Implantable cardioverter-defibrillators in heart transplant patients: a systematic review and meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background

Whilst implantable cardioverter-defibrillator (ICD) implantation is beneficial in a select group of patients, heart transplant patients were excluded from landmark clinical trials. Thus, controversy remains about the utility of ICD in high-risk heart transplant patients.

Purpose

To understand the utility, benefits and side-effects of ICD in heart transplant patients.

Methods

Five electronic databases were systematically searched from their inception to August 2021, in order to identify all studies which explored the role of ICD in heart transplant patients.  We used a random-effects model for data analysis based on event rates (ER) and 95% confidence interval (CI). Publication bias was assessed using funnel plots and Egger’s regression analysis.

Results

Eleven studies with 4648 heart transplant patients, 129 of whom received ICD, met the inclusion criteria for the meta-analysis. Studies included two multicentre retrospective cohort studies, four single centre retrospective cohort studies, two case series and three case reports. Of the 129 heart transplant patients with ICD, 74% were men, mean age at ICD implantation was 48.5 years, mean time from transplant to ICD was 99 months, and mean follow-up duration was 40 months.

The indication for ICD implantation was often multifactorial and included severe allograft vasculopathy (40%), the presence of left ventricular systolic dysfunction (37%), documented VT/VF (14%), unexplained syncope (14%), and history of cardiac arrest (13%).

Appropriate ICD therapy for patients occurred as an average event rate of 19% (95% CI 13%-27%) (I2 = 0% p = 0.66), Figure 1. Inappropriate therapy for patients occurred as an average event rate of 9% (95% CI 5%-16%) (I2 = 0% p = 0.96), Figure 2. There was no evidence of publication bias.

In total, nine ICD-related complications were reported including pocket haematoma (n = 1), pocket site infection (n = 2), infection of the ICD system (n = 1), lead displacement (n = 2) and lead fracture (n = 1). Mortality occurred in 28 patients, with heart failure being the leading primary cause of death (n = 10), followed by sepsis (n = 6), arrhythmia (n = 3) and electromechanical disassociation (n = 3).

Conclusion

Heart transplant patients with ICD more often received appropriate than inappropriate ICD shock therapy. The 19% appropriate ICD shock rate suggests a high burden of ventricular arrhythmias in high-risk heart transplant patients. Thus, ICD therapy may be beneficial in a select subset of heart transplant patients, keeping in mind even with appropriate shock therapy, subsequent terminal electromechanical disassociation and arrhythmias may imply ICD are not fully protective against arrhythmic aetiologies of mortality. Abstract Figure 1  Abstract Figure 2

Molecular and clinical characterization of citrin deficiency in a cohort of Chinese patients in Hong Kong

Background and objectives: This retrospective study analysed a case series of subjects with citrin deficiency, and aims to present the molecular and clinical characterization of this disease in the Hong Kong Chinese population for the first time. Patients and Methods: Data from medical records of eighteen patients with citrin deficiency (years 2006–2015) were retrieved. Demographic data, biochemical parameters, radiological results, genetic testing results, management, and clinical outcome were collected and analysed. Results: Eighteen patients with diagnosis of citrin deficiency were recruited. All 18 patients carried at least one common pathogenic variant c.852_855delTATG in SLC25A13. Prolonged jaundice (neonatal intrahepatic cholestasis caused by citrin deficiency, NICCD) was the most common presenting symptom, in conjunction with elevated plasma citrulline, threonine, alkaline phosphatase, and alpha-fetoprotein levels. The abnormal biochemical parameters including liver derangement returned to normal range in most of the cases by 6 months of age after the introduction of a lactose-free formula. There were a few cases with atypical presentations. Two subjects did not present with NICCD, and were subsequently diagnosed later in life after their siblings presented with symptoms of citrin deficiency at one month of age and subsequently received a molecular diagnosis. One patient with citrin deficiency also exhibited multiple liver hemangioendotheliomas, which subsided gradually after introduction of a lactose-free formula. Only one patient from this cohort was offered expanded metabolic screening at birth. She was not ascertained by conducted newborn screening and was diagnosed upon presentation with cholestatic jaundice by 1 month of age. Conclusion: This is the first report of the clinical and molecular characterization of a large cohort of patients with citrin deficiency in Hong Kong. The presentation of this cohort of patients expands the clinical phenotypic spectrum of NICCD. Benign liver tumors such as hemangioendotheliomas may be associated with citrin deficiency in addition to the well-known association with hepatocellular carcinoma. Citrin deficiency may manifest in later infancy period with an NICCD-like phenotype. Furthermore, this condition is not always ascertained by expanded newborn metabolic screening testing.

Variability in CT lung-nodule quantification: Effects of dose reduction and reconstruction methods on density and texture based features

Purpose:

To investigate the effects of dose level and reconstruction method on density and texture based features computed from CT lung nodules.

Methods:

This study had two major components. In the first component, a uniform water phantom was scanned at three dose levels and images were reconstructed using four conventional filtered backprojection (FBP) and four iterative reconstruction (IR) methods for a total of 24 different combinations of acquisition and reconstruction conditions. In the second component, raw projection (sinogram) data were obtained for 33 lung nodules from patients scanned as a part of their clinical practice, where low dose acquisitions were simulated by adding noise to sinograms acquired at clinical dose levels (a total of four dose levels) and reconstructed using one FBP kernel and two IR kernels for a total of 12 conditions. For the water phantom, spherical regions of interest (ROIs) were created at multiple locations within the water phantom on one reference image obtained at a reference condition. For the lung nodule cases, the ROI of each nodule was contoured semiautomatically (with manual editing) from images obtained at a reference condition. All ROIs were applied to their corresponding images reconstructed at different conditions. For 17 of the nodule cases, repeat contours were performed to assess repeatability. Histogram (eight features) and gray level co-occurrence matrix (GLCM) based texture features (34 features) were computed for all ROIs. For the lung nodule cases, the reference condition was selected to be 100% of clinical dose with FBP reconstruction using the B45f kernel; feature values calculated from other conditions were compared to this reference condition. A measure was introduced, which the authors refer to as Q, to assess the stability of features across different conditions, which is defined as the ratio of reproducibility (across conditions) to repeatability (across repeat contours) of each feature.

Results:

The water phantom results demonstrated substantial variability among feature values calculated across conditions, with the exception of histogram mean. Features calculated from lung nodules demonstrated similar results with histogram mean as the most robust feature (Q ≤ 1), having a mean and standard deviation Q of 0.37 and 0.22, respectively. Surprisingly, histogram standard deviation and variance features were also quite robust. Some GLCM features were also quite robust across conditions, namely, diff. variance, sum variance, sum average, variance, and mean. Except for histogram mean, all features have a Q of larger than one in at least one of the 3% dose level conditions.

Conclusions:

As expected, the histogram mean is the most robust feature in their study. The effects of acquisition and reconstruction conditions on GLCM features vary widely, though trending toward features involving summation of product between intensities and probabilities being more robust, barring a few exceptions. Overall, care should be taken into account for variation in density and texture features if a variety of dose and reconstruction conditions are used for the quantification of lung nodules in CT, otherwise changes in quantification results may be more reflective of changes due to acquisition and reconstruction conditions than in the nodule itself.

Studies of Pig Complement: Measurement of Pig CH50, ACH50, and Components

BACKGROUND

On the basis of a comparison of the hemolytic complement titer in pigs with that in humans, the complement system of pigs was investigated. The response of innate immunity, such as the natural antibodies, against humans was also examined.

METHODS

Hemolytic complement activity of pig serum was measured with the use of a microtitration technique. CH50 was determined according to the method of Mayer. ACH50 was assayed according to the methods of Platts-Milles and Ishizaka. Hemolytic activities of C1, C4, C2, C3, C5, C8, and C9 were estimated through the use of intermediate cells and reagents, as described previously. In addition, the pig natural anti-human antibody was studied with the use of human peripheral blood mononuclear cells (PBMCs). Human PBMCs were stained with 5% pig serum, followed by staining with fluorescein isothiocyanate-labeled goat anti-pig IgG and IgM. The resulting stained cells were quantified by use of a FACScalibur system. The alternative pathway of pig complement was also measured with the use of human erythrocytes and normal pooled pig serum with or without Mg(++)EGTA.

RESULTS

Both the CH50 and ACH50 titers were lower than those of humans. Concerning the components, except for C3, each component, that is, C1, C4, C2, C5, C8, and C9, was also lower than that of humans, based on measured values for human complement components. Pig serum clearly contains natural antibodies, IgG and IgM, to human PBMCs. The alternative pathway of pig complement reacted with human erythrocytes.

CONCLUSIONS

As a whole, pig innate immunity, the complement system and natural antibody, recognizes the surfaces of human cells.

Knockout of Cytidine Monophospho-N-Acetylneuraminic Acid (CMP-NeuAc) Hydroxylase From Porcine Endothelial Cells by a CRISPR System

BACKGROUND

We attempted to knock out the expression of Hanganutziu-Deicher (H-D) antigens through the use of a CRISPR (clustered regulatory interspaced short palindromic repeat)/Cas9 system for pig cytidine monophospho-N-acetylneuraminic acid hydroxylase (CMAH).

METHODS

Plasmids expressing hCas9 and sgRNA for pCMAH were prepared by ligating oligos into the BbsI site of pX330. The N-terminal and C-terminal EGFP coding regions overlapping 482 bp were PCR-amplified and placed under a ubiquitous CAG promoter. The approximately 400-bp genomic fragments containing the sgRNA target sequence of pCMAH were placed into the multi-cloning sites flanked by the EGFP fragments. The pCAG-EGxxFP-target was mixed with pX330 with/without the sgRNA sequences and then introduced into HEK293T cells.

RESULTS

Four oligos and primers, gSO1, gSO3, gSO4, and gSO8, were nominated from 8 candidates. Among them, gSO1 showed the best efficiency. Pig endothelial cells (PECs) from an α-Gal knockout pig were then used to examine the changes in the expression of the H-D antigen by the knockout of the CMAH genome by the pX330-gS01.

CONCLUSIONS

Changes in the expression of the H-D antigen in the PECs with the CRISPR (gS01) were clear in comparison with those in the parental cells, on the basis of FACS analysis data. The expression of the H-D antigen can be knocked out by use of the CRISPR system for pCMAH, thus confirming that this system is a very convenient system for producing knockout pigs.

Nucleosome positioning and composition modulate in silico chromatin flexibility

The dynamic organization of chromatin plays an essential role in the regulation of gene expression and in other fundamental cellular processes. The underlying physical basis of these activities lies in the sequential positioning, chemical composition, and intermolecular interactions of the nucleosomes-the familiar assemblies of ∼150 DNA base pairs and eight histone proteins-found on chromatin fibers. Here we introduce a mesoscale model of short nucleosomal arrays and a computational framework that make it possible to incorporate detailed structural features of DNA and histones in simulations of short chromatin constructs. We explore the effects of nucleosome positioning and the presence or absence of cationic N-terminal histone tails on the 'local' inter-nucleosomal interactions and the global deformations of the simulated chains. The correspondence between the predicted and observed effects of nucleosome composition and numbers on the long-range communication between the ends of designed nucleosome arrays lends credence to the model and to the molecular insights gleaned from the simulated structures. We also extract effective nucleosome-nucleosome potentials from the simulations and implement the potentials in a larger-scale computational treatment of regularly repeating chromatin fibers. Our results reveal a remarkable effect of nucleosome spacing on chromatin flexibility, with small changes in DNA linker length significantly altering the interactions of nucleosomes and the dimensions of the fiber as a whole. In addition, we find that these changes in nucleosome positioning influence the statistical properties of long chromatin constructs. That is, simulated chromatin fibers with the same number of nucleosomes exhibit polymeric behaviors ranging from Gaussian to worm-like, depending upon nucleosome spacing. These findings suggest that the physical and mechanical properties of chromatin can span a wide range of behaviors, depending on nucleosome positioning, and that care must be taken in the choice of models used to interpret the experimental properties of long chromatin fibers.

Similar worldwide patterns in the sex pheromone signal and response in the oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae)

The response of Grapholita molesta (Busck) males to three-component sex pheromone blends containing a 100% ratio of the major sex pheromone component, (Z)-8-dodecenyl acetate and a 10% ratio of (Z)-8-dodecenol, but with varying ratios of (E)-8-dodecenyl acetate (0.4, 5.4, 10.4, 30.4, and 100.1% E-blends) was tested with populations in eight stone and pome fruit orchards in Europe, Asia, and North and South America. Traps baited with the 5.4% E-blend caught significantly more males than traps with any other blend with all populations. Significantly more males were caught in traps baited with the 10.4% E-blend than in traps with the remaining blends, except with the 0.4% E-blend in Turkey. Significant differences in male moth catches occurred between the other blends with the 0.4>30.4% E-blend, and the 30.4>100.1% E-blend. Male moth catches with the 100.1% E-blend only differed from the hexane control in Chile. No apparent differences were noted to these blends in populations collected from pome or stone fruits. Flight tunnel assays to synthetic blends with a subset of populations were similar to the field results, but the breadth of the most attractive E-blends was wider. Flight tunnel assays also demonstrated a high level of male-female cross-attraction among field-collected populations. Female gland extracts from field-collected populations did not show any significant variation in their three-component blends. The only exceptions in these assays were that long-term laboratory populations were less responsive and attractive, and produced different blend ratios of the two minor components than recently collected field populations.

The tripeptide feG reduces endotoxin-provoked perturbation of intestinal motility and inflammation

Lipopolysaccharide (LPS)-induced intestinal endotoxaemia perturbs motility and causes activation and influx of inflammatory cells into the muscle tissue. Because rat submandibular gland peptide T (SGP-T; Thr-Asp-Ile-Phe-Glu-Gly-Gly), its carboxyl-terminal fragment tripeptide, FEG (Phe-Glu-Gly) and its D-isomeric analogue, feG, modulate intestinal anaphylactic reactions, we examined whether these peptides also modulate LPS-induced intestinal endotoxaemia in conscious rats. The disruption of the fasting pattern of intestinal MMCs (migrating motor complexes), induced by intravenous LPS (20 microg kg-1) injection, was prevented by all three peptides. The extravasation of leucocytes into the peritoneal cavity and increased expression of the activation marker CD18 on mesenteric tissue leucocytes (18 h after intraperitoneal injection of LPS) were reduced by orally administered feG, which also significantly decreased the number of intestinal tissue leucocytes expressing the integrin CD18. We conclude that feG attenuates both the immediate (intestinal motility) and late ( approximately 18 h) inflammatory reactions provoked by endotoxaemia.

Shunt malfunctions

Shunt failure remains a disheartening complication of shunt surgery. The number of adjustable factors in attempting to reduce the rate is small. The clinical presentation and timing of shunt malfunction are well documented. Although the shunt design trials have been negative to date, valves have important effects that have not as yet been translated to improved outcome.

Differences in tissue-specific and embryonic expression of mouse Ceacam1 and Ceacam2 genes

The intercellular adhesion molecule CEACAM1, also known as C-CAM1 (where CAM is cell-adhesion molecule), can function as a tumour suppressor in several carcinomas, including those of the prostate, breast, bladder and colon. This suggests that CEACAM1 may play an important role in the regulation of normal cell growth and differentiation. However, there is no direct evidence to support this putative function of CEACAM1. To elucidate its physiological function by targeted gene deletion, we isolated the Ceacam genes from a mouse 129 Sv/Ev library. Although there is only one Ceacam1 gene in humans and one in rats, two homologous genes (Ceacam1 and Ceacam2) have been identified in the mouse. Our sequence analysis revealed that the genes encoded nine exons and spanned approx. 16-17 kb (Ceacam1) and 25 kb (Ceacam2). The genes were highly similar (79.6%). The major differences in the protein-coding regions were located in exons 2, 5 and 6 (76.9%, 87.0% and 78.5% similarity respectively). In addition, introns 2, 5 and 7 were also significantly different, being 29.7%, 59.8% and 64.5% similar respectively. While most of these differences were due to nucleotide substitutions, two insertions of 418 and 5849 bp occurred in intron 2 of Ceacam2, and another two insertions of 1384 and 197 bp occurred in introns 5 and 7 respectively. To determine whether functional redundancy exists between Ceacam1 and Ceacam2, we examined their expression in 16 mouse tissues by using semi-quantitative reverse transcription-PCR. As in human and rat, in the mouse Ceacam1 mRNA was highly abundant in the liver, small intestine, prostate and spleen. In contrast, Ceacam2 mRNA was only detected in kidney, testis and, to a lesser extent, spleen. Reverse transcription-PCR using testis RNA indicated that Ceacam2 in the testis is an alternatively spliced form containing only exons 1, 2, 5, 6, 8 and 9. In the mouse embryo, Ceacam1 mRNA was detected at day 8.5, disappeared between days 9.5 and 12.5, and re-appeared at day 19. On the other hand, no Ceacam2 mRNA was detected throughout embryonic development. The different tissue expression patterns and regulation during embryonic development suggest that the CEACAM1 and CEACAM2 proteins, although highly similar, may have different functions both during mouse development and in adulthood.

Hmx: an evolutionary conserved homeobox gene family expressed in the developing nervous system in mice and Drosophila

Three homeobox genes, one from Drosophila melanogaster (Drosophila Hmx gene) and two from mouse (murine Hmx2 and Hmx3) were isolated and the full-length cDNAs and corresponding genomic structures were characterized. The striking homeodomain similarity encoded by these three genes to previously identified genes in sea urchin, chick and human, as well as the recently cloned murine Hmx1 gene, and the low homology to other homeobox genes indicate that the Hmx genes comprise a novel gene family. The widespread existence of Hmx genes in the animal kingdom suggests that this gene family is of ancient origin. Drosophila Hmx was mapped to the 90B5 region of Chromosome 3 and at early embryonic stages is primarily expressed in distinct areas of the neuroectoderm and subsets of neuroblasts in the developing fly brain. Later its expression continues in rostral areas of the brain in a segmented pattern, suggesting a putative role in the development of the Drosophila central nervous system. During evolution, mouse Hmx2 and Hmx3 may have retained a primary function in central nervous system development as suggested by their expression in the postmitotic cells of the neural tube, as well as in the hypothalamus, the mesencephalon, metencephalon and discrete regions in the myelencephalon during embryogenesis. Hmx1 has diverged from other Hmx members by its expression in the dorsal root, sympathetic and vagal nerve (X) ganglia. Aside from their expression in the developing nervous system, all three Hmx genes display expression in sensory organ development, and in the adult uterus. Hmx2 and Hmx3 show identical expression in the otic vesicle, whereas Hmx1 is strongly expressed in the developing eye. Transgenic mouse lines were generated to examine the DNA regulatory elements controlling Hmx2 and Hmx3. Transgenic constructs spanning more than 31 kb of genomic DNA gave reproducible expression patterns in the developing central and peripheral nervous systems, eye, ear and other tissues, yet failed to fully recapitulate the endogenous expression pattern of either Hmx2 or Hmx3, suggesting both the presence and absence of certain critical enhancers in the transgenes, or the requirement of proximal enhancers to work synergistically.

Three-dimensional structure of the human herpesvirus 8 capsid

Human herpesvirus 8 (HHV-8), or Kaposi's sarcoma-associated herpesvirus, is a gammaherpesvirus implicated in all forms of Kaposi's sarcoma and certain lymphomas. HHV-8 has been extensively characterized, both biochemically and immunologically, since its first description in 1994. However, its three-dimensional (3D) structure remained heretofore undetermined largely due to difficulties in viral purification. We have used log-phase cultures of body cavity-based lymphoma 1 cells induced with 12-O-tetradecanoylphorbol-13-acetate to obtain HHV-8 capsids for electron cryomicroscopy and computer reconstruction. The 3D structure of the HHV-8 capsids revealed a capsid shell composed of 12 pentons, 150 hexons, and 320 triplexes arranged on a T=16 icosahedral lattice. This structure is similar to those of herpes simplex virus type 1 (HSV-1) and human cytomegalovirus (HCMV), which are prototypical members of alpha- and betaherpesviruses, respectively. The inner radius of the HHV-8 capsid is identical to that of the HSV-1 capsid but is smaller than that of the HCMV capsid, which is consistent with the relative sizes of the genomes they enclose. While the HHV-8 capsid exhibits many structural similarities to the HSV-1 capsid, our reconstruction shows two major differences: its hexons lack the "horn-shaped" VP26 densities bound to the HSV-1 hexon subunits, and the HHV-8 triplexes appear smaller and less elongated than those of HSV-1. These differences are in excellent agreement with our sequence comparisons of HHV-8 and HSV-1 capsid proteins. This gammaherpesvirus capsid structure complements previous structural studies on alpha- and betaherpesviruses in providing an account of structural similarities and differences among capsids representing all human herpesvirus subfamilies.

Insecticide resistance management of leafrollers (LepidopteraTortricidae) in New Zealand

Resistance to the organophosphate insecticide azinphosmethyl has been previously identified in two species of leafroller (Lepidoptera Tortricidae) in New Zealand This study confirmed resistance in a third speciesCtenopseustis obliquana Populations of Epiphyas postvittana Planotortrix octo and C obliquana resistant to azinphosmethyl were not crossresistant to lufenuron A separate population of C obliquana was resistant to taufluvalinate Crossresistance between azinphosmethyl and tebufenozide occurred in P octo and C obliquana but not in E postvittana This difference in crossresistance between the three species suggests that at least two different detoxification mechanisms may be operating Therefore we cannot generalise about whether resistant populations of each species will be fully susceptible to new insecticides Lufenuron is recommended as a key insecticide within a resistance management programme for leafrollers while tebufenozide should be used with caution

Time of leafroller infestation and effect on yield in grapes

Leafroller (Lepidoptera Tortricidae) larvae damage grape bunches directly by feeding on the flowers berries and stalks Damaged berries can become infected by fungi such as Botrytis cinerea that cause diseases leading to further indirect yield losses In a field trial Chardonnay bunches were infested with lightbrown apple moth Epiphyas postvittana larvae at monthly intervals from December to March The greatest losses (12 of the fresh weight at harvest) occurred in bunches infested in December and March In December the main cause of loss of berries was direct feeding damage whereas by March indirect losses to disease outweighed those directly due to larvae Leafroller infestations up to January did not increase disease in bunches above the background level of infection In Hawkes Bay leafrollers have the greatest effect on yields from February onwards when infestation of vines increases greatly and berries become more susceptible to diseases

Efficacy of ondansetron for prevention of postoperative nausea and vomiting after outpatient ear surgery under local anesthesia

OBJECTIVE

To assess the efficacy and safety of intravenous ondansetron (4 mg) for the prevention of nausea and vomiting after middle ear surgery under local anesthesia.

SETTING

The study was conducted by Division of Otorhinolaryngology in Prince of Wales Hospital, which is a tertiary referral center and teaching hospital for The Chinese University of Hong Kong.

STUDY DESIGN

A double-blind randomized controlled trial.

PATIENTS

Fifty-eight Chinese patients undergoing tympanoplasty under local anesthesia from July 1995 to June 1997 were recruited. The mean age of patients was 42.8 years (range 18-71 years).

INTERVENTION

Patients were randomly allocated to receive a single dose of intravenous ondansetron (4 mg) (n = 29) or placebo (n = 29) immediately before surgery.

MAIN OUTCOME MEASURES

Patients were assessed for severity and frequency of postoperative nausea and vomiting at the 1st, 2nd, 4th, 8th, and 24th hours after middle ear surgery.

RESULTS

Female patients showed a higher prevalence of postoperative nausea and vomiting. Twenty-eight percent of the patients experienced postoperative nausea, of whom 14% also experienced vomiting. Although the ondansetron group demonstrated a lower prevalence of postoperative nausea and vomiting (PONV) (24% nausea and 10% vomiting) than the placebo group (31% nausea and 17% vomiting), significant reduction in postoperative vomiting only occurred in the first postoperative hour (p = 0.038). No complications or adverse side effects were found to be associated with the use of ondansetron.

CONCLUSIONS

Single-dose ondansetron (4 mg) given intravenously preoperatively significantly reduces postoperative vomiting in patients after tympanoplasty under local anesthesia and causes no adverse effects.

Expression and androgen regulation of C-CAM cell adhesion molecule isoforms in rat dorsal and ventral prostate

C-CAM is an epithelial cell adhesion molecule with two major splice variants that differ in the length of the cytoplasmic domain. C-CAM1 (long (L)-form) strongly suppresses the tumorigenicity of human prostate carcinoma cells. In contrast, C-CAM2 (short (S)-form) does not exhibit tumor-suppressive activity. In the present study we have investigated the functional significance of L-form and S-form C-CAM in rat prostate by examining their expression and distribution in different prostate lobes and their response to androgen deprivation. RNase protection assays with a probe for both C-CAM isoforms detected high levels of C-CAM messages in the rat dorso-lateral prostate (DLP). L- and S-form proteins, localized by indirect immunofluorescence using isoform-specific antipeptide antibodies, were co-expressed on the apical surface of prostate epithelial cells in normal DLP. Androgen depletion did not significantly change the steady state levels of C-CAM message and protein expression in the DLP, although there was a change in the pattern of protein expression in these lobes. In contrast, C-CAM isoform messages and proteins were undetectable in normal ventral prostate (VP) but increased markedly in this lobe in response to castration, producing isoform ratios similar to those in DLP. These results demonstrate that coordinate expression of C-CAM isoforms is maintained in the VP following androgen depletion and suggest that androgen suppresses C-CAM expression in VP but not in DLP. These results suggest that balanced expression of L- and S-form C-CAM is important for normal prostate growth and differentiation.

Attenuation of intestinal and cardiovascular anaphylaxis by the salivary gland tripeptide FEG and its D-isomeric analog feG

The effects of the submandibular gland peptide-T (SGP-T; Thr-Asp-Ile-Phe-Gly-Gly; TDIFEGG), its carboxy-terminal fragment (the tripeptide FEG; Phe-Glu-Gly), and the D-isomeric analog (feG) on intestinal and cardiovascular anaphylactic reactions were studied. The tripeptides, FEG and feG, when administered intravenously or orally to egg albumin-sensitized Hooded Lister or Sprague-Dawley rats 30 min prior to challenge with the antigen, totally prevented the disruption of intestinal motility and the development of anaphylaxis provoked diarrhea and inhibited anaphylactic hypotension by 66%. Submandibular gland peptides participate in the regulation of systemic inflammatory reactions, and the D-amino acid tripeptide, feG, is a potent, orally active anti-anaphylactic agent.

bcl-2 expression confers androgen independence in androgen sensitive prostatic carcinoma

Expression of the bcl-2 proto-oncogene is associated with the progression of prostate cancer to androgen-independence. Dunning R3327G (DG) cells were engineered to express high levels of bcl-2 protein. The parental DG (DG-P) cell line and bcl-2 transfectant (DG-B) clones were grown as subcutaneous tumor explants in male athymic nude mice. The rate of tumor growth after castration was significantly lower in DG-P tumors but was unaffected in DG-B tumors. The proliferative indices (PI) in DG-P and DG-B tumors were similar, however, apoptotic indices (ApI) were significantly lower in DG-B tumors before castration. Following castration the PI and ApI decreased significantly in DG-P but not DG-B tumors. Bax upregulation was not observed in the DG-P or DG-B tumors, but did occur in the ventral prostate, after castration. These findings support a role for bcl-2 expression in conferring androgen-independent growth during prostate cancer progression.

Importance of the Bcl-2 family in cell death regulation

Bcl-2 was first identified as a novel transcript associated with the t(14;18) chromosomal breakpoint which occurs in most follicular lymphomas. The deregulated expression of bcl-2 was found to contribute to multistep neoplasia through the suppression of cell death, or apoptosis, in transgenic mouse models. Bcl-2 was subsequently shown to be normally expressed in a variety of tissues and to significantly inhibit the induction of apoptosis in many experimental systems. Bcl-2 is now known to be structurally similar to other proteins, in particular within the domains referred to as BH1 and BH2. This multigene family of cell death regulators includes members which enhance rates of apoptosis, including bcl-xs and bax, and those which inhibit apoptosis, including MCL-1 and bcl-xL. Members of the bcl-2 family physically interact with other proteins, including other family members and these interactions appear to modulate their function. The mechanism(s) by which bcl-2 family members regulate cell death remain in large part unknown, although recent evidence suggests that bcl-2 may interfere with cellular signalling events involved in apoptosis induction.

Overexpression of Bcl-2 and mutations in p53 and K-ras in resected human non-small cell lung cancers

We investigated expression of Bcl-2, mutations in p53, and K-ras oncogene in 51 resected human non-small cell lung cancers. The studies were designed to test for the possibility of cooperativity between these oncogenes and p53 in the pathogenesis of lung cancer. An inverse relationship was found between expression of Bcl-2 and mutant p53 by immunohistochemistry (P < 0.01; Fisher exact test), suggesting that either Bcl-2 overexpression or mutations in p53 may fulfill a critical function in the pathogenesis of human non-small cell lung cancers. Tumors that harbored K-ras codon 12 mutations seldom had p53 mutations or overexpressed Bcl-2. Statistical analysis of these data showed that mutations in p53 and K-ras or overexpression of Bcl-2 and mutations in K-ras occurred at a frequency that could be explained only by chance [P > 0.1 in each case (Fisher exact tests)]. This suggests that cooperativity between mutant K-ras and mutant p53 or mutant K-ras and overexpressed Bcl-2 is not a common mechanism in the pathogenesis of human non-small cell lung cancers.

Evaluation of accuracy and reproducibility of E test for susceptibility testing of Streptococcus pneumoniae to penicillin, cefotaxime, and ceftriaxone

We evaluated the reproducibility with which technologists perform and interpret the E test (AB Biodisk, North America, Inc., Piscataway, N.J.) for determining the susceptibility of Streptococcus pneumoniae to penicillin, cefotaxime, and ceftriaxone. Four technologists prepared E test assays to test 124 isolates of S. pneumoniae. Each technologist then interpreted the results of the E test blinded to the interpretation of the other technologists. In addition, E test results were compared with the reference method of broth microdilution. Intraobserver and interobserver agreement were assessed by use of the kappa statistic. Interpretation of the E test and broth microdilution results showed substantial to excellent agreement, with kappa values ranging from 0.878 to 0.987. Compared with broth microdilution, no very major errors and only four major errors were made with the E test. Most minor errors with penicillin and ceftriaxone occurred for isolates with intermediate or high-level resistance, whereas for cefotaxime the minor errors were more evenly distributed between susceptible and intermediate resistance and between intermediate and high-level resistance. These results indicate that there is good agreement between technologists for the interpretation of the E test when testing the susceptibility of S. pneumoniae to penicillin, cefotaxime, and ceftriaxone and that the results of the E test agree with those of broth microdilution.

Mating in the heterothallic haploid yeast Clavispora opuntiae, with special reference to mating type imbalances in local populations

Mating was studied in the haploid, heterothallic yeast Clavispora opuntiae to assess the importance of nutritional, genetic, and other factors that may favour mating and recombination. Local populations of this yeast generally exhibit dramatic inequalities in mating type distributions, suggesting that mating is rare in nature even though most isolates mate freely in the laboratory. The absence of assimilable nitrogen is prerequisite to mating competence, presumably by causing G1 arrest. Maximum mating competence is found in cells entering stationary phase in nitrogen-limited media. Unlike the vast majority of mating yeasts, C. opuntiae does not appear to produce diffusible mating factors (sex pheromones), and mating-competent cells do not undergo sexual agglutination. Pairwise cell contact appears to be the only signal that triggers the sexual process in this case. In order to determine if mating type imbalances in nature are caused by reduced fertility of 'consanguine' crosses, meiotic recombination was measured in pairs of strains that varied in their genetic distances as indicated by restriction mapping. That hypothesis was rejected, as recombination efficiency decreased with increasing genetic distance. We conclude that the rarity of mating in local populations is exacerbated by the stringent physical (pairwise cell contact) and nutritional (nitrogen depletion) conditions that will allow mating to proceed. Parallels are drawn with mating patterns observed in Clavispora lusitaniae.

Utilization review of the use of BACTEC PLUS high-volume blood culture bottles

The BACTEC PLUS 26 (NR26) (Becton Dickinson, Towson, Md.) high-volume blood culture bottle replaced the less expensive smaller-volume NR6A bottle in our hospital. An audit carried out several months after their introduction revealed that only 17.5% of the NR26 bottles received the required blood volume. Several audits and educational programs were required in order to achieve a compliance rate of > 60%.

Local cerebral glucose utilization rate following intermittent exposures to 2 atmosphere absolute oxygen

Previous studies have shown significant increases in regional cerebral metabolic rate for glucose (rCMRgl) in 14 of 28 investigated brain structures in rats exposed to 1-h oxygen at 2 atmosphere absolute (ATA O2). Continuous 4-h exposure to 2 ATA O2 resulted in significant increases only in superior olivary nucleus and inferior colliculus. In the present study, the rCMRgl was autoradiographically measured by the [14C]2-deoxyglucose technique during the last 30 min of 4 intermittent 1-h exposures to either 2 ATA O2 or air at atmospheric pressure, with 3 h of breathing air outside the pressure chamber between each oxygen or air exposure. Statistically significant reductions in rCMRgl of the oxygen-exposed rats were observed in superior olivary nucleus and inferior colliculus, while no changes were observed in 26 other investigated structures. The previously observed increases in rCMRgl in a single 1- or 4-h exposure at 2 ATA O2 were reduced or reversed during the intermittent hyperbaric oxygen exposure. The relation of the observed changes in rCMRgl during single and intermittent hyperbaric oxygen exposures to the extension of tolerance to hyperbaric oxygenation is discussed.

Immunologic study on nasopharyngeal carcinoma patients: correlation of in vivo and in vitro reactivity to phytohemagglutinin

The skin response to 5 micrograms of purified phytohemagglutinin (PHA) was studied in 125 subjects, including 32 normal controls, 31 patients with head and neck cancer other than nasopharyngeal carcinoma (NPC), and 62 NPC patients. In vitro lymphocyte transformation to PHA (M form) was tested simultaneously to examine its correlation to the PHA skin test. A positive reaction of skin test was observed 24 hours after injection in 29 (90.6%) of 32 normal controls, 16 (51.6%) of 31 patients with head and neck cancer other than NPC, and 51 (82.3%) of 62 NPC patients respectively. Histological examination of the area of erythema revealed the same as those found in the delayed hypersensitivity with perivascular mononuclear cell infiltration. The PHA skin test was repeated 3 times over a period of 9 weeks in 10 normal controls, and no significant change in their skin reactivity was detected. In vitro reactivity to PHA-M was hyporesponsive in NPC patients than in normal controls in three measurements i.e. net counts of incorporated tritiated thymidine, stimulation index, or differences of square roots of counts between the well with PHA and without PHA. Net counts proved to be the most sensitive criterion to differentiate the lymphocyte response to PHA between NPC and normal controls. It is suggested that the general hyporesponsiveness to PHA stimulation in NPC is due to intrinsic T-cell dysfunction. The suboptimal dose of PHA for lymphocyte transformation in NPC was 2.5 microliters per 1.5 X 10(5) cells. Quantitatively, the correlation between in vivo and in vitro reactivity to PHA was not found in normal controls, yet it proved to have a good correlation in some NPC patients--in stage III r = 0.63, p greater than 0.05; in stage IV r = 0.71, p less than 0.01; in stage V r = 0.95, p less than 0.001. Qualitatively (delta cpm greater than or equal to 20,000; erythema greater than or equal to 20 mm), a correlation was found between in vivo and in vitro reactivity to PHA in 27 (84.4%) of 32 normal controls (p less than 0.001), and 39 (62.9%) of 62 NPC patients (p less than 0.01). It is concluded that if in vitro testing of PHA stimulation can not be done, the PHA skin test can be used as an alternative to screen the T-cell functions of NPC patients.

Stability of oral liquid penicillins in unit dose containers at various temperatures

The effect of freezing on the stability of reconstituted, unit dose packaged oral amoxicillin trihydrate and ampicillin suspensions and penicillin V potassium solutions was studied. Powders for suspension or solution of the three penicillins were reconstituted according to manufacturers' directions to yield a concentration of 250 mg/5 ml. Samples of 5 ml then were stored in amber, screw-cap, glass vials at 25 C, 5 C, 0 C, -10 C or -20 C for 5, 10, 20, 30 or 60 days. The concentration of active constituents remaining after storage was determined spectrophotometrically. All three penicillins retained at least 90% of their original activity for at least 60 days when stored at -20 C. Ampicillin and pencillin V potassium retained at least 90% of their activity after 60 days of storage at -10 C but amoxicillin concentration decreased to 88% and 87% of initial concentration after 60 days storage at -10 C and 0 C, respectively. Degradation appeared to be by a zero-order process for amoxicillin and ampicillin and by a first-order process for penicillin V potassium. It appears that oral solutions of amoxicillin, ampicillin and penicillin V potassium can be effectively stored for at least 50 days in a freezer at -10 C with little loss of activity.

Granulovacuolar degeneration in the ageing brain and in dementia

Quantitative morphometry with a sampling stage light microscope was performed to determine the severity of granulovacuolar degeneration of hippocampal neurones in serially sectioned temporal lobe from mentally normal subjects of different ages and from demented patients. The degree of granulovacuolar change in control brains increased slightly with increasing age; the "granulovacuolar index" of cases with Alzheimer's disease exceeded by many times that of age-matched controls. This significant difference was demonstrable whether the granulovacuolar severity was expressed as number of affected cells per volume of cortex analysed, or as the percentage involvement of total neurones counted in the hippocampus. The posterior half of each dement's hippocampus was found to be more susceptible to this augmented granulovacuolar degeneration than the anterior half, a selectivity already observed for neurofibrillary tangel formation in the same material.