Stress-induced cervical lesions: review of advances in the past 10 years

The accumulation of experimental and clinical evidence during the past decade has significantly contributed to the understanding of the role of occlusally generated tensile stress in the etiology of certain noncarious cervical lesions of teeth. More important, this knowledge has led to the understanding of the reasons why traditional restorative treatments of these stress-induced cervical lesions fail. The case of failure can be attributed to the occlusally generated stresses that are concentrated at the cervical region and result in debonding, leakage, retention failure, and, ultimately, restorative failure. With the new understanding, restorative approaches that combine chemical adhesion and restorative materials of appropriate elastic properties show promise of long-term success.

The phenotype and phagocytic activity of macrophages during maedi-visna virus infection

Macrophages from maedi-visna virus (MVV) infected sheep have been shown to have an activated phenotype from sites of lesions in vivo. Here we have looked at the direct effect of virus infection on macrophage phenotype and activity in vitro by flow cytometry. There was no significant difference in the expression of several surface markers (CD4, CD8, MHC Class I, MHC Class II, lymphocyte function associated antigen(LFA)-1 and LFA-3) on monocyte-derived macrophages (MDM) by 5 days post MVV infection. In contrast the phagocytic activity of MVV-infected MDM for the yeast Candida utilis and erythrocytes was decreased by 5 days p.i. although the surface binding of erythrocytes was not affected. Interestingly, an activated phenotype was seen on alveolar macrophages (AM) from sheep with maedi (surface expression of MHC Class I, Class II and LFA-1 was increased), but there was no difference in the binding and phagocytosis of erythrocytes by these cells. However the binding and phagocytosis of the bacterium, Pasteurella hemolytica was increased with AM from MVV-infected sheep without lesions. Similarly there was no significant difference in the phagocytic and erythrocyte rosetting activity between fresh monocytes from MVV-infected and uninfected control sheep. Therefore the phenotype of macrophages taken from sites of lesions caused by MVV does not correspond to a direct effect by the virus on these cells or to particular activities of the macrophages.

An epidemiological study of food poisoning in Korea and Japan

The purpose of this study was to make a comparative epidemiological observation on outbreaks of food poisoning between Korea and Japan, during the period from 1971 to 1990. The mean morbidity rate by fiscal year from 1971 to 1990 was 3.0 per 100,000 population in Korea, and 29.2 in Japan. The mean mortality rate, in Korea was 2.48%, and in Japan, 0.07%. When both morbidity and mortality rates in Korea and Japan were compared during same period, the morbidity rate in Japan was much higher than that in Korea. However, the mortality rate of patients in Korea was much higher than that in Japan. Comparison of food poisoning rates according to food preparation facilities in Korea and Japan was also performed; outbreaks in Korea most frequently involved home-made foods (48% of the total cases), while in Japan, restaurants accorded for 32.7%. Foods most commonly incriminated in Korea were seafood, meat and animal products, grains and vegetables, including mushrooms. In Japan, however, unknown causes, followed by seafood, vegetables, and meat and animal products were the most common. Food poisoning of bacterial origin in Korea was 58.6% of the total case, including Vibrio spp. (37.6%), Salmonella spp. (23.1%), Staphylococcus spp. (14.9%), pathogenic E. coli (6.8%) Clostridium spp. (0.5%) and other species (17.1%). In Japan, the majority of bacterial causes were Vibrio spp. (47.3%), Staphylococcus spp. (24.6%), Salmonella spp. (14.8%), E. coli (3.5%), Clostridium spp. (0.2%) and other species (9.6%). In conclusion, the outbreaks of food poisoning in Korea and Japan may be mainly caused by food handling, and their occurrence may be different according to food sources.

The mitochondria are recognition organelles of cell stress

The cellular response to stress includes synthesis of specific stress proteins in the presence of a generalized suppression of protein synthesis. The response occurs in intact animals, individually stressed organs of intact animals, donor organs upon removal, regardless of preservation methods, and cells in culture. The molecular biology of stress protein induction is not understood. While stress proteins are beneficial, overall suppression of protein synthesis, if prolonged, is harmful. Since altered energy metabolism is integral to stress induction, we examined the mitochondria to determine if they could provide a possible molecular mechanism for initiating the response. Rat myoblasts were incubated at varying temperatures for up to 120 min in [35 S] methionine. Proteins were separated electrophoretically and newly synthesized proteins visualized autoradiographically. Isolated mitochondria from resting rat myoblasts were then stressed, label incorporation determined, and newly synthesized protein was visualized. Stress sharply suppressed protein synthesis in mitochondria but autoradiograms of stressed mitochondria showed that a single stress protein of 18 kDa was synthesized. Mitochondria independently respond to stress and synthesize a stress protein from their own DNA. This protein may provide an intermediary pathway that links stressful conditions in the environment to the overall response observed in the cell.

Estimating life expectancy using an age-cohort model in Taiwan

OBJECTIVES

Life expectation is a valuable summary index in public health and actuarial science. The life expectancies published in the vital statistics, however, are derived from the "current" rather than from the "cohort" life table. The former is based on a strong assumption of constant mortality in the population, whereas the latter calls for a recording of the mortality experience of a group of individuals, which is often an impossible task. Thus, a method of calculating cohort life expectancy without actual follow up is much needed.

METHODS

Estimation of cohort life expectancy was based on an age-cohort model. Mortality data for the male population in Taiwan from 1951 to 1990 are used to illustrate the methodology.

RESULTS

The increment of life expectancy over time in Taiwan is actually steeper than was previously thought using the current life table technique.

CONCLUSIONS

The method is easy to implement and the data required are the usual age and period cross classified mortality data. It warrants further investigation.

An audit of prophylactic antibiotic treatment following tonsillectomy in children

A prospective audit study was undertaken to assess the effect of two different management policies following tonsillectomy in children in this hospital, one of which requires a prophylactic five-day course of oral antibiotics and the other doses not. A total of 95 children were entered into the trial: 54 received post-operative antibiotics and 41 did not. The post-operative recovery was assessed by completion of a parent questionnaire which included the following parameters: degree of patient distress, nausea and vomiting, otalgia, halitosis, pharyngeal bleeding, analgesic requirement, day of return to a regular diet and General Practitioner consultation. There was no significant reduction in any of the morbidity measures in patients treated with antibiotics. I fact, the analgesic requirement and the incidence of otalgia and irritability on Days 6 and 7 and secondary haemorrhage were significantly higher in the antibiotic-treated patients. Although the number of patients included in this study are small, the result suggest that post-operative antibiotics do not improve the outcome of uncomplicated tonsillectomy. Our previous practice of routinely administering antibiotics to post-tonsillectomy children has been discontinued as the consequence of this audit.

Analysis of seasonal data using the Lorenz curve and the associated Gini index

BACKGROUND

Epidemiological inferences about the aetiology of a disease can often be made from its seasonal patterns. However, due to its multifactorial nature, the seasonality component can be obscured by other factors. It is therefore important to develop statistical techniques which are sensitive to minute temporal changes.

METHODS

The Lorenz curve and the associated Gini index are applied for characterizing and testing seasonal variations. Computer simulations were conducted to compare the powers of the Gini test and other seasonality tests. We also show that the Gini index can itself be interpreted as a probability related to temporal clustering.

RESULTS

The powers of the proposed tests are shown to be higher than or at least comparable to other tests under various conditions.

CONCLUSIONS

Though computer-demanding, the proposed method is well-suited for analysing seasonal data.

Electron microscope studies of the replication of a British isolate of maedi visna virus in macrophages and skin cell lines

The replication of EV1, a British isolate of maedi visna virus (MVV), in macrophages has not previously been studied. We therefore used transmission and scanning electron microscopy (TEM and SEM respectively) to compare the replication of EV1 in macrophages versus skin cell lines. Monocyte-derived macrophages (MDM), alveolar macrophages (AM) and skin cell lines were all permissive for replication by EV1. Virus grew rapidly and to high titers in skin cell lines and mature MDM. However replication was slower in less mature MDM or AM. Virion budding occurred through (i) cytoplasmic membranes only (skin cells), (ii) cytoplasmic and vesicular membranes (MDM) or (iii) vesicular membranes only (AM). This meant that virions accumulated in vacuoles within macrophages. Retroviral intracytoplasmic type A particles were seen in the cytoplasm of AM and MDM infected with strain EV1, but not MDM infected with strain 1514 (an Icelandic MVV strain) and were shown to contain MVV gag antigen by immunogold staining.

Autoregressive age-period-cohort models

Age-period-cohort analysis of vital data has received much attention recently, and it is already well known that the exact linear relation of the three time factors creates a non-identifiability problem. Previous studies have shown that the curvature terms of these factors are estimable but the linear trends are not. However, little attention has been paid to the possibility that the effects due to cohort and/or period might change through time stochastically rather than deterministically and hence display a stochastic trend. In this paper, we model the cohort effects as an AR(1) process and use lung cancer mortality data from 1966 to 1990 for males in Taiwan as an example. The parameters are identifiable in the proposed model and the estimates are found to be stable. However, the assumption made in the model should be carefully considered before using our methodology.

Complications of paediatric tonsillectomy post-discharge

A post-operative survey of 291 children was conducted to assess morbidity found at home in the first five days post-tonsillectomy. Analgesic requirement (92.4 per cent), signs of distress (90.4 per cent), otalgia (69.1 per cent), halitosis (66.7 per cent) were common. Physical or behavioural changes (36.8 per cent) and secondary haemorrhage (8.9 per cent) were also prominent features. Nausea was reported in 59 children (20.3 per cent) and delayed return to a normal diet which in turn predisposed to secondary haemorrhage. Return to normal diet was independent of pain. General Practitioners were consulted by 60.6 per cent and more than half were prescribed drugs. The presence of an organized clot in the tonsillar fossa (3.45 per cent) post-operatively did not delay discharge from hospital and none of these patients re-presented with secondary haemorrhage. Based on their child's experience in this study, only one third of the parents approved of day-case tonsillectomy in principle, a finding which has implications for the instigation of day-case tonsillectomy procedures.

Should nasopharyngeal biopsy be mandatory in adult unilateral glue ear?

Unilateral secretory otitis media is a recognized presenting feature of nasopharyngeal neoplasia. In the two cases presented, biopsy from the nasopharynx revealed an unsuspected underlying adenocarcinoma. The need to biopsy the normal looking post-nasal space is highlighted.

A novel tree-structured analysis for non-invasive diagnosis of gastric adenocarcinoma

Non-invasive diagnosis of gastric adenocarcinoma (GAC) is usually difficult due to the low sensitivity and specificity of serologic markers,including pepsinogens and gastrin. For the improvement of the diagnostic values of these markers, a "recursive partitioning and amalgamation" algorithm was employed to construct a decision protocol. A total of 636 subjects including 161 healthy subjects, 163 patients with GAC, 196 with gastric ulcer and 116 with duodenal ulcer were enrolled. Serum levels of gastrin, pepsinogen I, pepsinogen II, and the ratio of pepsinogen I / pepsinogen II were determined for each of the subjects. The proposed "decision tree" classifies subjects into five subgroups with different risks of GAC and peptic ulcer, based on the information of age, serum pepsinogen and gastrin levels. Using this novel analysis system, an expected probability of GAC or ulcers could be obtained. Patients with an age > 62 years and a serum level of pepsinogen I < or = 33 ng/ml were strongly indicated for further confirmatory tests of GAC. This treestructured analysis is also helpful in clarifying the interactions between various serologic markers and demographic factors.

Clinicopathologic characteristics of Helicobacter pyloric seropositive gastric adenocarcinomas

To compare and characterize retrospectively the clinicopathologic features of gastric cancers with and without previous Helicobacter pylori infection, we determined the preoperative seropositivity of H. pylori in 151 patients who had undergone gastric resection for primary gastric adenocarcinoma between 1988 and 1993. The overall seroprevalence of H. pylori was 60.9%. H. pylori-positive gastric cancers were frequently associated (p<0.05) with macroscopic localized types (Borrmann I and II) in which negative cancer associated with infiltrative types (Borrmann III and IV) and cancer invasion of the duodenum. Multivariate analysis showed that H. pylori seropositivity was not an independent prognostic factor. Pathologic tumor-node-metastases (TNM) stage remained the only prognostic indicator. Our study suggests that H. pylori has a significant impact on the clinically relevant tumor biology of gastric cancer. Investigation along this line is warranted.

Survival after resection of gastric cancer and prognostic relevance of systematic lymph node dissection: twenty years experience in Taiwan

A retrospective study of 954 resectable gastric cancers in a single institute of Taiwan from 1971 to 1990 was performed to evaluate improvements in gastric cancer surgery. The patients were divided into four time periods representing an overall experience of progressive implementation of aggressive resection and increased extent of systematic lymph node dissection. The clinicopathologic data and survival rates were statistically compared and the significance of the extent of resection on survival analyzed. A significant increase in the proportion of upper one-third tumors (from 14.8% to 20.4%) and a decrease in the incidence of intestinal type (73.6% to 41.5%) was found within the overall period. The proportion of patients with early gastric cancer increased from 11.5% to 19.4%. Patients who underwent total gastrectomy and combined visceral resection increased from 13.7% to 27.4% and 19.8% to 41.1%, respectively. An increase of both total dissected lymph node number and the incidence of detected lymph node metastases in early gastric cancer were associated with more extensive lymphadenectomy. An improved 5-year survival rate following aggressive resection was found for all stages except stage IV and T4 lesions, and the surgical mortality decreased from 5.5% to 2.0%. Patients with earlier stage lesions benefited more from radical resection, especially those with stage II and T2 lesions. Systematic lymph node dissection increased the 5-year survival of patients by about 10% for stage III or T3 lesions but not for patients with stage IV or T4 lesions. Multivariate analysis confirmed the significance of the improved technique of lymphadenectomy on the prognosis of gastric cancer following resection in Taiwan.(ABSTRACT TRUNCATED AT 250 WORDS)

Disability among the elderly of Taiwan

A cross-sectional study on the correlates of elderly disability was conducted in Taiwan. A total of 400 subjects was randomly selected according to Barthel Index scores from among 2600 subjects, which was a sample of a previous community-based health survey of elderly aged 65 or over. After comprehensive interviews and examinations of the subjects, disability dimensions and its correlates were identified. Results showed elderly with lower Mini-Mental State Examination scores and chronic diseases (such as stroke, pressure sores, hypertension, fracture, etc.) were more physical-functionally and socially disabled. This suggests that prevention and treatment of chronic diseases should be pursued further and that further assessment of cognitive-mental status in the elderly is warranted. In addition, males were more disabled than females in a physical-functional aspect, which may be the consequence of the traditional Chinese cultural effect.

Analysis of cancer rates using excess risk age-period-cohort models

BACKGROUND

Recently the age-period-cohort (APC) model has become a popular epidemiological tool. However, it is well known that the model suffers from the identifiability problem. The simple multiplicative formulation of the model in terms of the age, period, and cohort variables without resorting to the underlying biology also casts doubt on the interpretability of the model parameters.

METHODS

Excess risk APC models for cancers are developed based on carcinogenesis processes in human populations. These models have the beneficial feature of biological plausibility and do not suffer from the identifiability problem. Apart from the age, period, and cohort effects, a new kind of effect, the impact effect, is also introduced into the models. A computer program has been developed to fit the models which contain non-linear as well as restricted parameters.

RESULTS

Two published mortality datasets are used to demonstrate the methodology. The proposed models fit better than the conventional APC model in both examples.

CONCLUSIONS

Despite all the merits of the proposed models, several statistical issues should be investigated further before accepting this methodology as a general data-analytical tool.

Necrosis of the colon as a complication of cardiac injury: case report

Necrosis of the colon as a complication of cardiac injury is very rare. A 21-year-old young man was sent to the emergency room with shock status because of a stabbing wound penetrating into the heart. The patient survived after cardiopulmonary resuscitation, emergency sternotomy, and cardiac repair. Necrosis of the colon occurred 11 days after the accident.

Comparison between resectable gastric adenocarcinomas seropositive and seronegative for Helicobacter pylori

The preoperative seropositivity of Helicobacter pylori was determined in 128 patients who had undergone gastrectomy for primary gastric adenocarcinoma during the past 5 years. The overall seroprevalence of H. pylori was 64 per cent. Gastric cancers positive for H. pylori were associated with tumours located in the lower third of the stomach which were of localized type (Borrmann I and II) (P < 0.05), but not with age, sex, blood type, tumour size, invasion depth, lymph node metastases, histological type, DNA ploidy or type of surgery. The cumulative 5-year survival curves after surgical resection were significantly better in patients who were positive for H. pylori. Multivariate analysis revealed that seropositivity for H. pylori was not an independent prognostic factor. Pathological tumour node metastasis staging was the only prognostic indicator. Better prognosis for those with H. pylori-seropositive gastric cancer may be attributed to the more advanced stage of H. pylori-seronegative gastric cancers. The potential role of H. pylori in gastric cancer carcinogenesis and its biological significance warrant further investigation.

Surgical treatment of gastric adenocarcinoma: the role of lymph node dissection

In this retrospective study, 652 patients who had curative resections for gastric cancer from 1977 to 1991 were reviewed to evaluate improvements in gastric cancer surgery and the influence of the extent of lymphadenectomy on survival. The patients were grouped into three time periods: 1977 to 1981, 1982 to 1986 and 1987 to 1991. The percentage of patients with early gastric cancer increased from 17.7% during 1977 to 1981, to 24.3% during 1987 to 1991. The average number of dissected lymph nodes was 7.5 +/- 8.1 during 1977 to 1981 and 16.4 +/- 10.3 during 1987 to 1991, when more radical lymphadenectomy was adopted. Total gastrectomies increased from 10.9% to 25.9% in the same time periods while combined visceral resections increased from 26.7% to 38.1%. Operative mortality decreased from 5.0% to 1.7%. The overall 5-year survival rate increased from 34.8% to 59.4%. In subgroup analysis, significant improvement of the 5-year survival rate was noted in the following groups: patients with stage I, II and III tumors but not stage IV; both proximal and distally located tumors; tumors with or without lymph node metastases; T1 and T2 but not in T3 and T4 (cancer invasion beyond the serosa). The decreased surgical mortality in recent years suggests that curative resection with extensive lymph node dissection can now be safely performed. Radical gastrectomy with extended lymphadenectomy may be adopted in gastric cancer resection for better control of regional disease.

Diagnosis of gastric adenocarcinoma using a scoring system: combined assay of serological markers of Helicobacter pylori infection, pepsinogen I and gastrin

This study was carried out to develop a scoring system for the diagnosis of gastric adenocarcinoma (GAC). A total of 686 subjects, 150 patients with GAC, 182 with gastric ulcer, 127 with duodenal ulcer, and 227 subjects with negative findings, were enrolled. Analysis of the likelihood ratio (LR) showed that patients with advanced age, ulcer in the stomach, low serum levels of pepsinogen I (PGI), low PGI x gastrin values, and low PGI/gastrin ratio were likely to have GAC. Of these indicators, the serum PGI level had the greatest weight, with a LR of 7.59 for the group with a level < 30 ng/ml. A scoring system combining serum PGI level, Helicobacter pylori seropositivity, and gastric ulcer status was derived, using a logistic regression model. This scoring system was found to be better than any one-parameter criterion for diagnosing GAC after evaluation by the area under the receiver operating characteristic curve (0.84; 95% confidence interval, 0.81-0.88) or by specificity-fixed sensitivity (sensitivity 0.82 at specificity 0.72, sensitivity 0.87 at specificity 0.66, sensitivity 0.96 at specificity 0.44). This scoring system may be potentially useful as a new model for the noninvasive diagnosis of GAC in the future.

Age-period-cohort analysis of breast cancer mortality

The objective of this study is to develop a hypothesis about the carcinogenesis of breast cancer from a descriptive analysis. This study is an application of the age-period-cohort model (APC model) on the mortality rate of breast cancer in Taiwan over the period from 1964 to 1991. Age-specific and age-adjusted mortality rates are described and then age, period, and cohort effects are separately analysed. (Female) breast cancer mortality data in Taiwan from 1964 to 1991 were abstracted from the annual reports of the Taiwan Provincial Department of Health. The population data in Taiwan from 1964 to 1991 were abstracted from the demographic data in Taiwan compiled by the Ministry of Interior, R.O.C. The results show that both age-adjusted and age-specific mortality rates of breast cancer are increasing over the study period and with birth cohorts. The bimodal pattern becomes more apparent in later periods. The Clemmensen's hook is five years later both in the descriptive study and the APC analysis. The findings suggest a possible role of later life overnutrition as the major period effed (promoter) and a change in reproductive behavior as the cohort effect (initiator). The application of the APC model also denotes the possible role of later life overnutrition and a change in reproductive behavior after the birth cohort of 1929. These findings may help us develop hypotheses of carcinogenesis of breast cancer.

Hepatocellular carcinoma in a pregnant woman detected by routine screening of maternal alpha-fetoprotein

A 26-year-old pregnant woman was diagnosed as having hepatocellular carcinoma at 16 weeks of gestation when extremely high levels of alpha-fetoprotein were found on a routine screening examination. The pregnancy was terminated, and a right hepatectomy was performed. Although such cases are rare, this one suggests that early measurement of maternal serum alpha-fetoprotein in a pregnant woman with hepatitis B surface antigenemia may allow the timely detection of a hepatocellular carcinoma.

Cytotoxic activity against maedi-visna virus-infected macrophages

The cell type predominantly infected by maedi-visna virus (MVV) is the macrophage, and we have looked at the ability of MVV-infected macrophages to interact with cytotoxic T lymphocytes (CTL), important effector cells against virus infections. MVV-specific CTL precursors were detected, after in vitro culture with MVV antigen and recombinant human interleukin-2, in peripheral blood lymphocytes of all MVV-infected sheep. MVV-infected monocyte-derived macrophages and alveolar macrophages were able to stimulate CTL activity in vitro and were targets for these activated CTL. The major effector cell population using MVV-infected macrophage targets was CD8+ lymphocytes, although another population, lymphokine-activated killer cells, may also have been involved. There was no direct cytotoxic activity found in alveolar lymphocytes from MVV-infected sheep without lung lesions.

Exon 8 mutation of p53 gene associated with nodal metastasis in non-small-cell lung cancer

The epidemiologic characteristics of lung cancer in Taiwan differ from those in other parts of the world in low male-to-female ratio, the high percentage of adenocarcinoma, and the relatively high percentage of nonsmokers who are victims. To investigate possible correlation between p53 gene alteration and the unique characteristics of lung cancer here, p53 gene status of 36 patients with primary, resected non-small-cell lung cancer (NSCLC) was studied by directly sequencing the cDNA of the p53 gene, then acquiring clinical and pathologic data to correlate p53 gene status with clinical parameters and pathologic staging. Missense mutations were present in 42% (15 of 36) of patients with NSCLC, including 42% (10 of 24) with adenocarcinomas, and 45% (five of 11) with squamous cell carcinomas. The frequency of p53 mutation was 50% in smokers and 29% in nonsmokers (p = 0.355). The mutation occurred most frequently in exon 8 (56%), and G:C to A:T transitions in non-CpG or CpG sites were the most commonly observed base changes (56%). These findings differ from the high prevalence of G to T transversion found in previous reports. The frequency of metastasis in hilar and mediastinal lymph nodes was significantly higher in tumors with p53 mutations. The association with nodal stage was strong for mutations within exon 8, but it was less apparent for mutations in other exons probably because of the small number. This study suggests that p53 gene missense is common in NSCLC in Taiwan, but smoking is probably not the sole contributing factor. More interestingly, p53 gene mutations, especially those in exon 8, may be associated with regional nodal metastasis.

Predisposition to renal carcinoma in the Eker rat is determined by germ-line mutation of the tuberous sclerosis 2 (TSC2) gene

Genetic predisposition to neoplasia often involves tumor suppressor genes. One such model of hereditary renal carcinoma was described in the rat by Eker. These tumors share morphologic similarities with human renal cancer. Linkage analysis localized the inherited mutation to rat chromosome band 10q12. This region is syntenic with human chromosome band 16p13.3, the site of the tuberous sclerosis 2 (TSC2) gene. A specific rearrangement of the rat homologue of TSC2 was found to cosegregate with carriers of the predisposing mutation. Tumors with or without loss of heterozygosity expressed only the mutant allele, consistent with the two-hit hypothesis. This mutation gave rise to an aberrant transcript that deletes the 3' end normally containing a region of homology with the catalytic domain of rap1GAP.

p16 alterations and deletion mapping of 9p21-p22 in malignant mesothelioma

To determine whether p16 is altered in human malignant mesothelioma (MM), molecular analysis of multiple 9p loci was performed on 40 cell lines and 23 primary tumors from 42 MM patients. We identified homozygous deletions of p16 in 34 (85%) cell lines and a point mutation in 1 line. Down-regulation of p16 was observed in 4 of the remaining cell lines, 1 of which displayed a DNA rearrangement of p16. Homozygous deletions of p16 were identified in 5 of 23 (22%) primary tumors; no mutations or rearrangements were found in these specimens. Four cell lines displayed a single homozygous deletion proximal to or distal to p16; 4 others had 2 nonoverlapping deletions, one involving p16 and the other involving a region proximal to this locus. These data indicate that alterations of p16 are a common occurrence in MM cell lines and, to a lesser extent, in primary tumors. Furthermore, deletions of 9p21-p22 outside of the p16 locus may reflect the involvement of other putative tumor suppressor genes that could also contribute to the pathogenesis of some MMs.

Maternal role in type 2 diabetes mellitus: indirect evidence for a mitochondrial inheritance

BACKGROUND

The role of mitochondrial inheritance in type 2 diabetes mellitus has received much attention recently. In this study, three existing datasets in Taiwan are analysed to examine this theory.

METHODS

Two of the datasets were community surveys and one a hospital case series. Subjects who had information regarding their paternal or maternal diabetic status were selected for the present study. In the first dataset, 745 subjects had information about paternal diabetic status and 765 had information about maternal diabetic status. In the second dataset, 255 and 267 subjects had the paternal and maternal information, respectively. In the third, a total of 3625 subjects had information about both their paternal and maternal diabetic status. Diabetic status of the study subjects was determined by fasting plasma glucose levels and/or oral glucose tolerance test; their parental diabetic status was collected by interview.

RESULTS

The three datasets consistently demonstrated a significantly elevated odds ratio (OR) for reporting maternal diabetes (OR = 2.64, 95% confidence interval: 1.12-5.71) in diabetic patients as compared to non-diabetic subjects. The reporting of paternal diabetes, however, was not significantly different between diabetics and non-diabetics. In addition, the OR for reporting paternal diabetes were not significantly different between groups of different age-at-onset. With respect to maternal history, the OR increased significantly when age-at-onset was younger (test-for-trend P < 0.001).

CONCLUSIONS

Our findings support mitochondrial inheritance of type 2 diabetes mellitus in the human population. The age-modifying effect was also in accordance with the mitochondrial oxidative phosphorylation paradigm for degenerative diseases.

A novel dioxabicyclo[3.3.1]nonane, a key intermediate in the synthesis of erythronolide B seco-acid

In the title compound, (1R,4S,5R,6R,8R)-1-ethyl-4,6,8-trimethyl-2,9-dioxabicyclo[3.3.1]++ +nonan-6-yl 1-imidazolecarboxylate, C16H24N2O4, the 2,9-dioxabicyclo[3.3.1]nonane ring system assumes a double-chair conformation. Bond angles around the ring are enlarged compared to normal tetrahedral values to alleviate some of the overcrowding which results from close intramolecular H...H and C...C contacts. The N-imidazolylcarbonyloxy group is nearly planar with dihedral angles of 5.2 (2) and 6.0 (2) degrees between the imidazole and carbonyl groups for molecules 1 and 2, respectively.

Rupture of the diaphragm after blunt trauma

OBJECTIVE

To analyse our cases of acute rupture of the diaphragm after blunt trauma to find out how to diagnose it earlier and manage it more promptly in future.

DESIGN

Retrospective study of casenotes.

SETTING

Division of general surgery, district hospital, Taiwan.

PATIENTS

50 Patients who presented with acute rupture of the diaphragm after blunt trauma during the 10 year period 1982-91.

MAIN OUTCOME MEASURES

Morbidity and mortality.

RESULTS

The left hemidiaphragm was injured in 43 cases (86%), and the right in 7 (14%). The most common cause was road traffic accidents. 48 Patients had associated injuries, mainly to the chest and abdomen, and pelvic fractures. 44 Ruptured diaphragms were diagnosed before operation by chest radiography or upper gastrointestinal contrast examination. The transabdominal approach was the most appropriate, because 23 patients had intra-abdominal visceral injuries as well. 20 Patients (40%) had complications, and the rate was 33% among those treated within 24 hours and 70% among those whose treatment was delayed longer than 24 hours (p = 0.067). There were 3 deaths (6%); one patient died of empyema of the right chest as a result of simultaneous perforation of a hollow viscus. 6 Patients were permanently disabled by head and spinal injuries, and pelvic fractures.

CONCLUSION

The prognosis of repairing diaphragmatic hernias is good as the disability rate is low. The diagnosis should be kept in mind in all patients with chest injuries, pelvic fractures, or abdominal injuries with hypoxaemia, as this will result in earlier treatment and improve prognosis. The transabdominal approach is the most appropriate because it makes simultaneous abdominal injuries easier to treat. Correct operative management at an early stage will keep mortality to a minimum.

Age-period-cohort analysis of pulmonary tuberculosis mortality in Taiwan: 1961 to 1990

The specific aim of this study was to examine the effects of age, calendar period of death, and birth cohort in pulmonary tuberculosis (TB) mortality in Taiwan during the period 1961 to 1990. A log-linear Poisson regression model modified from the method of Osmond and Gardner was used and 79,881 deaths (58,025 males and 21,856 females) were included in the analysis. Birth cohort is the most significant predictor of pulmonary TB mortality according to the model. The earliest birth cohort from 1891 had a pulmonary TB mortality 17,327 and 6,186 times those born from 1986 for males and females, respectively. There was also a significant age effect. The youngest age group of zero to four years had a pulmonary TB mortality 7.10 and 5.87 times those for the age group of five to nine years for males and females, respectively. The oldest age group of 70 to 74 years had a risk of pulmonary TB mortality 2.89 and 1.88 times those for the five- to nine-year age groups for males and females, respectively. Parameters of the period factor showed a decreasing pulmonary TB mortality from 1961 to 1990 that was less significant than those of age or cohort. In addition to the improvement in medical measures that influenced the effect of calendar year on TB mortality, year of birth is an important determinant in the trend of TB mortality in Taiwan. The result shows that the major focus for TB mortality in Taiwan is in the age groups born between 1891 and 1921.

Autophosphorylation-dependent protein kinase phosphorylates Ser25, Ser38, Ser65, Ser71, and Ser411 in vimentin and thereby inhibits cytoskeletal intermediate filament assembly

The autophosphorylation-dependent protein kinase has been identified as a potent vimentin kinase that incorporates 2 mol of phosphates per mol of protein and generates five major phosphorylation sites in vimentin. Tryptic phosphopeptide mapping by high-performance liquid chromatography followed by sequential manual Edman degradation and direct peptide sequence analysis revealed that Ser-25, Ser-38, Ser-65, and Ser-71 in the amino-terminal domain and Ser-411 in the carboxyl-terminal domain are the phosphorylation sites in vimentin phosphorylated by this kinase, indicating that autophosphorylation-dependent protein kinase is a potent and unique vimentin kinase. Functional study further revealed that phosphorylation of vimentin by autophosphorylation-dependent protein kinase can completely inhibit polymerization and assembly of the cytoskeletal intermediate filament as demonstrated by electron microscopic analysis. Taken together, the results provide initial evidence that the autophosphorylation-dependent protein kinase may function as a vimentin kinase involved in the structure-function regulation of the cytoskeletal system. The results also support the notion that this cyclic nucleotide- and calcium-independent protein kinase may function as a multisubstrate/multifunctional protein kinase involved in the regulation of diverse cell functions.

Isolation of a new gene GS2 (DXS1283E) from a CpG island between STS and KAL1 on Xp22.3

A gene, GS2 (DXS1283E), was isolated from a CpG island located approximately midway between the steroid sulfatase (STS) and the Kallmann syndrome (KAL1) loci on the distal short arm of the human X chromosome. DNA sequencing of a GS2 cDNA clone revealed an open reading frame for a basic protein of 253 amino acid residues. A polymorphic CT dinucleotide repeat was found in the 3' untranslated region. The GS2 gene is expressed in all human tissues examined, including heart, brain, placenta, lung, liver, muscle, kidney, pancreas, and spleen. Several GS2 transcripts, ranging in size from 1.1 to 5.8 kb, were found among different tissues, suggesting tissue-specific processing of the GS2 transcript. Characterization of GS2 genomic clones revealed that the gene consists of 7 exons spanning over 26 kb, with a CpG island located in the first intron. The GS2 gene is transcribed toward Xpter, in the same direction as KAL1 but opposite to that of STS.

Bing-Neel syndrome or malignant external otitis in Waldenstrom's macroglobulinaemia?

Malignant external otitis is classically associated with insulin-dependent diabetes mellitus probably due to generalized systemic immunodeficiency (Mowet and Baum, 1971). A unique case of malignant external otitis associated with Waldenstrom's macroglobulinaemia is presented.