Microbe defines the efficacy of chemotherapeutic drug: a complete paradigm

The human body harbors a diverse microbiome that regulates host physiology and disease development. Several studies have also been reported where the human microbiome interferes with the efficacy of chemotherapeutics. Reports have also suggested the use of microbes in specific targeting and drug delivery. This review mainly focuses on the alteration in the efficacy of the drug by human microbiota. We have also discussed how the diversity in microbes can determine the therapeutic outcomes of a particular drug. The pathways involved in the alteration are also focused, with some highlights on microbes being used in cancer therapy.

Retrosternal goiter in thoracic surgical practice

OBJECTIVE

To evaluate and optimize surgical approaches to the management of retrosternal goiter.

MATERIAL AND METHODS

A cohort retrospective single-center study included 56 patients aged 68.3±9.8 years with retrosternal goiter who underwent surgery between 2004 and 2019. Right-sided goiter was diagnosed in 16 cases, left-sided goiter in 21 patients, bilateral goiter in 19 patients. Palpable neck mass was found in 17 (30.4%), stridor in 16 (28.6%), thyrotoxicosis in 4 (7.1%) and recurrent laryngeal nerve palsy in 2 (3.6%) cases. X-ray signs of tracheal compression were detected in 43 (76.8%) patients, deviation in 26 (46.4%) patients. Resection through cervical collar incision was performed in 40 (71.4%) patients. Additional sternotomy was required in 11 (19.6%) patients, 1 (1.8%) patient required collar incision and right anterior mediastinotomy. Right-sided posterolateral thoracotomy without collar incision was performed in 1 (1.8%) patient with a suspected mediastinal teratoma. Three patients underwent median sternotomy only because of preoperative diagnosis of teratoma in one and thymoma in two patients.

RESULTS

There was no perioperative mortality. Transient vocal changes occurred in 3 (5.4%) patients, recurrent laryngeal nerve palsy in 3 (5.4%), atrial fibrillation in 2 (3.6%), wound complications in 2 (3.6%), left phrenic nerve palsy in 1 (1.8%), transient hypocalcaemia in 1 (1.8%) and persistent hypothyroidism in 1 (1.8%) patient. Hospital-stay ranged from 2 to 12 (5.5±2.0) days. Multinodular goiter was found in 53 (94.6%) patients, diffuse goiter in 1 (1.8%), ectopic thyroid in 1 (1.8%) and oncocytic tumor in 1 (1.8%) patient. One (1.8%) patient underwent simultaneous resection of RSG via a collar incision and right-sided VATS upper lobectomy for primary lung cancer. One (1.8%) patient also underwent simultaneous resection of RSG via collar incision and right-sided VATS subcarinal lymph node biopsy for coexistent lymphoma. Mean vertical length of goiter in the collar incision group was 7.6 cm compared to 10.6 cm in the sternotomy group. Mean weight of specimens was 162.3 g in patients with collar incisions and 312.5 g in the sternotomy group. Sternotomy was required in 14 (25%) patients.

CONCLUSION

Resection of retrosternal goiter is more commonly performed via cervical collar incision with mandatory availability of sternotomy. Radiological measurement of craniocaudal length may predict the need for sternotomy. Surgical outcomes are not affected by surgical approach. Simultaneous thoracic interventions for a coexistent pathology in patients with RSG may be considered. Further research of minimally invasive interventions for RSG resection is required.

Flexible Bronchoscopy Under Bronchoscopist-Administered Moderate Sedation Versus General Anesthesia: A Comparative Study in Children

Background: Flexible bronchoscopy (FB) can be performed under bronchoscopist administered moderate sedation (BAMS) with a midazolam/fentanyl combination or general anesthesia (GA). However, the outcome of BAMS has not been well established in children. Currently, most of the centers prefer FB under GA. Both techniques have their advantages and disadvantages with implications for safety, complications, and diagnostic yield. The primary objective of our study was to evaluate the safety, time efficiency, and cost-effectiveness of FB under BAMS as compared with FB under GA in a similar setting. Methods: We performed a retrospective chart review to compare BAMS versus GA for FB in children. We recruited BAMS children (n = 295) from University of Florida (UF) Health Shands Children's Hospital, and GA children (n = 100) from Penn State Children's Hospital (PSHCH). Both the groups had similar indications, complexities, and procedural environments. Comparisons of various time-intervals including preprocedure time, sedation-induction time, scope time, and post-procedure time among different BAMS versus GA age-groups were the primary outcomes. The secondary outcomes were the determination of the rates of complications, the dosages of sedative/anesthetic, cost-effectiveness, and sedation patterns under BAMS. Results: FB under BAMS required significantly higher preprocedure times and sedation-induction times (P < 0.001** and P < 0.001** respectively) but shorter scope and post-procedure times compared with the GA group times (P < 0.001** and P < 0.001** respectively). Younger children had a deeper level of sedation for an extended period under BAMS. The costs for the sedation services and the complication rates were lower in the BAMS group compared with the GA group. Conclusion: Our study demonstrated the feasibility of BAMS in children. FB under BAMS had an advantage of lower cost and fewer procedural complications compared with FB under GA. Despite that, the safety of BAMS could not be conclusively established from this retrospective study. Moreover, BAMS can potentially compromise the diagnostic yield because the bronchoscopist is also responsible for monitoring sedation and managing the airway.

Validation of International Classification of Disease Ninth Revision codes for atopic dermatitis

BACKGROUND

Evaluation of large-scale data sets is needed to better understand the epidemiology, cost, and burden of atopic dermatitis (AD). We sought to validate the use of ICD-9-CM codes for identifying AD.

METHODS

Patients from a large metropolitan quaternary care medical center with a diagnostic code of either 691.8 (AD) or 692.9 (eczema and contact dermatitis) were queried. Medical records were reviewed for demographics, Hanifin & Rajka (H&R) and United Kingdom Working Party (UKWP) criteria. Sensitivity, specificity, and positive predictive values (PPV) of the codes were calculated.

RESULTS

Of 43 278 patients identified with associated ICD-9 codes of 691.8 or 692.9, 519 and 253 with 691.8 and 692.9 were randomly selected for chart review. There was extensive overlap: 34.3% had ≥1 occurrences of 691.8 and 692.9 and 25.6% had multiple occurrences of both codes. Among patients with ≥1 occurrence of 691.8, 29.9% and 30.8% met the H&R and UKWP criteria, respectively. Similarly, among patients with ≥1 occurrence of 692.9, 33.7% and 32.2% met the H&R and UKWP criteria. Increased PPV was associated with concomitant diagnoses of asthma, hay fever, and food allergy and increased disease severity.

CONCLUSIONS

In the outpatient setting, the ICD-9-CM codes 691.8 and 692.9 alone have poor PPV. Incorporation of diagnoses of asthma, hay fever, and food allergy improves PPV and specificity. In the inpatient setting, a primary discharge diagnosis of 691.8 had excellent PPV. Although ICD-10 has been adopted in Europe and more recently in the USA, the same systematic errors would likely occur unless providers standardize their coding.

Impact of calcineurin-inhibitor conversion to mTOR inhibitor on renal allograft function in a prednisone-free regimen

Traditionally, chronic calcineurin inhibitor (CNI) nephrotoxicity has been considered to be one of the main nonimmune mechanisms causing chronic renal allograft dysfunction. CNI minimization and withdrawal strategies have yielded inconsistent results. Few studies address the feasibility of CNI elimination in a prednisone-free regimen. We report a prospective, randomized trial in 200 patients evaluating the impact on renal function and incidence of acute rejection after conversion from tacrolimus (Tac) to sirolimus (SRL). Patients with recent (<3 months) acute rejection episodes or with >0.5 g/day of proteinuria were excluded. All were induced with alemtuzumab, underwent rapid steroid elimination and were maintained on mycophenolate mofetil and Tac. At 12 months posttransplant, patients were randomized 2:1 to SRL (n = 123) or maintained on Tac (n = 64). Mean follow-up was 41.1 ± 15.8 months in the SRL group and 40.7 ± 14.4 months in the Tac group. Biopsy-proven acute rejection at 24 months postrandomization was similar between the groups. Patient survival, graft survival and estimated GFR were also not statistically different. Our study demonstrates that in a prednisone-free immunosuppressive regimen, conversion from Tac to SRL at 12 months posttransplantation is not associated with increased rates of acute rejection and graft loss. However, despite CNI elimination, renal allograft function is equally maintained in both groups.

Association between plasma cyclic guanosine monophosphate levels and hemodynamic instability during liver transplantation

The activation of cyclic guanosine monophosphate (cGMP) production in patients with end-stage liver disease (ESLD) has been associated with hemodynamic instability during orthotopic liver transplantation (OLT). The aim of this prospective, observational study was to investigate the involvement of cGMP in the mediation of profound hypotension during liver graft reperfusion. An additional objective was to determine whether preoperative cGMP levels are associated with intraoperative hemodynamic instability. Forty-four consecutive patients undergoing OLT were included in the study. Blood samples for cGMP analysis were obtained from (1) the radial artery before the surgical incision; (2) the radial artery, portal vein, and flush blood during the anhepatic phase; and (3) the radial artery 20 minutes after liver graft reperfusion. On the basis of a statistical analysis, the patients were divided into 2 groups: group 1 (preoperative cGMP level ≥ 0.05 μmol/L) and group 2 (preoperative cGMP level < 0.05 μmol/L). We demonstrated a significant correlation between the preoperative levels of cGMP and the amount of catecholamine required to maintain hemodynamic stability during reperfusion (r = 0.52, P < 0.001), the length of the hospital stay (r = 0.38, P = 0.01), and the length of the intensive care unit (ICU) stay (r = 0.44, P = 0.004). We also demonstrated a significantly higher intraoperative catecholamine requirement (P < 0.001) and a prolonged postoperative ICU stay (P = 0.02) in group 1 patients versus group 2 patients. In conclusion, this study demonstrates increased baseline cGMP production in patients with ESLD, which is significantly associated with severe hypotension during OLT. We suggest that preoperative levels of cGMP correlate with hemodynamic instability during liver graft reperfusion.

Role of tacrolimus combination therapy with mycophenolate mofetil in the prevention of organ rejection in kidney transplant patients

Introduction:

Several new medications are now available for immunosuppression in the kidney transplant field. Tacrolimus and mycophenolate mofetil were first introduced for immunosuppression in renal transplantation in the mid 1990s. Since then, the combination of tacrolimus and mycophenolate mofetil has been evaluated in numerous clinical trials. The outcomes of these trials have varied due to differences in induction and/or maintenance therapy, drug dosing and monitoring protocols, and study design. The aim of this review is to analyze the literature critically and to provide an overview of tacrolimus and mycophenolate mofetil combination therapy in renal transplantation.

Standard method for developing stroke registers in low-income and middle-income countries: experiences from a feasibility study of a stepwise approach to stroke surveillance (STEPS Stroke)

BACKGROUND

Stroke is a leading global cause of death, with an estimated 5.8 million fatal events in 2005, two-thirds of which happened in low-income and middle-income countries. In these regions, epidemiological methods to establish hospital-based stroke registers for clinical audit or studies to estimate incidence are scarce. Our aim was to ascertain whether stroke registers could be set up in geographically diverse populations in low-income and middle-income countries, using standardised data-collection manuals and methods, before recommending their wider use.

METHODS

WHO's stepwise approach to stroke surveillance (STEPS Stroke) offers an entry point for countries to register stroke patients in health-information systems. The methods proposed in this strategy were tested in a feasibility study, which focused on hospitalised stroke patients in nine different surveillance sites located in five low-income and middle-income countries. Data collection was for a median of 12 months. Observed differences between men and women were adjusted for age and surveillance site with logistic-regression analyses.

FINDINGS

A total of 5557 stroke patients were registered; 91 people whose age was missing or younger than 15 years were excluded from the analyses. Mean age was 64.2 years (SD 14.6), and 2484 (45%) participants were women. Ischaemic stroke accounted for about two-thirds of events. Half of all patients were hospitalised the same day. Stroke subtype was verified in 4913 (90%) participants by diagnostic techniques. Women had lower odds of verification of stroke subtype compared with men after adjustment for age and surveillance site (odds ratio 0.69 [95% CI 0.56-0.86]; p=0.0006).

INTERPRETATION

STEPS Stroke can be used in diverse populations to provide data in a standardised manner in countries with little or no previous records of stroke. Future studies should concentrate on expansion beyond hospital case series by adding information for stroke patients treated outside the hospital, linked to census data for the source population from which the cases come.

Spin-based logic in semiconductors for reconfigurable large-scale circuits

Research in semiconductor spintronics aims to extend the scope of conventional electronics by using the spin degree of freedom of an electron in addition to its charge. Significant scientific advances in this area have been reported, such as the development of diluted ferromagnetic semiconductors, spin injection into semiconductors from ferromagnetic metals and discoveries of new physical phenomena involving electron spin. Yet no viable means of developing spintronics in semiconductors has been presented. Here we report a theoretical design that is a conceptual step forward-spin accumulation is used as the basis of a semiconductor computer circuit. Although the giant magnetoresistance effect in metals has already been commercially exploited, it does not extend to semiconductor/ferromagnet systems, because the effect is too weak for logic operations. We overcome this obstacle by using spin accumulation rather than spin flow. The basic element in our design is a logic gate that consists of a semiconductor structure with multiple magnetic contacts; this serves to perform fast and reprogrammable logic operations in a noisy, room-temperature environment. We then introduce a method to interconnect a large number of these gates to form a 'spin computer'. As the shrinking of conventional complementary metal-oxide-semiconductor (CMOS) transistors reaches its intrinsic limit, greater computational capability will mean an increase in both circuit area and power dissipation. Our spin-based approach may provide wide margins for further scaling and also greater computational capability per gate.

Assessing bupivacaine 10mg/fentanyl 20μg as an intrathecal test dose

After ethics committee approval and verbal consent, women undergoing elective caesarean section given spinal anaesthesia with hyperbaric 0.5% bupivacaine 10 mg (2 mL) plus fentanyl 20 microg (spinal group, n = 20) and women requesting epidural analgesia in labour given the same drugs and doses epidurally, either in the same concentration (epidural small volume group, n = 10) or as 10 mL of 0.1% bupivacaine plus fentanyl 20 microg (epidural large volume group, n = 12) were recruited. The temperature of the great toes, sensory block on the outer ankle (S1 dermatome), motor block at the ankle and haemodynamic changes were recorded every 2 min for 10 min. There was a significant rise in foot temperature only in the spinal group. At four minutes a combination of warm toes and motor or sensory block, usually both, were seen only in the spinal groups. Haemodynamic changes were non-specific. We conclude that bupivacaine 10 mg with fentanyl 20 microg is a reliable agent to detect intrathecal placement by 4 min by which time a combination of motor and sensory block at the ankle and toe warming should be present.

Source of the ice-binding specificity of antifreeze protein type I

Antifreeze proteins (AFPs) are a group of structurally very diverse proteins with the unique capability of binding to the surface of seed ice crystals and inhibiting ice crystal growth. The AFPs bind with high affinity to specific planes of the ice crystal. Previously, this affinity of AFPs has been ascribed to the formation of multiple hydrogen bonds across the protein-ice interface, but more recently van der Waals interactions have been suggested to be the dominant energetic factors for the adsorption. To determine whether van der Waals interactions are also responsible for the binding specificities of AFPs, the protein-ice interaction of the helical AFP Type I from winter flounder (HPLC6) was studied using a Monte Carlo rigid body docking approach. HPLC6 binds in the [1102] direction of the [2021] plane, with the Thr-Ala-Asn surface comprising the protein's binding face. The binding of HPLC6 to this ice plane is highly preferred, but the protein is also found to bind favorably to the [1010] prism plane using a different protein surface comprised of Thr and Ala residues. The results show that van der Waals interactions, despite accounting for most of the intermolecular energy (>80%), are not sufficient to completely explain the AFP binding specificity.

Noninvasive estimation of pulmonary artery diastolic pressure in patients with tricuspid regurgitation by Doppler echocardiography

OBJECTIVES

The purpose of this study was to determine whether Doppler echocardiographic assessment of right ventricular pressure at the time of pulmonary valve opening could predict pulmonary artery diastolic pressure.

BACKGROUND

Doppler echocardiography has been used to estimate right ventricular systolic pressure noninvasively. Because right ventricular and pulmonary artery diastolic pressure are equal at the time of pulmonary valve opening, Doppler echocardiographic estimation of right ventricular pressure at this point might provide an estimate of pulmonary artery diastolic pressure.

METHODS

We studied 31 patients who underwent right heart catheterization and had tricuspid regurgitation. Pulmonary flow velocity was recorded by pulsed wave Doppler echocardiography, and tricuspid regurgitant velocity was recorded by continuous wave Doppler echocardiography. The time of pulmonary valve opening was determined as the onset of systolic flow in the pulmonary artery. Tricuspid velocity at the time of pulmonary valve opening was measured by superimposing the interval between the onset of the QRS complex on the ECG and the onset of pulmonary flow on the tricuspid regurgitant envelope. The tricuspid gradient at this instant was calculated from the measured tricuspid velocity using the Bernoulli equation. This gradient was compared to the pulmonary artery diastolic pressure obtained by right heart catheterization.

MEASUREMENTS AND RESULTS

The pressure gradient between the right atrium and right ventricle obtained at the time of pulmonary valve opening ranged from 9 to 31 mm Hg (mean, 19+/-5) and correlated closely with invasively measured pulmonary artery diastolic pressure (range, 9 to 36 mm Hg; mean, 21+/-7 mm Hg; r = 0.92; SEE, 1.9 mm Hg).

CONCLUSION

Doppler echocardiographic measurement of right ventricular pressure at the time of pulmonary valve opening is a reliable noninvasive method for estimating pulmonary diastolic pressure.

Power spectral analysis of heart period variability of preceding sinus rhythm before initiation of paroxysmal atrial fibrillation

Time domain analysis of heart period variability in patients without structural heart disease demonstrated increased parasympathetic modulation before paroxysmal atrial fibrillation (AF) occurring predominantly at night. However, diurnal differences in autonomic activity preceding AF episodes in a diverse patient population have not been assessed. Accordingly, we performed spectral analysis of heart period variability on Holter recordings during sinus rhythm preceding AF in 29 patients, 17 with night and 12 with day episodes. Samples taken 5, 10, and 20 minutes before AF onset were compared. Normalized high-frequency (HF) spectral power change was greater when comparing the interval 10 to 5 minutes with 20 to 10 minutes preceding AF in 26 of 29 patients (0.09 +/- 0.07 vs 0.03 +/- 0.02; p < 0.0001). HF spectral power increased before 3 of 12 AF episodes during the day compared with 15 of 17 AF episodes during the night (p = 0.001). Nocturnal AF episodes were preceded by increased HF spectral power in the 5- versus the 20-minute sample expressed as natural logarithm-transformed values (5.6 +/- 4.8 vs 4.2 +/- 4.0; p < 0.005) and normalized values (0.19 +/- 0.09 vs 0.10 +/- 0.07; p < 0.02), a decrease in low-frequency/HF ratio (1.05 +/- 0.61 vs 2.21 +/- 1.75; p < 0.05) and heart rate (60 +/- 13 vs 71 +/- 13 beats/min; p = 0.06). Structural heart disease was more common with daytime than nocturnal AF episodes (58% vs 18%, p < 0.05). In conclusion, HF spectral power change was increased preceding most AF episodes. However, diurnal differences were demonstrated. Contrary to daytime AF, increased parasympathetic activity preceded predominantly nocturnal AF, mostly in younger patients with structurally normal hearts.

Stage-specific expression of P2Y receptors, ecto-apyrase, and ecto-5'-nucleotidase in myeloid leukocytes

The expression of P2 purinergic receptor subtypes in leukocytes varies with both lineage and developmental stage. Given the recent identification and cloning of at least seven distinct G protein-coupled ATP receptor subtypes (P2Y family), we investigated P2Y receptor subtype expression during myeloid cell differentiation. We observed that KG-1 myeloblasts express P2Y1 but not P2Y2 receptors (previously termed P2U receptors), whereas later myeloid progenitors, including HL-60 promyelocytes and THP-1 monocytes, expressed P2Y2 but not P2Y1 receptors. In KG-1 cells, significant activation of Ca2+ mobilization by P2Y1 receptors was only observed after preincubation with potato apyrase, an exogenous ATPase. This indicated that P2Y1 receptors are desensitized in KG-1 cells by autocrine mechanisms that may involve enhanced release of endogenous nucleotides and/or decreased expression of cell-surface ecto-nucleotidases. We compared the levels of ecto-apyrase activity and expression in KG-1 myeloblasts and HL-60 promyelocytes. Extracellular ATP was rapidly metabolized by HL-60 but not by KG-1 cells. Reverse transcription-polymerase chain reaction analysis indicated that mRNA for CD39 (cluster of differentiation), an identified ecto-apyrase, was present in HL-60 but not KG-1 cells. Ecto-apyrase activity was modestly increased with differentiation of myeloid progenitors with either phorbol 12-myristate 13-acetate (PMA) or dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP). Differentiation of HL-60 cells with PMA, but not DBcAMP, strongly induced ecto-5'-nucleotidase activity and CD73 mRNA expression. These observations indicate that signal transduction by extracellular ATP in myeloid leukocytes can be regulated by developmentally programmed changes in the expression of P2Y receptor subtypes and multiple ecto-nucleotidases.

Detection of coronary collaterals using dipyridamole PET myocardial perfusion imaging with rubidium-82

This study evaluated the ability of dipyridamole PET myocardial perfusion imaging to detect coronary collaterals. A previous study showed an association between dipyridamole-induced coronary steal on PET imaging and the presence of coronary collaterals on angiography.

METHODS

Dipyridamole PET myocardial perfusion imaging using 82Rb was performed in 45 patients who had recent coronary angiography. The stress/rest count ratio (rubidium activity with stress divided by activity at rest)-was used to express the change in regional tracer uptake with dipyridamole and was calculated manually and automatically. The accuracy of the stress/rest count ratio for detecting coronary collaterals was determined.

RESULTS

A manual stress/rest count ratio < or = 0.80 identified coronary collaterals with 81% sensitivity, 92% specificity and 90% accuracy (p < 0.0001). An automated ratio < or = 0.80 had 90% sensitivity, 88% specificity and 90% accuracy (p < 0.0001). Vascular beds incorrectly identified by PET as having collaterals had an increased frequency of severe stenoses and abnormal wall motion.

CONCLUSION

PET perfusion imaging using the stress/rest count ratio can serve as a unique imaging method to identify coronary collaterals noninvasively.

Assessment of aortic regurgitation by color flow and continuous-wave Doppler echocardiography

This study describes a Doppler echocardiographic method for assessing the severity of aortic regurgitation based on the product of the velocity time integral and cross-sectional area of the aortic regurgitation jet. This method was found to be highly productive of the angiographic grade of aortic regurgitation with minimal overlap between grades.

Keratin 19 in paraffin sections of medullary carcinoma and other benign and malignant breast lesions

This investigation was aimed at studying the distribution of keratin 19 in various histological types of invasive breast carcinoma and benign breast lesions using two different antibodies, comparing the results, and assessing the significance of the finding. In particular, the usefulness of using the absence of keratin 19 immunostaining as a marker for medullary carcinoma was examined. Paraffin sections of 49 invasive breast carcinomas and 40 benign lesions were examined by the avidin-biotin complex immunoperoxidase technique using two commercially available keratin 19-specific monoclonal antibodies, BA17 and RCK 108. The results showed that the latter antibody stained more cases and the intensity of its staining was more pronounced than BA17. Most medullary and poorly differentiated invasive ductal carcinomas were BA17 negative and RCK108 negative or weakly positive. Moderately and well-differentiated ductal, invasive lobular, tubular, and most mucinous carcinomas were mostly positive with both antibodies, whereas a case of signet ring and a case of spindle cell carcinoma were negative with the two antibodies. Thirty eight of the 40 benign lesions examined showed variable numbers of positive cells, reflecting in general the pattern seen in normal ducts and acini. It is concluded that although keratin 19 seems to be completely absent or at most only weakly represented in paraffin sections of medullary carcinoma, similar reactions are obtained with poorly differentiated ductal tumors. Different antibodies may give different reactions, but well-differentiated ductal and invasive lobular tumors are usually more strongly stained, whereas signet ring and spindle cell carcinomas seem to be negative.(ABSTRACT TRUNCATED AT 250 WORDS)

Arrhythmogenic right ventricular dysplasia: a review

Arrhythmogenic right ventricular (RV) dysplasia is a predominant disorder of the RV, characterized by progressive replacement of myocardium by fibroadipose tissue and arrhythmic manifestations. It remains incompletely known despite the fact that it may cause sudden death, often exertional, in young and healthy individuals. The etiology is speculative and the disorder has autosomal dominant genetic predisposition. Commonly, the physical examination is unremarkable and the commonest abnormality on routine ECG is inverted T-waves on precordial leads. Morphologic abnormality of dysplastic RV can be detected by echocardiogram, radionuclear angiogram or contrast RV angiogram. They may miss cases with less involvement where gated MRI scans may be useful. Patients with syncope or symptomatic ventricular tachycardia have worse prognosis. Pharmacologic antiarrhythmic therapy is sometimes disappointing and various surgical and endocardial ablation procedures have been tried with varying success.

Preclinical evaluation of microencapsulated CFA/II oral vaccine against enterotoxigenic E. coli

Colonization Factor Antigen (CFA/II) from enterotoxigenic Escherichia coli (ETEC) prepared under good manufacturing practices (GMP) was successfully incorporated into biodegradable poly(D,L-lactide-co-glycolide) (PLGA) polymer microspheres (BPM) under GMP and found to be safe and immunogenic when administered intraduodenally to rabbits. Following vaccination, Peyer's patch cells responded by lymphocyte proliferation to in vitro challenge with CFA/II. Also, B cells secreting specific anti-CFA/II antibodies were found in spleens following vaccination. No pathological changes were found following total necropsies of ten rabbits vaccinated with CFA/II BPM. Sixty-three per cent of the CFA/II BPM were between 5 and 10 microns diameter by volume particle size distribution; 1.17% protein content; 2.15% moisture; < 0.01% acetonitrile; 1.6% heptane; 22 non-pathogenic bacteria and three fungi per 1 mg protein dose; and passed the general safety test. We conclude that the CFA/II BPM oral vaccine is immunogenic and safe to begin a Phase I clinical safety study following Investigational New Drug approval.

Acute myocardial infarction in a thirty-six year old postpartum female

A thirty-six year old woman who had an acute myocardial infarction during the early postpartum period is described. Review of literature on the incidence of postpartum myocardial infarction, the possible mechanisms and its clinical implications are summarized.

Cephalic fibromuscular dysplasia in 32 patients: clinical findings and radiologic features

The clinical and angiographic features of 32 patients with cephalic fibromuscular dysplasia (FMD) are reported. All of our patients were women, 78% of whom were between 41 and 70 years of age. At examination, 18 (56%) patients had the sudden onset of focal ischemic neurologic deficits. Seven (22%) patients had intracranial berry aneurysms, which ruptured in five patients but were asymptomatic in two. The most common angiographic pattern was the "string of beads" deformity, which involved both extracranial internal carotid arteries at or distal to the third cervical vertebral level. The vertebral artery was affected in six cases, while three cases had intracranial involvement. Less common angiographic findings in this series consisted of segmental fusiform dilation of the artery, and lesions in the form of a septum that extended across the lumen. Twelve patients were followed up for an average of four years. Progression of FMD lesions was shown in two of the six patients who had repeated angiograms. The literature contains reports of only nine cases of cephalic FMD with repeated angiograms, three of which demonstrated progression. Our experience suggests a beneficial role for surgery in patients with specific symptoms in the distribution of the affected vessel, when coexistent disease is negligible or absent.

High dose preoperative irradiation of the lower neck and supraclavicular fossae

Preoperative irradiation of 5,000 rad in 5 weeks before total laryngectomy with radical neck dissection was compared for two groups of patients: (1) those treated to a smaller volume through lateral opposed fields (37 patients) and (2) those treated to a larger volume by adding a third field directed to the lower neck and supraclavicular fossae (46 patients). There were no significant differences in tolerance to irradiation or in postoperative complications. However, locoregional tumor control improved significantly from 63% to 90% (P less than 0.02) with the three-field technique, and all four stomal recurrences were in the two-field group. Deaths from intercurrent disease and from distant metastases without local recurrence account for the failure to improve the overall survival rate.

Combination chemotherapy and radiotherapy in small-cell carcinoma of the lung

A combination of chemotherapy (Cytoxan, vincristine, and CCNU) and radiation therapy was used to treat 37 patients with small-cell carcinoma of the lung. There was 49% complete remission and an overall 76% objective response with an overall median survival of 12.5 months and 17 months for those showing a complete response. No serious morbidity was observed.