity in Tibetan pigs fed with green forage in Linzhi of the Tibet autonomous region

The acute shortage of forage resources is a serious problem for Tibetan pigs in the Tibet region, and the composition of feed can change the structure of the intestinal flora. This study first reported the effect of Alfalfa and Chenopodium glaucum feeding on the microbial diversity in Tibetan pigs, contributing to the forage exploitation of Tibetan pigs in the Tibet region.

[The expression of P19ink4d in the pathogenesis and development of hearing loss]

Objective: This study aimed to investigate the P19ink4d expression in cochlea of mice model with noise induced hearing loss and the role of P19ink4d in the degeneration of inner ear cells. It also searched for P19ink4d gene alterations in patients with profound sensorineural deafness.Method: CBA/J mice were exposed to broad band noise at 101 dB SPL for 2 hours, auditory brainstem response (ABR) were examined to confirm noise lead to the permanent threshold shift. Immunohistochemical staining, Western blotting, and real-time polymerase chain reaction (PCR) were performed on cochlear tissues, to elucidate changes in P19ink4d expression in mice after noise exposure. For clinical evaluation, 400 children from unrelated families with severe or profound sensorineural hearing loss (SNHL) were recruited, genomic DNA was obtained from the patients and was subjected to DNA microarray to screen mutations in 4 most common genes. The sample that carried none of the common mutant alleles were subjected to PCR and sequenced to detect mutations in P19ink4d gene.Result: The ABR threshold shift of mice in the experimental group significantly increased after noise exposure and was higher than that in the null-noise group. The ABR of 1 day post noise was least among experimental groups and there is no statistical different between ABR of 7 days and 14 days post noise. The missing of outer hair cells occurred after noise exposure, while the inner hair cells hardly miss. It was found that the P19ink4d expression increased significantly in the inner ear cells 3 hours after noise exposure, then recovered in 24 hours. Western blot indicated that the amount of P19ink4d increased transitorily 3-6 h after the noise. However, no mutation existed within the coding exons of P19ink4d in the patients with profound sensorineural deafness.Conclusion: The results support the concept that P19ink4d may play an important role in the pathogenesis and development of noise induced hearing loss.

Isolation and identification of pathogenic Aeromonas veronii from a dead Yangtze finless porpoise

Diseases caused by Aeromonas veronii in freshwater fish have been widely reported, but other species such as aquatic mammals have probably been overlooked. Here, we identified one isolate of A. veronii from a Yangtze finless porpoise Neophocaena asiaeorientalis asiaeorientalis exhibiting disease and mortality, and subsequently confirmed its virulence in artificial infection of BALB/c mice. The bacterial isolate was identified as A. veronii based on physiological, biochemical, and phenotypic features, and homology of the 16S rRNA, cpn60, rpoB, dnaJ and gyrB genes. Our results expand the known host spectrum of A. veronii, which is of great importance for the etiology of porpoise, dolphin, and other cetacean diseases.

Antibiotic resistance and screening of the resistant genes of Escherichia coli (E. coli) isolated from diarrheal yak calves in Sichuan Province, China

This study was conducted to determine the antibiotic and screening resistance genes of Escherichia coli (E. coli) isolated from diarrheal yak calves from high remote plateau in Sichuan, China. A total 41 rectal swabs were obtained from diarrheal yak calves. E. coli were isolated and identified. The antimicrobial sensitivity was tested by piloting the disk diffusion method for 21 antibiotics. Polymerase chain reaction was employed to detect the resistance genes. The results showed that the drug resistance ranged from 2.4% (amikacin) to 53.7% (tetracycline), while no isolates were found resistant to neomycin and polymyxin B. Multi-drug resistance was detected in 4.9% isolates to 17 antimicrobial agents; and 24.4% isolates were found susceptible to all antimicrobial agents. The aminoglycoside resistance genes of aac(3)-lla, ant(3')-la and aph(3')-lla was positive in 4.9%, 2.1% and 7.3% E. coli isolates respectively. The 4.9% and 2.1% of E. coli isolates were detected in b-Lactam resistance genes of TEM and CTX-M, respectively; and 12.2% and 4.9% of E. coli isolates were found to have Tetracycline resistance genes of tetM and tetA, respectively. The present study reveals that the yak calves from high cold plateau are potential reservoir of E. coli with widely distributed multiple drug resistance which requires the attention of concerned authorities regarding the use of non-standard antibiotics.

The importance of expressing PDCD4 and PDCD5 anti-oncogenes in glioma

Glioma is the most common malignant tumor of the brain, which is difficult to be completely resected. The recurrence and mortality rates are high and the prognosis is poor. The aim of this study was to investigate the expression of anti-oncogene programmed cell death 4 (PDCD4) and programmed cell death 5 (PDCD5) in glioma and their influence on the progression of the disease in order to provide new therapeutic approaches. Reverse transcription polymerase chain reaction (RT-PCR) analysis was used to investigate PDCD4 mRNA and PDCD5 mRNA expression in 66 glioma patients who served as the study group and 22 patients who suffered from craniocerebral injuries or hematencephalon who were used as controls. The experimental group was divided into a low malignant group (tumors grade I - II) and a high malignant group (tumor grades III-IV). The PDCD4 mRNA and PDCD5 mRNA expression in the experimental group was 0.545±0.202 and 0.687±0.174 and in the control group was 0.942±0.131 and 0.868 ± 0.190, respectively (P less than 0.05). The PDCD4 mRNA and PDCD5 mRNA expressions in the low malignant group were 0.628±0.240 and 0.750±0.198, respectively, and in the high malignant group were 0.464±0.185 and 0.553±0.170, respectively (P less than 0.05). The results showed a downregulation of PDCD4 mRNA and PDCD5 mRNA expression in the experimental group compared with the control group. This downregulation was correlated with the pathological grade of glioma. In the high malignant group the PDCD4 mRNA and PDCD5 mRNA expressions were significantly decreased compared with the low malignant group and the control group. PDCD4 mRNA and PDCD5 mRNA expressions are promising targets for the diagnosis and treatment of glioma.

Neferine Protects Endothelial Glycocalyx via Mitochondrial ROS in Lipopolysaccharide-Induced Acute Respiratory Distress Syndrome

Damage to the endothelial glycocalyx is a critical factor in increased pulmonary vascular permeability, which is the basic pathological feature of acute respiratory distress syndrome (ARDS). Neferine (Nef), a bisbenzylisoquinoline alkaloid isolated from green seed embryos of Nelumbo nucifera Gaertn, has extensive pharmacological activity. In this study, we showed that Nef reduced lung-capillary permeability, down-regulated the production of cytokines (IL-1β, IL-6, TNF-α, and IL-10) and inhibited the activation of the NF-κB signaling pathway in mice with lipopolysaccharide (LPS)-induced ARDS. Further analysis indicated that Nef provided protection against endothelial glycocalyx degradation in LPS-induced ARDS mice (in vivo) and in LPS-stimulated human umbilical vein endothelial cells (in vitro). The glycocalyx-protective effect of Nef may be initiated by suppressing the production of mitochondrial ROS (mtROS) and decreasing oxidative damage. Nef was also found to promote glycocalyx restoration by accelerating the removal of mtROS in endothelial cells in LPS-induced ARDS. These results suggested the potential of Nef as a therapeutic agent for ARDS associated with Gram-negative bacterial infections and elucidated the mechanisms underlying the protection and restoration of the endothelial glycocalyx.

The role of osteopontin and its receptor in meningioma development and progression

Meningiomas are common in intracranial tumors, the majority of which are benign with slow growth and low recurrence rate. The aim of the present study was to assess the role of osteopontin and its receptor CD44 (Cluster of differentiation -44) in meningioma development and progression. A total of 2 groups were included, namely an experimental group with 54 meningioma patients and a control group with 30 patients with internal and external decompression. The disease group included subjects, from whom meningioma tissue specimens were collected during surgery for tumor excision, whereas the control group included subjects who were subjected to scalp laceration and provided normal meninx tissues. The expression of osteopontin and CD44 was determined by immunohistochemistry. Osteopontin expression was negative in normal meninx, and its expression was increased in meningioma tissues (P less than 0.05). The positive expression of osteopontin increased according to the histological grade of meningioma (r=0.417, P less than 0.001). A highly significant difference was noted between non-invasive and invasive meningiomas (P less than 0.001). The positive expression of CD44 correlated with the grade of meningioma and its invasiveness (P less than 0.05), although it exhibited no correlation with the degree of peritumoral edema (r=0.033, P>0.05). The increased expressions of osteopontin and CD44 were observed in all grades of meningioma, and correlated with its development (r=0.961, P less than 0.001). Osteopontin and CD44 play important roles in the development and progression of meningioma and can be used as prognostic markers for tumor recurrence and progression as well as therapeutic targets for the development of new drugs.

Prevalence, associated risk factors, and phylogenetic analysis of Echinococcus granulosus isolated from freerange Tibetan pigs in Tibet, China

The current study was performed to investigate the prevalence, associated risk factors exploration and phylogenetic analysis of Echinococcus granulosus (E. granulosus) genotypes isolated from Tibetan pigs. A total 373 Tibetan pigs were examined during 2014 and 2015, and the variables potentially associated with E. granulosus infection were explored with a multivariable logistic regression model. E. granulosus cysts (n=37) were collected from Tibetan pigs (lungs or livers). Fragments amplification of mitochondrial (mt) DNA of cox1 (shorter and longer) and atp6 were employed. The genotype of E. granulosus were identified by sequence and phylogenetic analysis. Results showed the prevalence of E. granulosus in Tibetan pigs was 9.9%. The prevalence of E. granulosus in male and female Tibetan pigs was 6.8% and 13.3%, with a significant difference in the two genders (P<0.05). In different seasons, the infection rate of E. granulosus in Tibetan pigs were ranged from 5.8% to 12.3%. E. granulosus infection rates in different growing stages of Tibetan pigs were ranged from 4.4% to 15.9%, with a statistical difference in the three stages (P<0.01). The prevalence of E. granulosus in Tibetan pigs were 7.9% in 2014 and 13.0% in 2015. Genders and growing stages were demonstrated to be risk factors to influence the prevalence significantly through multivariable logistic regression model. All the three fragments were successfully amplified from each of the 37 cysts. E. granulosus genotypes of G4 and G6 were identified by comparing with reference sequences of E. genotypes available at NCBI database and phylogenetic analysis by using MEGA software.

Coagulation in hindbrain membrane meningioma patients treated with different injections using acute hypervolemic hemodilution

The aim of this study was to analyze the changes in coagulation in meningioma patients treated with different injections using the method of acute hypervolemic hemodilution (AHH). One hundred fifty hindbrain membrane meningioma patients were randomly divided into 5 groups, 30 per group. The first group were injected 40ml/time with Danhong after anesthesia induction; the second group were injected with 40ml~60ml/time Kangai and combined with interventional chemotherapy and embolization procedure; the third group of AHH were injected with polygeline 15ml/kg; the fourth group were injected with hydroxyethyl starch (130/0.4) sodium chloride in doses of 15ml/kg; the control group underwent basic treatment for lowering blood pressure and lowering blood fat. The changes of coagulation index were recorded before and after surgery and before and after the injection of different medications. Compared to the control group, for the first group of AHH, after being treated for 10 days and 30 days, the concentrations of bone specific alkaline phosphatase (BALP), bone Gla protein (BGP) and pro-collagen carboxy-terminal propeptide (PICP) were higher than that of the control group, the levels of endotoxin (ET) and C-reactive protein (CRP) were decreased compared to the control group (p less than 0.05); for the second group of AHH, after being treated for 10 days, the index of prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen (Fg) were not significantly changed, but the related level of vascular endothelial growth factor (VEGF) significantly decreased (p less than 0.05). Comparing the coagulation function index after surgery in the third and fourth groups, there were no significant changes in mean arterial pressure (MAP) level, heart rate (HR) value presented a low decrease, central venous pressure (CVP) level increased and the level of interleukin IL-6 showed a steady state after increasing. Analyzing the levels of interleukin IL-8 and tumor necrosis factor-α (TNF-α) after surgery, it was seen that in the third group they increased and in the fourth group they decreased (p less than 0.05). Danhong injection improved the coagulation function and microcirculation of patients, Kangai injection and interventional chemotherapy and embolization restrained the appearance of tumor angiogenesis, AHH operation with polygeline injection and hydroxyethyl starch (130/0.4) sodium chloride kept blood flow in normal parameters.

Molecular characterization of ascaris from Tibetan pigs by three mitochondrial markers of nad1, cox1 and cox2

Ascaris is a helminthic parasite, which infects a wide range of host species causing ascariasis, a predominant disease worldwide. This parasite causes significant economic losses to the pig industry. The current study was designed to determine the Ascaris nematode by the genetic characterization of three mitochondrial (mt) genes namely NADH dehydrogenase subunit 1 (nad1), cytochrome oxidase subunit 1 (cox1) and cytochrome oxidase subunit 2 (cox2). A high infection rate of Ascaris nematode has been found in Tibetan pigs at the slaughter houses in Tibet Autonomous Region of China. The nad1, cox1 and cox2 genes sequences collected from adult Ascaris individuals were amplified by polymerase chain reaction. The cloned-amplicons and the positive products were sequenced and phylogenetic analysis was performed. The results indicated that the Ascaris infecting the Tibetan pigs were Ascaris suum (A. suum). This is the first report on the isolation, identification and genetic characterization of three mitochondrial genomes (nad1, cox1, and cox2) of A. suum originated from Tibetan pigs at high altitudes in Tibet.

Exome sequencing in a family segregating for celiac disease

Celiac disease is a multifactorial disorder caused by an unknown number of genetic factors interacting with an environmental factor. Hence, most patients are singletons and large families segregating with celiac disease are rare. We report on a three-generation family with six patients in which the inheritance pattern is consistent with an autosomal dominant model. To date, 27 loci explain up to 40% of the heritable disease risk. We hypothesized that part of the missing heritability is because of low frequency or rare variants. Such causal variants could be more prominent in multigeneration families where private mutations might co-segregate with the disease. They can be identified by linkage analysis combined with whole exome sequencing. We found three linkage regions on 4q32.3-4q33, 8q24.13-8q24.21 and 10q23.1-10q23.32 that segregate with celiac disease in this family. We performed exome sequencing on two affected individuals to investigate the positional candidate regions and the remaining exome for causal nonsense variants. We identified 12 nonsense mutations with a low frequency (minor allele frequency <10%) present in both individuals, but none mapped to the linkage regions. Two variants in the CSAG1 and KRT37 genes were present in all six affected individuals. Two nonsense variants in the MADD and GBGT1 genes were also present in 5 of 6 and 4 of 6 individuals, respectively; future studies should determine if any of these nonsense variants is causally related to celiac disease.

The influence of corticosterone on antizyme gene expression in early regenerating rat liver

BACKGROUND AND STUDY AIMS

Antizyme 1, a specific inhibitor of Ornithine decarboxylase (ODC), plays a critical role in cell proliferation. Little is known about the impact of glucocorticoid on antizyme expression in the regenerating liver. In this paper, the effect of corticosterone on the gene expression of antizyme 1 in early regenerating rat liver induced by partial hepatectomy (PH) was investigated.

MATERIALS AND METHODS

Bilateral adrenalectomies (ADX) were performed 3 days before PH. Corticosterone in sesame oil or sesame oil was injected sub-cutaneously to ADX rats. Antizyme 1 mRNA and protein levels as well as polyamine contents in the regenerating liver were determined by RT-PCR, Western blotting and HPLC, respectively.

RESULTS

Antizyme 1 protein content in the oil-treated ADX group decreased significantly at 5, 7 and 9 h after PH compared to control. Following corticosterone administration the content rose dose-dependently during the whole experiment. At 5 h post-PH, the protein levels in 10 and 40 mg/kg corticosterone-treated ADX rats increased by 66% and 148%, respectively, when compared with the control group. However, no significant changes in antizyme 1 mRNA levels were observed in oil-treated ADX rats or corticosterone-treated groups compared to control. Polyamine contents in oil-treated ADX rats were the highest among all groups at 5 and 9 h. Corticosterone treatment resulted in a dramatic decrease of polyamine contents at most of the time points investigated when compared with those in control rats.

CONCLUSIONS

Corticosterone treatment induces antizyme 1 protein synthesis in early regenerating rat liver. However, it has little effect on antizyme 1 gene transcription. (Acta gastroenterol. belg., 2011, 74, 289-294).

Use of fluorometry for monitoring and control of a bioreactor

A new fluorescent bioreactor monitoring probe-multiple excitation fluorometric system (MEFS)-has been developed. This probe was compared to the commercially available BioChem Technology FluroMeasure system (NADH probe). In this task the fluorescence behavior of three model fermentation systems, ethanol fermentation by Candida utilis, phenol fermentation by Pseudomonas putida, and glucose fermentation by Saccharomyces cerevisiae, were examined. The results indicated that the fluorescence intensity and behavior of various cellular fluorophors vary significantly between the different fermentation systems. Monitoring a fermentation process using only NAD(P)H fluorescence provided limited information. The NAD(P)H fluorescence was found not to be the best fluorescence signal for monitoring cell concentrations. The best way of monitoring a bioreactor by fluorometry may be to monitor several fluorophors in the whole culture broth simultaneously and to relate these fluorescence signals to various biological parameters.

Identification of differentially expressed genes in the growth plate of broiler chickens with thiram-induced tibial dyschondroplasia

Tibial dyschondroplasia (TD) is characterized by expansion of the proximal growth plates of the tibiotarsus that fail to form bone, lack blood vessels, and contain non-viable cells. Thiram (a carbamate pesticide), when fed to young broiler chicks, induces TD with high regularity and precision. We used this experimental model to understand the cause of the defects associated with TD by selecting and identifying the genes differentially expressed in the TD growth plate of broiler chickens. Broiler chicks at 7 days of age were randomly divided into two groups. After fasting overnight, they were fed with regular diet (control) or the same diet containing 100 mg/kg thiram for 96 h to induce TD (thiram-fed). mRNA was purified from the growth plates of control and thiram-fed broilers. Forward and reverse-subtracted cDNA libraries were generated by suppression subtractive hybridization technology. Ten selected genes from cDNA libraries were identified by real-time quantitative polymerase chain reaction. All were differentially expressed in TD growth plates (P<0.05 or P<0.01). The levels of collagen type X (Col X), pro-alpha-1 collagen type I (Col I alpha1), collagen type IX (Col IX), NADH dehydrogenase (NADH DH), cytochrome C oxidase subunit III (COX III), enolase 1, alpha (ENO1), carbonic anhydrase II (CA2) and heat shock protein 90 (Hsp90) mRNA transcripts were up-regulated, while the expression levels of Matrilin 3 (MATN3) and chondromodulin-I (ChM-I) were down-regulated. Col I and Hsp90 were detected by immunohistochemistry at different stages. Given that these genes are involved in matrix formation, endochondral ossification, developmental regulation, electron transport in the mitochondrial respiratory chain and vascularization, our findings may provide new insights into understanding the pathogenesis of TD.

Lithium chloride preconditioning optimizes skeletal myoblast functions for cellular cardiomyoplasty in vitro via glycogen synthase kinase-3beta/beta-catenin signaling

The benefits of skeletal myoblast (SkM) transplantation for cardiomyoplasty are limited due to their decreased functional integration with host cardiomyocytes and the poor survival of implanted cells in ischemic hearts. However, little success has been achieved with respect to the strategies aiming to improve the efficiency of SkM transplantation. In this study, we demonstrated that LiCl-preconditioned SkMs resulted in significantly increased connexin 43 (Cx43) expression and gap-junctional communication with cardiomyocytes. Vascular endothelial growth factor (VEGF) expression of SkMs was significantly upregulated in response to LiCl. Furthermore, hydrogen peroxide induced SkM apoptosis and increased caspase-3 expression, whereas LiCl inhibited SkM apoptosis, resulted in the decrease of caspase-3 expression and promoted SkM proliferation. These effects of LiCl were mediated by inactivating glycogen synthase kinase-3beta (GSK-3beta), stabilizing the effector protein beta-catenin and translocating it into the nucleus of SkMs, confirming that LiCl mimics canonical Wnt signaling. These findings suggest that LiCl preconditioning may be a novel strategy to optimize SkM function for cellular cardiomyoplasty in vitro.

Changes of CSF and spinal pathomorphology after high-concentration ozone injection into the subarachnoid space: an experimental study in pigs

BACKGROUND AND PURPOSE

Our aim was to explore the changes of CSF and spinal pathomorphology after high-concentration ozone injection into a pig's subarachnoid space.

MATERIALS AND METHODS

Eight experimental pigs were randomly divided into 4 groups (n=2 in each group). In groups A, B, C, and D, animals were sacrificed for pathology 1 day, 1 week, 1 month, and 3 months after the injection, respectively. Ozone (10 mL, 90 microg/mL) was injected along the lumbar 4-5 interspace into the subarachnoid space with a 21-ga Chiba needle under fluoroscopy. CSF collection and CT and MR imaging were performed before injection and 30 minutes, 1 week, 1 month, and 3 months after injection, respectively. The spinal cords were observed macroscopically and microscopically.

RESULTS

No serious behavior abnormalities were observed in any animals. There were no abnormalities in CSF and spinal cords pathologically and radiologically after injection.

CONCLUSION

Our initial study suggests that high-concentration ozone injection into a pig's subarachnoid space will not cause serious sequelae such as chemical arachnoiditis and necrosis of the spinal cord, and this finding provides evidence of the safety of ozone inadvertently injected into subarachnoid space in the clinical treatment of disk herniation.

Cytokine release from osteoblasts in response to ultrasound stimulation

Bone is a dynamic tissue with a well-balanced homeostasis preserved by both formation and resorption of bone. Normal turnover of bone, however, can be upset by either increased osteoclast activity or decreased osteoblast function; either mechanism alone or both may result in a net loss of bone. Both osteoclasts and osteoblasts could be stimulated by mechanical stimulation in vitro, and it is assumed that this process may occur in vivo as well. In this experiment, we investigated this hypothesis by examining the effects of ultrasound stimulation on osteoblast growth and cytokine release. With this model, we explored the mechanism of low-intensity pulsed ultrasound on osteoblasts growth and upregulation of osteoclasts formation and function by cytokine release. The results showed that specific pulsed ultrasound exposure could enhance osteoblasts population together with increase in TGFbeta1 secretion and decrease in concentration of IL-6 and TNFalpha in the culture medium. Although, animal studies and clinical trial are needed to understand the real process in the whole body, ultrasound stimulation might be a good method for prevention of bone loss due to osteoporosis.

Purification and characterization of White Spot syndrome virus (WSSV) produced in an alternate host: crayfish, Cambarus clarkii

Penaeid shrimp is the natural host of White Spot Syndrome Virus (WSSV) that can cause high mortality in the infected hosts. Attempts to obtain sufficient amounts of purified intact WSSV for characterization have been unsuccessful. Using crayfish, Cambarus clarkii as a proliferation system, a large amount of infectious WSSV was reproduced and intact WSSV viral particles were purified with a new isolation medium by ultra-centrifugation. Purified WSSV particles were very sensitive to organic solvents and the detergent, Triton X-100. The size of the rod-shape, somewhat elliptical, intact WSSV was 110-130x260-350 nm with a long, tail-like envelope extension. The naked viral nucleocapsid was about 80x350 nm, and it possessed 15 spiral and cylindrical helices composed of 14 globular capsomers along its long axis, and a 'ring' structure at one terminus. Distinct WSSV genome DNA patterns were obtained when the purified genomic dsDNA of WSSV was digested with five different restriction enzymes (HindIII, XhoI, BamHI, SalI, and SacI). In addition, at least 13 major and distinct protein bands could be observed when purified intact WSSV viruses were separated by SDS-PAGE followed by Coomassie Brilliant R-250 staining. The estimated molecular weights of these proteins were 190, 84, 75, 69, 68, 58, 52, 44, 28, 27.5, 23, 19, and 16 kD, respectively. Both the 44 and 190 kD proteins were easily removed if the hemolymph from the WSSV infected crayfish was transiently treated with 1% Triton X-100 before it was subjected to gradient centrifugation, indicating that both of them are located on the surface of the viral envelope. These characteristics are consistent with WSSV isolated from the penaeid shrimp.

Factors predicting the age when type 2 diabetes is diagnosed in Hong Kong Chinese subjects

OBJECTIVE

To examine the factors predicting age at diagnosis of type 2 diabetes in Hong Kong Chinese.

RESEARCH DESIGN AND METHODS

The relationships between age at diagnosis and parental history of diabetes as well as an array of clinical and metabolic factors were examined using a hospital clinic-based diabetes registry involving 3,414 index patients with type 2 diabetes Patterns of age at diagnosis in successive generations were also examined using 21 affected child-parent pairs and 7 affected child-parent-grandparent trios.

RESULTS

Approximately 29% of the index patients were diagnosed with type 2 diabetes at < or = 35 years of age (hereby defined as early-onset). Compared with the patients diagnosed at >35 years of age (hereby defined as late-onset) the early-onset patients had higher rates of positive paternal (16 vs. 5%) and maternal (22 vs. 12%) history of diabetes (both at P < 0.01) and had poorer metabolic profiles. In the overall index patients, male sex, higher HbA1c waist-to-hip ratio (WHR), and systolic blood pressure (sBP); lower HDL cholesterol level; and a positive paternal was well as maternal history of diabetes predicted younger age at diagnosis. More senior age and higher BMI and diastolic blood pressure predicted olderq age at diagnosis. Predictors for younger age at diagnosis in the male patients were higher HbA1c and sBP and a positive paternal history of diabetes Predictors for younger age at diagnosis in the female patients were higher HbA1c WHR, and sBP and a paternal as well as maternal history of diabetes. In the affected child parent pairs and clild-parent-grandparent trios there was a decrease in age at diagnosis in successive generations.

CONCLUSIONS

Our data indicate that both familial (possibly genetic) and metabolic factors affect the age of onset of type 2 diabetes in the Chinese population. The results also suggest an onset and progression pattern of the disease that is compatible with the phenomenon of anticipation.

The islet amyloid polypeptide (amylin) gene S20G mutation in Chinese subjects: evidence for associations with type 2 diabetes and cholesterol levels

BACKGROUND AND OBJECTIVES

There has been evidence that the S20G mutation in the islet amyloid polypeptide (amylin) gene may be associated with type 2 diabetes. In the present study, we investigated the distribution of the mutation in Hong Kong Chinese, and examined whether there was evidence for associations between the mutation and type 2 diabetes and/or metabolic profiles.

SUBJECTS AND METHODS

This study involved 227 early and 235 late-onset (defined as onset age < or = 40 and > 40 years, respectively) type 2 diabetic patients, as well as 126 nondiabetic subjects. The mutation was detected using a PCR-RFLP method.

RESULTS

We identified six (2.6%) and one (0.4%) patients heterozygous for the mutation from the early and late-onset groups, respectively (P = 0.05). None of the nondiabetic subjects had the mutation. Insulin deficiency and poor glycaemic control were not common findings amongst carriers of the mutation. In the early onset group, the patients with the mutation had lower plasma levels of total (4.3 +/- 0.9 mmol/l vs. 5.3 +/- 1.1 mmol/l, P = 0.02) and low density lipoprotein (LDL)-cholesterol (2.3 +/- 0.7 mmol/l vs. 3.2 +/- 0.9 mmol/l, P = 0.01) than those without the mutation.

CONCLUSIONS

Our data suggest that the islet amyloid polypeptide gene mutation might be associated with early occurrence of type 2 diabetes and lower plasma levels of total and low density lipoprotein-cholesterol in the Chinese population.

Familial early-onset type 2 diabetes in Chinese patients: obesity and genetics have more significant roles than autoimmunity

OBJECTIVE

We examined the prevalence of different forms of diabetes in Hong Kong Chinese patients with familial early-onset type 2 diabetes and compared their clinical features with patients with familial late-onset type 2 diabetes.

RESEARCH DESIGN AND METHODS

A total of 145 young patients with early-onset diabetes (age and age at diagnosis < or = 40 years) and a family history of diabetes were studied. They were screened for mutations in the genes encoding glucokinase, hepatocyte nuclear factor (HNF)-4alpha, and HNF-1alpha. The mitochondrial DNA A-->G at nucleotide 3243 (mt3243) and amyLin S20G mutations were studied, and antibodies to GAD (anti-GADs) were also examined.

RESULTS

The prevalence of putative diabetogenic gene mutations and autoimmune markers were 4% for glucokinase, 0% for HNF-4alpha, 5% for HNF-1alpha, 3% for mt3243, 2% for amylin 520G, and 4% for anti-GAD. Compared with late-onset patients, the patients with early-onset diabetes had a higher prevalence of a parental history of diabetes and were generally more obese. When classified by obesity indexes (BMI and waist circumference), the obese patients, especially those with early-onset diabetes, had a clustering of cardiovascular risk factors and increased rates of retinopathy and albuminuria. CONCLUSIONS; Genetic factors (up to 14%) and obesity (55%) play more significant roles than autoimmunity (4%) in familial type 2 diabetes in young Chinese patients. The significance of obesity-related genes and other gene-gene and gene-environment interactions in these young patients remains to be determined.

Diabetes in Hong Kong Chinese: evidence for familial clustering and parental effects

OBJECTIVE

To investigate transmission patterns of diabetes and their relationships with clinical characteristics in Hong Kong Chinese patients with late-onset (age > or =35 years) type 2 diabetes.

RESEARCH DESIGN AND METHODS

This study involved 2,310 patients consecutively selected from a hospital clinic-based diabetes registry. These patients all reported the diabetes status of their parents as well as siblings.

RESULTS

Approximately 36% of the 2,310 patients reported at least 1 affected parent or sibling (25 and 21% reported at least 1 diabetic parent and sibling, respectively). These patients, irrespective of their sex, were more likely to have a diabetic mother than a diabetic father (17 vs. 13% of the male patients and 18 vs. 9% of the female patients, P<0.01). The male patients were more likely than the female patients to have a diabetic father (13 vs. 9%, P<0.01). The female patients with a diabetic mother were found to have higher levels of plasma total cholesterol compared with the female patients with a diabetic father in multiple comparisons with adjustment for significance (5.56+/-1.30 vs. 5.09+/-0.95 mmol/l, P<0.05). In 2-group comparisons, there was also evidence that the male patients with a diabetic father had higher BMI values than the male patients with a diabetic mother (25.9+/-3.5 vs. 25.0+/-3.5 kg/m2, P<0.05).

CONCLUSIONS

We found familial clustering of diabetes in the Hong Kong Chinese population as well as a significant maternal influence and a male sex-specific paternal effect. We suggest that both maternal and paternal factors may be implicated in the development of type 2 diabetes in the Chinese population.

Treatment of Chinese acromegaly with a combination of bromocriptine and octreotide

BACKGROUND

Good results have been reported with combined use of octreotide and bromocriptine in acromegalic Caucasians. Data concerning the efficacy and tolerability of this combination treatment in Chinese acromegalic patients are scanty.

AIM

The aim of this study was to assess the efficacy and tolerability of combined therapy using bromocriptine and octreotide in the treatment of acromegaly in Chinese patients and to compare the cost-effectiveness of various regimes.

METHODS

Sixteen Chinese acromegalic patients with growth hormone (GH) concentration not suppressible to below 5 mU/L (2 microg/L) during an extended OGTT were recruited to undergo four phases of the study. During the study period, the patients were given bromocriptine alone, bromocriptine and low dose octreotide, bromocriptine and medium dose octreotide, and medium dose octreotide alone. Plasma concentrations of GH and insulin-like growth factor-1 (IGF-1) were measured before and after the completion of each phase.

RESULTS

The number of patients reaching target GH concentrations was significantly higher when treated with octreotide compared to baseline (p<0.05). Bromocriptine alone had a significant effect but not to the extent of octreotide alone. A combination of low dose octreotide and bromocriptine is as efficacious in the treatment of acromegaly as high dose octreotide. None of the patients suffered from serious adverse effects.

CONCLUSION

The results confirmed the usefulness and tolerability of bromocriptine and octreotide in Chinese acromegalics. The most cost-effective regime in this study was a combination of low dose octreotide and bromocriptine.

Mitochondrial DNA A3243G mutation in patients with early- or late-onset type 2 diabetes mellitus in Hong Kong Chinese

BACKGROUND AND OBJECTIVES

The mitochondrial DNA A to G mutation at nucleotide 3243 (mt3243) is associated with a subtype of diabetes characterized by maternal transmission and deafness. We have previously reported a 2.7% prevalence of this mutation in a cohort of young patients with either type 1 or type 2 diabetes. In this study, we aimed to confirm this finding by examining for the prevalence of this mutation in a large-scale study.

SUBJECTS AND METHODS

Nine hundred and six unrelated Chinese patients with type 2 diabetes and 213 nondiabetic controls were studied. The presence of mt3243 mutation was determined by polymerase chain reaction amplification and ApaI digestion.

RESULTS

This mutation was found in four of 133 (3.0%) patients with early onset (</= 40 years) diabetes who also had a positive maternal family history, and in one of 348 (0.3%) patients with late-onset (> 40 years) diabetes and no family history. Basal pancreatic beta-cell function, as assessed by fasting plasma C-peptide, was variable amongst mutation carriers, and did not correlate with the level of heteroplasmy of mutation.

CONCLUSIONS

In agreement with most studies, our results suggest that despite the high prevalence of positive maternal family history of diabetes amongst our type 2 diabetic patients, mt3243 mutation was not a major cause of diabetes in either early- or late-onset diabetic patients in Hong Kong. The role of other genetic, environmental and intrauterine factors needs further investigation.

Young Chinese adults with new onset of diabetic ketoacidosis--clinical course, autoimmune status and progression of pancreatic beta-cell function

AIMS

To examine the clinical course, autoimmune status and pancreatic beta cell function, over a 2-year period, in young Chinese subjects newly presenting with diabetic ketoacidosis (DKA).

METHODS

A prospective study involving 562 out of 27,893 patients who were admitted to the medical ward with a principal diagnosis of diabetes mellitus during the recruitment period of 1 year.

RESULTS

Of these 562 patients, 27 were aged less than 35 years and admitted with a diagnosis of DKA and 11 (six males and five females) of these were newly diagnosed. Antibodies to glutamic acid decarboxylase (GAD) were present in five patients. Anti-ICA 512 was not detected in any of the patients. Basal and post-glucagon stimulated plasma C-peptide remained in the insulin-deficient range although showing improvement at 2 years.

CONCLUSIONS

These findings confirm the relative rarity of autoimmune Type 1 diabetes in young Chinese. Even when the clinical presentation takes the extreme form of acute DKA, less than 50% have positive autoimmune markers.

Glycaemic control in type 2 diabetes: the impact of body weight, beta-cell function and patient education

We examined the determinants of glycaemic control in a consecutive cohort of 562 newly-referred Chinese type 2 diabetic patients (57% women) during a 12-month period. All patients underwent a structured assessment with documentation of clinical and biochemical characteristics. Pancreatic beta-cell function was assessed by fasting plasma C-peptide concentration. Insulin deficiency was defined as fasting plasma C-peptide <0.2 pmol/ml. Insulin resistance (IR) was calculated using the homeostasis model assessment (HOMA) based on a product of fasting plasma glucose and insulin concentrations. Treatment was considered appropriate when insulin-deficient patients were treated with insulin and non-insulin-deficient patients were treated with oral agents or diet. Mean (+/-SD) age was 54.3+/-13.8 years (range 17-87 years) and disease duration was 5.0+/-5.9 years. At the time of referral, 70.5% (n=396) were on drug therapy (9% on insulin and 62.8% on oral agents), 20.6% (n=116) were on diet and 9% (n=50) had not received any form of treatment. The mean HbA(lc) was 8.4+/-2.3%. The geometric mean (x// antilog SD) of IR was 4.62x//2.51 (range 0. 63-162.7) and correlated only with waist : hip ratio (WHR, p=0.008). The geometric mean of plasma C peptide was 0.47x//2.89 nmol/l and correlated with BMI (p<0.001). Glycated haemoglobin was correlated positively with age (p=0.013), disease duration (p<0.001), IR (p<0. 001) and negatively with BMI (p<0.001). Glycated haemoglobin was lower in patients who had seen a dietitian (7.9% vs. 8.7%, p<0.001) or diabetes nurse (7.8% vs. 8.7%, p<0.001) or who performed self blood glucose monitoring (7.9% vs. 8.6%, p=0.001) and higher among smokers (8.9% vs. 8.2%, p=0.003). Compared to insulin-deficient patients (n=118), non-insulin-deficient patients (n=413) had features resembling that of the Metabolic Syndrome with increased WHR (p=0.005), blood pressure (p<0.001), BMI (p=0.001) and were older (p=0.04). Amongst the insulin-deficient patients, 27% were treated with oral agents or diet. Patients receiving appropriate therapy (n=362) had a lower HbA(lc) than those treated inappropriately (n=173) (8.2% vs. 8.7%, p=0.02). On multivariate analysis, short disease duration (p<0.001), low IR (p<0.001), high BMI (p=0.001), diabetes education (p<0.001), lack of smoking (p=0. 014) and choice of appropriate treatment (p=0.009) were the independent determinants of good glycaemic control.

Spontaneous necrosis of parathyroid adenoma: biochemical and imaging follow-up for two years

We report a patient with a biochemically and radiologically confirmed parathyroid adenoma, which underwent spontaneous resolution by necrosis. The patient was followed-up over the subsequent two years during which time the tumour and hypercalcaemia recurred. Sequential radiological and biochemical changes at the time of diagnosis, spontaneous necrosis and recurrence are documented fully.

Molecular genetics of diabetes mellitus in Chinese subjects: identification of mutations in glucokinase and hepatocyte nuclear factor-1alpha genes in patients with early-onset type 2 diabetes mellitus/MODY

AIMS

To examine the prevalence of identified MODY-related genes in Chinese subjects with early onset Type 2 diabetes mellitus and a positive family history of diabetes and to look for possible associations between the gene mutations and the development of diabetes.

METHODS

Ninety-two unrelated Chinese subjects with diabetes diagnosed before the age of 40 years who had a positive family history of diabetes were screened for mutations in hepatocyte nuclear factors (HNF-1alpha and HNF-4alpha) and glucokinase genes by direct sequencing. The family members of patients with mutations and 100 healthy controls were also examined.

RESULTS

Mutations in the HNF-1alpha and the glucokinase genes were found in 5% and 3% of the diabetic subjects, respectively but no mutations were found in the coding region of the HNF-4alpha gene. Three mutations found in the glucokinase gene were novel missense mutations (I110T, A119D and G385V). The mutations in the HNF-1alpha gene were also new and included four missense mutations (G20R, R203H, S432C, I618M) and one splice acceptor site mutation (IVS2nt-1G-->A). Patients with mutations in these genes were clinically heterogeneous with respect to phenotype and basal pancreatic beta cell function.

CONCLUSIONS

Genetic factors such as mutations in the HNF-1alpha and glucokinase genes may be important in the development of diabetes in Chinese people, especially when the disease is of early onset.

Plasma insulin, growth hormone, cortisol, and central obesity among young Chinese type 2 diabetic patients

OBJECTIVE

To examine the relationships between central obesity, insulin resistance index, plasma insulin, growth hormone (GH), and cortisol concentrations in 90 young Chinese type 2 diabetic patients (aged 33+/-5 years) and 104 age- and sex-matched control subjects (aged 32+/-9 years).

RESEARCH DESIGN AND METHODS

Young Chinese diabetic patients (aged <40 years) were recruited from the Prince of Wales Hospital. Blood pressure, height, weight, and waist and hip circumferences were determined. Venous blood was sampled for measurements of fasting plasma glucose, HbA1c, lipids, creatinine, insulin, GH, and cortisol. A 24-h urine was assayed for urinary albumin excretion (UAE). General and central obesity was represented by BMI and waist circumference, respectively. Insulin resistance index was estimated as a product of fasting plasma insulin and glucose concentrations.

RESULTS

Compared with control subjects, diabetic patients were more obese, hyperglycemic, and had worse lipid profile, higher blood pressures, UAE, insulin resistance index, plasma insulin, and cortisol concentrations (all P < 0.001) but lower GH concentrations (P < 0.05). When analyzed as a whole group (n = 194), increasing quartiles of waist circumference were associated with increasing trends of insulin resistance index, plasma insulin, and cortisol concentrations (all P < 0.01) but a decreasing trend of plasma GH concentration (P < 0.05). Using stepwise multiple regression analysis, waist circumference was only associated with sex variable (being higher in men) in the control subjects. In the diabetic group, 51% of waist circumference was independently related to male sex and increased plasma insulin and cortisol concentrations as well as reduced plasma GH levels.

CONCLUSIONS

In young Chinese type 2 diabetic patients, hyperinsulinemia, hypercortisolemia, and reduced plasma GH levels were closely associated with central obesity. Based on these findings, we postulate that maladaptive hormonal responses to rapid changes in lifestyle may have led to obesity and type 2 diabetes in these young patients. Alternatively, lifestyle-related obesity may have given rise to these hormonal changes. More studies are required to delineate the nature of these relationships.

A heterogeneously structured composite based on poly(lactic-co-glycolic acid) microspheres and poly(vinyl alcohol) hydrogel nanoparticles for long-term protein drug delivery

PURPOSE

To prepare a heterogeneously structured composite based on poly (lactic-co-glycolic acid) (PLGA) microspheres and poly(vinyl alcohol) (PVA) hydrogel nanoparticles for long-term protein drug delivery.

METHODS

A heterogeneously structured composite in the form of PLGA microspheres containing PVA nanoparticles was prepared and named as PLGA-PVA composite microspheres. A model protein drug, bovine serum albumin (BSA), was encapsulated in the PVA nanoparticles first. The BSA-containing PVA nanoparticles was then loaded in the PLGA microspheres by using a phase separation method. The protein-containing PLGA-PVA composite microspheres were characterized with regard to morphology, size and size distribution, BSA loading efficiency, in vitro BSA release, and BSA stability.

RESULTS

The protein-containing PLGA-PVA composite microspheres possessed spherical shape and nonporous surface. The PLGA-PVA composite microspheres had normal or Gaussian size distribution. The particle size ranged from 71.5 microm to 282.7 microm. The average diameter of the composite microspheres was 180 microm. The PLGA-PVA composite microspheres could release the protein (BSA) for two months. The protein stability study showed that BSA was protected during the composite microsphere preparation and stabilized inside the PLGA-PVA composite microspheres.

CONCLUSIONS

The protein-containing PLGA-PVA composite may be suitable for long-term protein drug delivery.

Comparative DNA cross-linking by activated pyrrolizidine alkaloids

The toxicity and bioactivity of pyrrolizidine alkaloids (PAs), common constituents of hundreds of plant species, and in herbal remedies and folk medicines prepared thereof, are probably due to their ability to form DNA cross-linking. We investigated DNA cross-linking activity by chemically-activated PAs from four different structural classes in Madin-Darby bovine kidney (MDBK) cells and in pBR322 DNA. In cell culture, alpha,beta-unsaturated macrocyclic diester pyrroles dehydrosenecionine (DHSN), dehydroriddelliine (DHRD) and the saturated macrocyclic diester pyrrole dehydromonocrotaline (DHMO) were significantly more potent cross-linkers than the simple necine base (retronecine) and an N-oxide (indicine N-oxide; INO) as determined by alkaline elution. The proportion of total DNA cross-links that were proteinase K-resistant (DNA-DNA cross-links) induced by the various pyrroles ranged from 0.08 (DHRN) to 0.67 (DHSN). Those pyrroles that were potent cross-linkers of cellular DNA also cross-linked, in a dose-dependent manner, Bam HI-digested pBR322 DNA as assessed by a gel retardation assay. The possible functional relevance of pyrrole-DNA cross-links was determined by their ability to interrupt PCR amplification of a 1.129 kb segment of pBR322. Dehydrosenecionine completely inhibited amplification, while DHMO was of intermediate potency, while DHRN and INO had no effect. Taken together, these studies suggest that structural features, most notably the presence of a macrocyclic diester, confer potent cross-link activity to PAs. In any event, DNA-DNA cross-linking is probably biologically relevant as indicated by their interference with DNA replication.

Poly(vinyl alcohol) nanoparticles prepared by freezing-thawing process for protein/peptide drug delivery

Poly(vinyl alcohol) (PVA) hydrogel nanoparticles have been prepared by using a water-in-oil emulsion technology plus cyclic freezing-thawing process. The PVA hydrogel nanoparticles prepared by this method are suitable for protein/peptide drug delivery since formation of the hydrogel does not require crosslinking agents or other adjuvants and does not involve any residual monomer. Particularly, there is no emulsifier involved in this new method. Bovine serum albumin (BSA), as a model protein drug, is incorporated into the PVA hydrogel nanoparticles. The PVA hydrogel nanoparticles possess a skewed or log-normal size distribution. The average diameter of the PVA hydrogel nanoparticles is 675.5+/-42.7 nm. Protein drug loading efficiency in the PVA hydrogel nanoparticles is 96.2+/-3.8%. The PVA hydrogel nanoparticles swell in an aqueous solution and the swelling degree increases with the increase of temperature. In vitro release studies show that the BSA release from the nanoparticles can be prolonged to 30 h. The BSA release follows a diffusion-controlled mechanism. The number of freezing-thawing cycle and release temperature both influence BSA release rate considerably. Less freezing-thawing cycle or higher release temperature leads to faster drug release. The BSA is stable during preparation of the PVA hydrogel nanoparticles.

Antibodies to glutamic acid decarboxylase in young Chinese diabetic patients

Antibodies to glutamic acid decarboxylase (GAD) are a useful autoimmune marker for type 1 diabetes mellitus in Caucasians. We examined antibodies to GAD and their relationships with clinical features and pancreatic beta cell function in 140 young Chinese diabetic patients. Over an 18-month period beginning in 1995, 140 young Chinese diabetic subjects with age of onset of disease < or = 35 years and age < 40 years were recruited consecutively, irrespective of their modes of presentation. Clinical features, antibodies to GAD and pancreatic beta cell function (using a glucagon stimulation test) were examined. Increased levels of antibodies to GAD (> 18 units) were detected in 12.1% (n = 17) of these subjects. Forty-three (31%) patients had a classical type 1 presentation and 65 (46%) patients were insulin-deficient based on post-glucagon plasma C-peptide levels. Patients who were insulin-deficient and had a type 1 presentation had the highest prevalence of antibodies to GAD (29.0%) compared with patients who had a type 2 presentation and were non-insulin deficient (6.4%, P = 0.003). Patients who had antibodies to GAD had lower body mass index and waist-hip ratio, earlier onset of disease, lower blood pressure, plasma triglyceride and C-peptide, and higher concentrations of plasma high-density lipoprotein cholesterol and glycated haemoglobin, and were more likely to require drug treatment, compared with those without antibodies to GAD. In conclusion, there was a low prevalence of antibodies to GAD in Chinese young diabetic patients although such antibodies remained a relatively specific marker for insulin deficiency and acute presentation. Causes other than autoimmunity should be sought to explain the high prevalence of insulin deficiency in these young Chinese patients.

Adrenal and hypophyseal non-Hodgkin's lymphoma presenting with panhypopituitarism

We report a case of non-Hodgkin's lymphoma presenting as anterior pituitary failure and found to have involvement of two endocrine glands, the pituitary and the adrenals.

Beta-adrenergic stimulation of reperfused myocardium after 2-hour ischemia

Postischemic myocardium possesses considerable contractile and metabolic reserves, but their mobilization could result in increased cell death. We tested the hypothesis that beta-adrenergic stimulation of reperfused myocardium would increase segment work more than O2 consumption, thereby improving efficiency without increased cell death. In 16 open-chest anesthetized dogs, the left anterior descending coronary artery (LAD) was ligated for 2 h; during the reperfusion period, isoproterenol (ISO; 0.1 microg/kg/min, i.v.) was administered to nine of the animals. Regional myocardial segment length and force were measured in the anterior (LAD) and posterior circumflex coronary artery (CFX) regions of the left ventricular myocardium. Work was calculated as the integrated products of force and shortening for each region. Regional myocardial O2 consumption was obtained from LAD flow and arterial and local venous O2 saturations. Infarct size (tetrazolium) was measured in the treated and untreated hearts at the end of the experiment. In untreated hearts, the first derivative of left ventricular pressure, cardiac output, and external work were significantly depressed during reperfusion; ISO restored all values to preocclusion levels. Regional myocardial work in both LAD and CFX regions was significantly increased by ISO (from 564 +/- 207 to 1,635 +/- 543 g/mm/min in LAD, and from 753 +/- 90 to 1,426 +/- 245 g/mm/min in CFX). Efficiency (work/oxygen consumption) of the reperfused region was similarly increased. LAD flow was significantly increased by ISO, and O2 extraction was unchanged. Infarct size was 28.2 +/- 4.7% in untreated hearts and 29.0 +/- 3.5% in ISO hearts. Thus isoproterenol stimulation significantly improved both regional and global function without subsequent evidence of increased cell death.

Combined use of a fasting plasma glucose concentration and HbA1c or fructosamine predicts the likelihood of having diabetes in high-risk subjects

OBJECTIVE

To assess the validity of using fasting plasma glucose (FPG) concentrations in conjunction with HbA1c or fructosamine for the screening of diabetes in high-risk individuals.

RESEARCH DESIGN AND METHODS

In this study 2,877 Hong Kong Chinese (565 [19.6%] men; 2,312 [80.4%] women) with various risk factors for glucose intolerance underwent a 75-g oral glucose tolerance test (OGTT) for screening of diabetes. The risk factors included a family history positive for diabetes, a history of gestational diabetes or impaired glucose tolerance, and obesity.

RESULTS

Using World Health Organization (WHO) criteria, 1,593 (55.4%) had normal glucose tolerance, 657 (22.8%) had impaired glucose tolerance, and 627 (21.8%) had diabetes. When the 1997 American Diabetes Association (ADA) criteria were applied, 394 (13.7%) had diabetes with an FPG > or = 7.0 mmol/l. Using multiple receiver operating characteristic curve analysis, the paired values of an FPG of 5.6 mmol/l and a HbA1c of 5.5% gave an optimal sensitivity of 83.8% and specificity of 83.6% to predict a 2-h plasma glucose (PG) > or = 11.1 mmol/l. Likewise, the paired values of an FPG of 5.4 mmol/l and a fructosamine level of 235 mumol/l (n = 2,408) gave an optimal sensitivity of 81.5% and specificity of 83.2%. An FPG > or = 5.6 mmol/l and an HbA1c > or = 5.5% was 5.4-fold more likely to occur in diabetic subjects (based on the WHO criteria) compared with nondiabetic subjects. For paired parameters less than these values, the likelihood ratio of this occurring in diabetic subjects was only 0.11. Similarly, an FPG > or = 5.4 mmol/l and a fructosamine > or = 235 mumol/l was fivefold more likely to occur in diabetic subjects than in nondiabetic subjects, with both parameters less than these values having a likelihood ratio of 0.04. Using these paired values as initial screening tests, only subjects who had an FPG > or = 5.6 mmol/l and < 7.8 mmol/l and an HbA1c > or = 5.5% (n = 642) required an OGTT to confirm diabetes, thereby saving 77.7% [(2,877-642)/2,877] of the OGTTs performed. Similarly, only subjects who had an FPG > or = 5.4 mmol/l and < 7.8 mmol/l and a fructosamine > or = 235 mumol/l (n = 526) required OGTT to confirm diabetes, meaning that 78.2% [(2,408-526)/2,408] of the OGTTs could have been saved. Based on the 1997 ADA criterion of an FPG cutoff value of 7.0 mmol/l, the corresponding numbers of OGTTs to be saved were 82.6% and 85.5%, respectively.

CONCLUSIONS

The paired values of FPG and HbA1c or FPG and fructosamine helped to identify potentially diabetic subjects, the diagnosis of which could be further confirmed by the 75-g OGTT. Using this approach approximately 80% of OGTTs could have been saved, depending on the diagnostic cutoff value of FPG.

A new description of arterial function: the compliance-pressure loop

Hypertension and atherosclerosis are associated with reduced arterial compliance, which is the principal component that reflects the dynamic behavior of the arterial system. Hence, change in arterial compliance has been used as a compass of arterial wall properties, as well as an effective parameter for assessing therapeutic treatment efficacy. The arterial compliance-blood pressure loop concept is introduced here for assessment of arterial function. Aortic pressure and flow were measured in experimental dogs during normal and acute hypertension. The compliance-pressure loops were constructed from pulsatile blood pressure waveforms and the corresponding compliances. The features of the loop are that, for any given heart beat, arterial compliance is seen to be maximal in early systole to facilitate ventricular ejection, compliance decreasing during the remainder of systole owing to increased blood pressure and reduced aortic flow, compliance in diastole increasing as pressure declines. The arteries are stiffer with reduced compliance in hypertension. Thus, the compliance-pressure loop can provide an effective characterization of the dynamic behavior of the arterial system in terms of pressure-flow relation and blood vessel properties.

Glycated haemoglobin and cardiovascular risk factors in Chinese subjects with normal glucose tolerance

Increased plasma glucose concentration is a predictive factor for mortality in both diabetic and non-diabetic subjects. Although glycated haemoglobin (HbA1c) is a useful index of mean blood glucose concentrations over the preceding 1 to 3 months, there are few data regarding its relationship to cardiovascular risk. We have examined the relationship between HbA1c and cardiovascular risk factors in 1280 subjects with normal glucose tolerance. Based on HbA1c tertiles (tertile 1: n = 427, 262 men and 165 women, HbA1c level: 2.9-4.7% in men and 3.2-4.2% in women; tertile 2: n = 426, 261 men and 165 women, HbA1c level: 4.7-5.1% in men and 4.2-4.6% in women; tertile 3: n = 427, 262 men and 165 women, HbA1c level: 5.1-6.7% in men and 4.6-6.9% in women), increasing HbA1c was associated with increasing age, blood pressure, waist-hip ratio, fasting and 2-h plasma glucose, 2-h insulin, cholesterol, low-density lipoprotein cholesterol, apolipoprotein B and urate concentrations. When age and sex were included as covariates, increasing HbA1c remained associated with increasing fasting and 2-h plasma glucose, 2-h insulin, total cholesterol, and low-density lipoprotein cholesterol concentrations. These findings emphasize the importance of hyperglycaemia, as reflected by HbA1c, as a continuum in the evaluation of cardiovascular risk. Furthermore, these findings support the hypothesis that cardiovascular disease risk commences with rising glucose concentrations before 'conventionally-defined' glucose intolerance occurs.

Gelatin nanoencapsulation of protein/peptide drugs using an emulsifier-free emulsion method

The nanoencapsulation of a model protein drug, bovine serum albumin (BSA), using gelatin as the matrix material is reported. Nanoencapsulation was conducted using a modified water-in-oil (w/o) emulsion method, which is emulsifier-free and simple. The nanoencapsulation product, BSA-containing gelatin nanoparticles, is characterized in terms of nanoparticle morphology, size and size distribution, water content, and in vitro protein release. The BSA-containing gelatin nanoparticles obtained from this nanoencapsulation process are nearly spherical and have a log-normal size distribution. The average diameter of the BSA-containing gelatin nanoparticles is approximately 840 nm. They can absorb 51-72% of water. In vitro release experiments demonstrate that BSA has been successfully encapsulated in, and can be released from the gelatin nanoparticles. The release of BSA from the gelatin nanoparticulate matrix follows a diffusion-controlled release mechanism. It is found that temperature affects both the water content and the BSA release rate of the gelatin nanoparticles.

Clozapine: a mimicry of phaeochromocytoma

OBJECTIVE

To report a case of clozapine-induced hypertension with raised urinary catecholamines.

CLINICAL PICTURE

A 27-year-old man fulfilling DSM-III-R criteria for catatonic schizophrenia was treated with clozapine. He later developed both hypertension and raised urinary catecholamines which mimicked phaeochromocytoma.

TREATMENT

Clozapine was withdrawn.

OUTCOME

Both blood pressure and urinary catecholamines normalised.

CONCLUSIONS

Clozapine may induce sympathetic hyperactivity.

Simple anthropometric indexes and cardiovascular risk factors in Chinese

OBJECTIVE

Obesity is a major public health problem due to its associations with multiple cardiovascular risk factors. Although there are sophisticated methods, such as imaging, to document total body fat and its distributions, anthropometric measurements remain important in clinical practice. We examined the relationships between cardiovascular risk factors and the three commonest anthropometric measurements for obesity, body mass index (BMI), waist-hip ratio (WHR) and waist circumference (WC), in Hong Kong Chinese subjects.

DESIGN AND SETTING

The data are obtained from a prevalence survey for glucose intolerance and lipid abnormality in a representative Hong Kong Chinese working population. All employees from a public utility company and a regional hospital were invited to participate.

SUBJECTS

There were 1513 subjects (910 men and 603 women, mean age +/- s.e.m.: 37.5 +/- 0.2 y). All of them had no significant past medical history.

MEASUREMENTS

BMI, WHR and WC of the 1513 subjects were assessed for their relationships with various cardiovascular risk factors. These include blood pressure, fasting and 2 h plasma glucose and insulin, glycated haemoglobin, total cholesterol, triglyceride, high density and low density lipoprotein cholesterol, and urine albumin concentration.

RESULTS

After age adjustment, all three anthropometric indexes were significantly correlated with the major cardiovascular risk factors in both men and women. When BMI, WHR and WC were analysed according to quartiles, there was a significant trend for blood pressure, plasma triglyceride, fasting and 2 h plasma glucose and insulin to increase, and high density lipoprotein cholesterol to decrease, with increasing obesity after adjustment for age and smoking. Using stepwise regression analysis with the three indexes as independent variables, most of the variance in blood pressure, plasma lipid, insulin, glucose and urinary albumin concentration were explained either by WC or WHR. In women, BMI was the main explanatory variable for reduced high density lipoprotein cholesterol.

CONCLUSIONS

In Hong Kong Chinese, BMI, WHR and WC provide important information in assessing cardiovascular risks. In men, central adiposity as reflected by WC and to some extent, WHR, explained most of the variance in blood pressure, plasma glucose, lipid, insulin and albuminuria. In women, all three indexes reflecting general and central obesity contribute to the variance in these risk factors.

Computer modeling of the effects of aortic valve stenosis and arterial system afterload on left ventricular hypertrophy

The degree of left ventricular hypertrophy is generally thought to reflect the severity of aortic stenosis. However, the compounded influence of arterial system load is poorly understood. We developed a computer model to investigate the effects of aortic valve stenosis in combination with various systemic arterial parameters in the development of left ventricular hypertrophy. Data show that an increased peripheral resistance and/or aortic valve resistance, results in an increase in left ventricular wall thickness and mass, while peak systolic wall stress remains constant. Changing arterial compliance to above normal level would not induce significant changes in wall thickness, while reduction in arterial compliance below normal would cause an increase in ventricular wall thickness. When a double load is imposed on the left ventricle by way of a stenotic valve and an increased arterial afterload, a greater and an aggregated increase in wall thickness results, hastening the hypertrophic process.

The effect of age on cardiovascular risk factors in Chinese women

Chinese women traditionally have a low incidence of coronary heart disease. However, information on cardiovascular risk factors in this population are relatively scarce. We examined these risk factors in 601 Hong Kong Chinese women (age+/-SEM, 38.5+/-0.4 years; range, 18-66 years) stratified into four age groups (group 1, < or =30 years; group 2, 31-40 years; group 3, 41-50 years; group 4, > or =51 years). Increasing age in Chinese women was associated with increased body mass index, waist-to-hip ratio, systolic and diastolic blood pressure, fasting plasma total cholesterol, triglyceride, low-density lipoprotein, apolipoprotein B, fasting and 2-h plasma glucose, glycated haemoglobin, fasting plasma insulin and urate concentrations. After adjustment for body mass index, waist-to-hip ratio and smoking, all these age-related associations remained statistically significant except for fasting plasma insulin concentration. There was a progressive increase with age in the prevalence of glucose intolerance, hypertension, dyslipidaemia and obesity. These prevalence rates further increased in subjects aged 51 years (the mean menopausal age in Asian women) or above. These findings suggest that age had an important and independent effect on cardiovascular risk in Chinese women and that, as in Caucasians, the onset of menopause might further increase this risk.