A double-blind comparison of once-daily metoprolol controlled-release and atenolol in the treatment of Chinese patients with mild to moderate hypertension

The efficacy and tolerability of controlled-release metoprolol (metoprolol CR/ZOK), 100-200 mg, and atenolol, 50-100 mg, once daily was compared in Chinese patients with mild to moderate essential hypertension. The study was of a randomized, double-blind, two-way crossover design. The active treatment periods lasted 4 weeks each and were preceded by a 4-week placebo run-in period. The two double-blind phases were separated by a 2-week washout period on placebo. Blood pressures and heart rates were measured at rest in each 2-week visit and during exercise at the end of each treatment period. Twenty-four patients (M/F = 14/10) were valid for efficacy analysis. Their ages ranged from 39 to 68, with a mean of 53.5 years. The rest supine blood pressure and heart rate before active treatment was 160 +/- 15/106 +/- 6 mmHg and 75 +/- 14 beats/min (mean +/- SD), respectively. A responder was defined as exhibiting a supine diastolic blood pressure < or = 90 mmHg or a supine diastolic blood pressure reduction of at least 10% of the baseline level. Both agents had high response rate: 88% and 92% of all patients responded to metoprolol CR/ZOK and atenolol, respectively. Both active treatments considerably reduced resting systolic and diastolic blood pressures and heart rates as compared with baseline (p < 0.001), respectively. With controlled-release metoprolol, a more pronounced beta 1 blockade was obtained than with atenolol, which was expressed as a significant reduction in exercise-induced heart rate at the highest comparable workload compared with placebo (p < 0.05). These findings are compatible with those reported from western populations.

Success of endoscopic injection therapy in correlation with maximal one-day transfusion requirement

BACKGROUND AND STUDY AIMS

The rate of blood transfusion is related to blood flow and the diameter of the bleeding vessel. Therapeutic endoscopy is less effective in larger vessels. To determine the effect of therapeutic endoscopy with pure ethanol injection in massive peptic ulcer bleeding, we conducted a retrospective study using the maximal one-day blood requirement as an indicator of the required blood transfusion.

PATIENTS AND METHODS

The maximal one-day blood requirement was defined as the total amount of blood transfusion needed within a day to keep hemodynamics stable and hemoglobin above 8.0 g% before therapeutic endoscopy. From January 1986 to May 1993, 283 patients with high-risk signs of the stigmata of hemorrhage on endoscopy, who received pure ethanol injection therapy, were included in this study. There were 214 men and 69 women with a mean age of 58.4 years (ranging from 16 to 93 years). One hundred forty-three had gastric ulcers; 125 had duodenal ulcers; and 15 had stomal ulcers. Patients whose maximal one-day blood requirement was less than 1000 ml were assigned to Group I. Patients without, and patients with, major organ diseases whose maximal one-day blood requirement was more than 1000 ml were assigned to Group IIa and Group IIb, respectively.

RESULTS

In Group I, 87.1% attained permanent hemostasis; 51.3% in Group IIa; and 49.4% in Group IIb. Temporary hemostasis and failure rates were 8.9% and 4.8% in Group I; 14.5% and 33.8% in Group IIa; and 21.2% and 29.4% in Group IIb. The rate of permanent hemostasis was significantly lower in patients with massive bleeding (p < 0.001) but did not differ between patients with and without major organ diseases (p > 0.05).

CONCLUSION

The success rate for pure ethanol injection therapy was lower in patients with a large maximal one-day blood transfusion requirement.

Gender role identity and perceptions of Ismaili Muslim men and women

Gender roles in the Ismaili Muslim community were examined. Eighty-one Shia Imami Nizari Ismaili Muslims living in Ontario, Canada, provided demographic data and completed the Bem Sex-Role Inventory (BSRI; Bem, 1981) and the Attitudes Toward Women Scale (AWS; Spence, Helmreich, & Stapp, 1973). The results indicated that, although the Muslim women had more liberal views about gender roles than the Muslim men did, both the men and the women reported views that were liberal and comparable to those that have been reported by other Canadian samples.

Central cardiovascular effects of CPU-23, a substituted tetrahydroisoquinoline, in rats

The cardiovascular effects of intracerebroventricular (i.c.v.) injections of low doses of CPU-23, a substituted tetrahydroisoquinoline, were investigated and compared with those of nifedipine in pentobarbital-anaesthetized Sprague-Dawley rats. CPU-23, in doses of 0.2 to 0.5 mg/kg (i.c.v.), which did not elicit any significant cardiovascular responses when injected intravenously, caused a clear-cut and long-lasting decrease of mean arterial pressure (MAP) and heart rate (HR) in a dose-dependent manner. The effects of CPU-23, in a dose of 0.05 mg/kg, were similar to those of nifedipine, a prototype L-type calcium antagonist. The hypotensive effects of CPU-23 were significantly attenuated by bilateral cervical vagotomy. The results strongly suggest that a central component may be involved in the cardiovascular effects of CPU-23 and that dihydropyridine receptor sites in the brain may be involved in the central control of cardiovascular functions.

Septic acute cholecystitis

BACKGROUND

Bacteremia occurs frequently in cholangitis, but the incidence of bacteremia in acute cholecystitis has not previously been examined.

METHODS

Seventy-eight cases (46 men and 32 women; mean age, 63 +/- 10 years) of acute cholecystitis with positive blood cultures were analyzed for clinical manifestation, bacteriology, and what consequences ensued. Seventy-eight non-bacteremic cholecystitis patients, matched for age and sex, served as the control group.

RESULTS

The prevalence of bacteremia in acute cholecystitis was 7.65% (78 of 1020). A single microorganism was isolated from the blood and bile in 87.2% and 27.3%, respectively. The commonest organisms were Escherichia coli and Klebsiella pneumoniae. The source of bacteremia could be identified from the infected bile in 80% of cases. Compared with the non-bacteremia group, significant increases in liver biochemical test results (aspartate and alanine aminotransferases and bilirubin, and so forth), more complications (acute renal failure and septic shock), and higher mortality (9.0%) were found in the bacteremic group.

CONCLUSION

Acute cholecystitis is not often complicated by bacteremia, but when bacteremia is present, morbidity and death more consistently ensue.

Complement-mediated neurotoxicity is regulated by homologous restriction

The ability of beta-amyloid peptides to activate the classical complement cascade and the presence of various complement proteins including the membrane attack complex (C5b-9) on dystrophic neurites in Alzheimer's disease brains, raises the possibility that the complement system may contribute to this neurodegenerative disorder. To address this issue, we have studied the effect of complement activation on nerve growth factor (NGF)-differentiated rat pheochromocytoma PC12 cells, and on retinoic acid (RA)-differentiated human neuroblastoma SH-SY5Y cells. Although incubation of both cell types with human serum resulted in activation of complement, as indicated by iC3b formation, only PC12 but not SH-SY5Y cells were killed by human serum treatment. In contrast, heat-inactivated serum (56 degrees C, 45 min) was not neurotoxic. On SH-SY5Y cells, both PCR amplification and immunocytochemistry demonstrated the presence of CD59, a glycosylphosphatidylinositol-anchored protein that restricts homologous complement activation by inhibiting the formation of the membrane attack complex. The presence of CD59 probably accounts for the inability of human complement to lyse the human cell lines. Indeed, removal of glycosylphosphatidylinositol (GPI)-anchored proteins with phosphatidylinositol-specific phospholipase C (PI-PLC) rendered SH-SY5Y cells vulnerable to complement attack and eventually led to serum-medicated cell death. Reconstituted C5b-9 was also toxic to both PC12 and PI-PLC-pretreated SH-SY5Y cells. These observations suggest that complement activation can cause neuronal cell death and that this process is regulated by homologous restriction.

Gastric leiomyosarcoma: a clinicopathological review

OBJECTIVE

To report our experience of eight patients with primary gastric leiomyosarcoma.

DESIGN

Retrospective study.

SETTING

Teaching hospital, Taiwan.

SUBJECTS

8 patients who presented with primary gastric leiomyosarcoma between 1986 and 1990.

MAIN OUTCOME MEASURES

Endoscopic, radiological, and histopathological features, DNA ploidy, and outcome.

RESULTS

Abdominal pain and gastrointestinal bleeding were the most common presenting symptoms. In 5 of the 7 patients who had endoscopy preoperatively a diagnosis of submucosal tumour was made, but a definite diagnosis of leiomyosarcoma was made in only 3. A provisional diagnosis of leiomyosarcoma was made in 3 of the 4 patients who had computed tomography. All patients underwent some form of gastric resection ranging from palliative resection to total gastrectomy. Patients in whom the tumour had invaded adjacent organs had a poor prognosis. Histopathological grading of tumours correlated well with DNA ploidy.

CONCLUSION

Both histopathological grading and DNA ploidy could be helpful objective prognostic criteria in patients with primary gastric leiomyosarcoma.

Total knee arthroplasty after patellectomy

We compared the outcome of total knee arthroplasty in 19 patients who had had previous patellectomy with the results in a matched series of arthroplasties performed on knees in which the patella was intact. The mean follow-up was 63 months (21 to 114). In the study group, the outcome was poor in five patients. There was instability in the coronal plane in three patients and persistent pain in four. Three supracondylar fractures occurred. The overall complication rate was 36%. In the control group, pain was relieved in every case and there were no complications. Total knee arthroplasty has a higher complication rate and inferior results if the knee has undergone prior patellectomy.

Total knee arthroplasty after patellectomy

We compared the outcome of total knee arthroplasty in 19 patients who had had previous patellectomy with the results in a matched series of arthroplasties performed on knees in which the patella was intact. The mean follow-up was 63 months (21 to 114). In the study group, the outcome was poor in five patients. There was instability in the coronal plane in three patients and persistent pain in four. Three supracondylar fractures occurred. The overall complication rate was 36%. In the control group, pain was relieved in every case and there were no complications. Total knee arthroplasty has a higher complication rate and inferior results if the knee has undergone prior patellectomy.

cAMP is not involved in interleukin-1-induced interleukin-6 release from human astrocytoma cells

We have previously shown that activation of the phosphatidyl-inositol/phospholipase C pathway could induce interleukin 6 (IL-6) release from U373MG human astrocytomes cells. We also found that, although interleukin 1 beta (IL-1 beta) did not activate phosphatidy-linositol turnover, it induced, a robust release of IL-6. In the present study, we examined the role of adenylate cyclase/cyclic 3',5'-adenosine monophosphate (cAMP) pathway in IL-6 release. Agents which mimicked (dibutyryl cAMP) or stimulated (isoproterenol and forskolin) cAMP formation were found to induce IL-6 release and their effects could be potentiated by 3-isobutyl-1-methylxanthine (IBMX), a phosphodiesterase inhibitor. On the other hand, in spite of its robust action on IL-6 release, IL-1 beta did not stimulate cAMP formation. Other possible signal transduction mechanisms involved in IL-1 beta-induced IL-6 release are discussed.

Regulation of the release of interleukin-6 from human astrocytoma cells

Recent evidence suggests that the level of interleukin-6 (IL-6) is elevated in Alzheimer's disease (AD) brains. IL-6 is produced by reactive glial cells and could potentially affect neuronal survival. Understanding the biochemical mechanism that regulates the production and release of IL-6 by astrocytic cells may help to identify potential targets for therapeutic intervention in AD. In the present study, glial fibrillary acidic protein-positive human U373MG astrocytoma cells were used as a model of reactive astrocytes. Production of IL-6 in response to drug treatment was monitored with an ELISA assay. Histamine (1-100 microM), substance P (SP; 1-100 nM), and human interleukin-1 beta (IL-1 beta; 1-30 pM) stimulated the release of IL-6 in a time- and concentration-dependent manner, with EC50 values of 4.5 microM, 8 nM, and 4.5 pM, respectively. The respective effects of histamine, SP, and IL-1 beta were effectively blocked by the histamine H1, SP, and IL-1 receptor antagonists, supporting a receptor-mediated event for these agents. Both histamine and SP enhanced the formation of inositol phosphates and increase intracellular calcium levels, suggesting that the phosphatidylinositol bisphosphate/protein kinase C pathway may be involved in the IL-6 release process. Indeed, phorbol 12-myristate 13-acetate, a protein kinase C activator, also evoked IL-6 release from the U373MG cells. On the other hand, IL-1 beta, which produces a much more robust release of IL-6 than histamine or SP, has no effect on inositol phosphate formation or intracellular calcium levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of sexual assault among women patients seen in family practice clinics

OBJECTIVE

This study assesses the prevalence and characteristics of sexual assault among women patients attending two family medicine residency training clinics.

METHODS

Two hundred four consecutive women patients 18 years and older were asked to complete a questionnaire; one hundred eighty-eight (92.2%) agreed.

RESULTS

Fifty-four (28.7%) of the 188 women patients reported some type of sexual assault. Approximately 15% of patients reported being victims of rape; 8% reported attempted rape, and 5.3% reported forced sexual contact. Twelve (41.4%) of the 29 rape victims indicated that they had been raped more than once. Only 24% of rape and attempted rape victims reported the incident to police, 18.2% sought medical attention, and 21% sought counseling.

CONCLUSIONS

Family physicians should be aware of the prevalence of sexual assault in their practices and should understand proper questioning, management, counseling, and referral of patients.

An abnormal umbilical artery waveform: a strong and independent predictor of adverse perinatal outcome in patients with preeclampsia

OBJECTIVE

An abnormal umbilical artery Doppler waveform is a risk factor for adverse perinatal outcome. However, it has not been established whether this is related to the earlier gestational age at delivery of fetuses with abnormal Doppler findings or whether Doppler findings are an independent predictor of perinatal outcome. Our purpose was to determine whether an abnormal Doppler umbilical artery waveform is associated with adverse perinatal outcome even after the gestational age at delivery is controlled for as a confounding variable in patients with preeclampsia.

STUDY DESIGN

Umbilical artery velocimetry studies were performed within 7 days of delivery in 72 consecutive patients admitted to our unit with preeclampsia. Adverse perinatal outcome was defined as fetal distress requiring cesarean delivery. Apgar score < 7 at 5 minutes, significant neonatal morbidity, or perinatal death. Significant neonatal morbidity was defined as neonatal sepsis, intraventricular hemorrhage (grade > or = 2), respiratory distress syndrome, pneumonia, bronchopulmonary dysplasia, acute renal failure, or necrotizing enterocolitis. Stepwise multiple logistic regression and receiver-operator characteristic curve analysis were used.

RESULTS

Patients with abnormal umbilical artery velocimetry had a significantly higher rate of complications, including cesarean section for fetal distress, preterm delivery, low Apgar scores, significant neonatal morbidity, and perinatal death, than did patients with a normal waveform. Receiver-operator characteristic curve and stepwise logistic regression analysis indicated that an abnormal umbilical artery waveform was a significant independent predictor for the development of adverse perinatal outcome (odds ratio 14.2, p < 0.005) after other confounding variables were adjusted.

CONCLUSION

An abnormal Doppler umbilical artery waveform is a strong and independent predictor of adverse perinatal outcome in patients with preeclampsia.

Changes in immunoglobulin levels in zinc-deficient mice infected with Trypanosoma musculi

A metabolic imbalance technique was used to study the effects of zinc deficiency on immunoglobulin levels in mice infected with Trypanosoma musculi or immunized with parasite products. Zinc-deficient mice developed higher numbers of parasitemia earlier and exhibited prolonged infection. Irrespective of the diet, higher IgG1, IgG2b, and IgM levels, lower IgG2a and IgA levels, and uniform IgG3 levels were exhibited primarily by mice infected with T musculi and to a lesser extent by mice immunized with parasite products. Zinc-deficient mice showed smaller increases in IgG1 and IgM, but larger gains in IgG2b compared with mice on full-complement and pair-fed diets. However, IgG2a decreased significantly in zinc-deficient mice.

Direct repeat sequences are not required at the breakpoints of age-associated mitochondrial DNA deletions in rhesus monkeys

The large majority of mitochondrial DNA (mtDNA) deletions analyzed from mitochondrial myopathies and aging humans have been found to be flanked by direct repeats, a finding which has led to the slip-replication hypothesis of deletion formation. In this study, we have characterized 13 mtDNA deletion breakpoints from skeletal muscle harvested from 9- to 27-year-old rhesus monkeys. Seven of the deletions, five of which were unique to a particular animal, did not have direct repeats at the deletion breakpoints. In contrast, two of the three deletions common to several animals had direct repeats flanking the breakpoints. It appears, therefore, that at least two different mechanisms exist by which mtDNA deletions are formed during aging, one requiring and one independent of flanking direct repeats. Furthermore, the species in which mtDNA deletions are detected may determine which mechanism predominates.

Role of Helicobacter pylori in cirrhotic patients with peptic ulcer. A serological study

Helicobacter pylori was found to be a promoter factor of peptic ulcer that has an incidence higher in patients with hepatic cirrhosis. To clarify the role between H. pylori and peptic ulcer in patients with hepatic cirrhosis, a serological test (ELISA test, HEL-p, AMRAD, Australia), was used to measure the presence of H. pylori of patients with hepatic cirrhosis. Within two years, 108 cirrhotic patients who had received a panendoscopic examination were enrolled in this study. There were 79 males and 27 females with a mean age of 53.2 years. Sixty-four cases had positive serum HBsAg and 44 had negative serum. The results showed that the prevalence of Helicobacter pylori in cirrhosis was 43.5% (47/108). There was no difference of HEL-p-positive rate between peptic ulcer and normal gastroduodenal mucosa (45.2% vs 46.1%, P > 0.05). According to this study, there appears to be no relation between peptic ulcer and H. pylori in patients with hepatic cirrhosis. The etiology of peptic ulcer in cirrhotic patients need further study.

Complement C1q does not bind monomeric beta-amyloid

The tendency of both labeled and unlabeled beta-amyloid to bind in solution to C1q, the recognition species in the complement cascade, was examined using both hydrodynamic and spectroscopic methods. Potential binding interactions were evaluated using a purified synthetic beta-amyloid 1-40 sequence, alone, and selectively labeled at the amino terminus with spectroscopic probes. The probes permitted both absorbance and fluorescence analyses of beta-amyloid binding interactions. Under conditions used for the analyses beta-amyloid exists exclusively as a monomer in solution, and C1q retains an intact quaternary structure and is capable of binding to IgM. When mixed together the monomeric beta-amyloid does not bind to, or interact with, the complement C1q at concentrations below approximately 100 microM. The data suggest that if beta-amyloid toxicity is associated with complement activation in Alzheimer's disease then monomeric beta-amyloid is likely not responsible for activation through the classical complement pathway.

The regulation of membrane 125I- and 86Rb+ permeability in a virally transformed cell line (NCL-SG3) derived from the human sweat gland epithelium

We have explored the factors that may regulate membrane permeability in a cell line (NCL-SG3) derived from the human sweat gland epithelium. Ionomycin increased the rate of 125I-efflux from preloaded cells and this action appeared to be due to an increase in intracellular free calcium ([Ca2+]i). The ionomycin-evoked increase in 125I- efflux was reduced in cells that were exposed either to barium or to valinomycin in the presence of a high concentration of external potassium. It thus appears that a fraction of the ionomycin-evoked increase in 125I- efflux is due to the activation of potassium channels and experiments using 86Rb+ also suggested that ionomycin increased the rate of potassium efflux, an effect which was totally abolished by barium. Blockade of Na(+)-K(+)-2Cl- cotransport and of Cl- -HCO3- exchange reduced the basal rate of 125I- efflux and the ionomycin-evoked increase in 125I-efflux from control cells and from cells depolarized by valinomycin. These transport systems thus contribute to anion efflux, although [Ca2+]i-dependent chloride channels also appear to be present. Acetylcholine increases [Ca2+]i in the secretory cells of human sweat glands, but this neurotransmitter did not increase [Ca2+]i in NCL-SG3 cells and so membrane permeability was not under cholinergic control. Adrenaline did not increase [Ca2+]i, but this hormone did evoke cyclic-3',5'-adenosine monophosphate (cyclic AMP) production. However, membrane permeability was not under adrenergic control, as the cells did not appear to express functional, cyclic AMP-dependent anion channels. This may be because they were not fully differentiated under the culture conditions. ATP consistently evoked a dose-dependent increase in anion efflux that appeared to be mediated by [Ca2+]i. The increase in [Ca2+]i was initiated by the release of calcium from a limited internal store and was subsequently sustained by calcium influx. UTP and ADP also increased [Ca2+]i, whereas adenosine, AMP and alpha,beta-methylene ATP were without effect. These data thus suggest that a subclass of type 2 purine receptor, which is functionally coupled to phosphoinositidase C, is present in these cells.

Fish oil supplementation attenuates free radical generation in short-term coronary occlusion-reperfusion in cholesterol-fed rabbits

We studied the changes in lipid peroxidation and prostanoid metabolism in short-term coronary occlusion-reperfusion in controls and those rabbits (11 in each group) fed a 1% high cholesterol diet with or without 10% fish oil supplementation for one week. Acute coronary occlusion for 10 minutes was induced by ligating the marginal branch of the left circumflex coronary artery. The vessels were then reperfused for 1 hour. The cholesterol and fish oil treated rabbits had the lowest malondialdehyde levels both in the ischemic and non-ischemic (normal) areas, the least increase of malondialdehyde level in the ischemic area, and the highest 6-keto-PGF1 alpha/thromboxane B2 ratio in the non-ischemic area after reperfusion among the 3 groups. These rabbits had the highest myocardial superoxide dismutase levels both in the ischemic and normal areas, and the least decrease of superoxide dismutase level in the ischemic area. These data suggest that rabbits fed a high cholesterol diet with fish oil supplementation had an attenuated lipid peroxidation, which reflected a reduced free radical generation during a short-term coronary occlusion followed by reperfusion.

Hydronephrosis accidentally detected by gastrointestinal sonography

A retrospective study was carried out on patients with gastrointestinal complaints, who were accidentally found to have varying degrees of hydronephrosis between October 1989 and April 1991. The criteria for hydronephrosis given by Ellenbogen et al were used for ultrasonographic diagnosis. Grade 0 and 1 were classified as mild degree and grade 2 and 3 as moderate and severe, respectively. The causes of hydronephrosis were determined by intravenous pyelography, retrograde pyelography, and/or computed tomography. Of 44 patients with hydronephrosis who had complete studies, 20 had a mild degree of hydronephrosis, 18 had a moderate degree, and 6 had a severe degree. All 24 patients with moderate and severe degrees of hydronephrosis had obstruction as the etiology, but only 50% of the cases with mild hydronephrosis were found to have pathological lesions. Urolithiasis (79.4%) was the most common cause of hydronephrosis in this study. Benign prostate hypertrophy, carcinomas, external compression, and tuberculosis followed. Hydronephrosis found accidentally by sonography in the patients with gastrointestinal complaints is significant.

Fiberoptic bronchoscopic Nd-YAG laser therapy in obstructive airway diseases

BACKGROUND

This study reports the results of Neodymium-Yttrium-Aluminum Garnet (Nd-YAG) laser resection on benign and malignant obstructing airway diseases which has been done in our hospital for four years. The effect of this treatment on patients' arterial blood gases, during and after the process is also analyzed. The benefit of adjuvant therapy with radiotherapy and/or chemotherapy after laser vaporization is discussed.

METHODS

Fiberoptic bronchoscopic Nd-YAG laser therapy was performed in 32 cases of lung cancer (primary 27, secondary 5) and 11 cases of benign tracheobronchial diseases with total or near total airway obstruction. The therapy was performed through the oral route under local anesthesia. The result of therapy was classified as "excellent", "fair" or "poor" depending upon the degree of recanalization and clinical improvement. A cannula was inserted into the radial artery in lung cancer patients before the procedure. Samples of blood to determine arterial blood gas levels were drawn before, during and after treatment. After bronchoscopic laser therapy, radiotherapy and/or chemotherapy were given to the patients of lung cancer.

RESULTS

The effective rate (excellent and fair) was 75% in lung cancer and 81.8% in benign airway obstruction. In the lung cancer group, significant decline of PaO2 was noted during and after Nd-YAG laser therapy. Decrease of PaO2 was not recovered even 5 hours after laser vaporization. After bronchoscopic Nd-YAG laser therapy, 21 of 32 lung cancer patients received radiotherapy (at least 3000 rads) and/or chemotherapy (at least 3 times). The median survival time was 5.5 months. The other 11 patients received laser therapy only, with median survival time was 2.9 months (p < 0.05).

CONCLUSIONS

Endobronchial Nd-YAG laser therapy of obstructing lesions has been proved to be effective and relatively safe in well-trained hands. Oxygen supplementation was suggested in patients with hypoxemia before laser therapy. After endobronchial Nd-YAG laser therapy, better survival and life quality result if radiotherapy and/or chemotherapy are added for the lung cancer group.

Multiple mitochondrial DNA deletions associated with age in skeletal muscle of rhesus monkeys

We have examined skeletal muscle for the presence of age-associated mitochondrial DNA (mtDNA) deletions from 16 rhesus monkeys (age range 6-27 years). All animals over 13 years of age contained potential mtDNA deletions, whereas the presence of deletions was greatly reduced or absent in younger animals. The specific deletion patterns varied from individual to individual. Numerous mtDNA deletions accumulate with age in skeletal muscle from a nonhuman primate, indicating that the rhesus monkey may provide an excellent animal model to study mtDNA deletions. Further, the existence of multiple mtDNA deletions supports the possibility that they may contribute to geriatric muscular deficits, which are nearly universal in occurrence yet poorly understood.

Microbial reduction of sulfur dioxide with pretreated sewage sludge and elemental hydrogen as electron donors

It has been demonstrated tht heat- and alkali-pretreated-sewage sludge may serve as an electron donor and carbon source for SO2 reduction by Desulfovibrio desulfuricans. A continuous D. desulfuricans culture was operated for 6 mo with complete reduction of SO2 to H2S. The culture required only minor amounts of mineral nutrients in addition to pretreated sewage sludge. It has also been shown that the sulfate-reducing bacterium Desulfotomaculum orientis can be grown on H2 as an energy source, CO2 as a carbon source, and SO2 as a terminal electron acceptor. Complete reduction of SO2 to H2S was observed.