The Efficacy of Liposomal Bupivacaine in Regional Nerve Blocks for Below Knee Amputations

Postamputation pain is highly prevalent. Opioids are often utilized postoperatively; however, they have significant side effects. Liposomal bupivacaine (LB) was introduced to extend nerve blocks from hours into days. Regional nerve blocks with LB for below knee amputation (BKA) is a novel approach which may reduce opioid use after surgery. A retrospective review was conducted for patients who had received LB nerve blocks compared to none for postoperative pain control in BKAs. Daily average opioid consumption was evaluated from the time in postoperative acute care unit until day of discharge in oral morphine equivalents (OME). 69 patients who underwent below knee amputations were reviewed. The mean average daily OME was lower in the LB group compared to control group(25.0 vs 50.5 OME, respectively; P = .002) A higher percentage of patients in the study group were categorized in the minimal opioid use when compared to the control group LB regional nerve blocks for the BKA population are considered a novel approach in pain control. Our exploratory study shows that patients who received LB nerve blocks may have decreased opioid consumption after surgery.

A phase 1 study of ruxolitinib, steroids and lenalidomide for relapsed/refractory multiple myeloma patients

Ruxolitinib with lenalidomide and dexamethasone shows anti-myeloma effects in vitro and in vivo. MUC1 leads to lenalidomide resistance in multiple myeloma (MM) cells, and ruxolitinib blocks its expression. Thus, ruxolitinib may restore sensitivity to lenalidomide. A phase I trial was conducted to determine the safety and efficacy of ruxolitinib with lenalidomide and methylprednisolone for patients with relapsed/refractory (RR)MM who had been treated with lenalidomide, steroids and a proteasome inhibitor and showed progressive disease at study entry. A traditional 3 + 3 dose escalation design was used to enroll subjects in four cohorts. Subjects received ruxolitinib twice daily, lenalidomide daily on days 1-21 of a 28 day cycle and methylprednisolone orally every other day. Primary endpoints were safety, clinical benefit rate (CBR) and overall response rate (ORR). Forty-nine patients were enrolled. The median age was 64 years and they had received a median of six prior treatments including lenalidomide and steroids to which 94% were refractory. No dose limiting toxicities occurred. The CBR and ORR were 49% and 36%, respectively. All responding patients were refractory to lenalidomide. Grade 3 or 4 adverse events (AEs) included anemia (17%), decreased lymphocyte count (15%), and hypophosphatemia (10%). Most common serious AEs included sepsis (9.8%) and pneumonia (7.8%). This Phase I trial demonstrates that a JAK inhibitor, ruxolitinib, can overcome refractoriness to lenalidomide and steroids for patients with RRMM. These results represent a promising novel therapeutic approach for treating MM. NCT03110822.

A preliminary study of patient-specific differences in induced pluripotent stem cell-derived cardiomyocytes following hypoxia-induced injury

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Courtois Cardiovascular Signature Program

The increasing rate of cardiovascular disease (CVD) contributes to a worsening morbidity in the general population and a socioeconomic burden on the healthcare system. Newly approved therapies present unforeseen side effects and occasionally entail adverse cardiovascular responses in patients - this issue significantly stalls efficacious pharmacological development. Indeed, modern cardiovascular treatments do not account for the variability of individual patient reactions, due to a lack of a representative in vitro cardiac model. While the use of induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) has gained traction as a superior model for drug screening when compared to cardiac biopsies and immortalized cell lines, cardiovascular patient-specific differences remain poorly understood and understudied.

We hypothesized that 1) cardiomyopathic patient-derived iPSC-CMs have differing baselines of beating rate, contractility, viability, metabolic activity and protein expression, when compared to healthy controls, and that 2) cell lines have patient-specific responses to hypoxia-induced injury. As such, the purpose of this preliminary study was two-fold: 1) to perform a characterization of patient iPSC-CM function, and 2) to study patient-specific cellular responses to hypoxia.

First, we generated iPSC-CMs from the peripheral blood of donors (n=6 patients with cardiomyopathies, n=2 healthy donors). We then confirmed the expression of prominent cardiac markers connexin 43 (CXN43), sarcoendoplasmic reticulum Ca2+ ATPase (SERCA2a), GATA4 and cardiac Troponin T, as well as a lack of pluripotency markers Octamer-binding transcription factor 4 (OCT4), Nanog, Stage-specific embryonic antigen-4 (SSEA-4) and TRA-1-60 in the iPSC-CM lines, via immunocytochemistry. Preliminary assessment of iPSC-CMs (days 1-30 post-differentiation) revealed significant baseline differences in beating rate (p<0.01) and contractility amplitude (p<0.01) between iPSC-CMs derived from cardiomyopathic patients and healthy donors.

We then subjected iPSC-CM lines to hypoxic conditions (24 hours), to mimic ischaemic injury. Diseased patient-derived lines had significantly decreased viability and metabolic activity when compared to the controls, under normoxic (p<0.01) and hypoxic conditions (p<0.001). Immunoblotting revealed differential expression of cardiac markers and factors implicated in cardiac function, cardioprotection and pathology. Taken together, these results suggest that the detected differences at the cellular level after hypoxia-induced injury might be translatable to the inter-individual variability currently observed in the CVD patient population. The data gathered will prove to be instrumental in future studies of iPSC-CM responses to treatment. With this preliminary study, we hope to shift the focus towards these patient-specific differences at the cellular level, in the search for tailored therapies and a higher standard of care for CVD patients.

Comparison of the Impact of the Mediterranean Diet, Anti-Inflammatory Diet, Seventh-Day Adventist Diet, and Ketogenic Diet Relative to Cognition and Cognitive Decline

PURPOSE OF REVIEW

Increasing evidence points toward the importance of diet and its impact on cognitive decline. This review seeks to clarify the impact of four diets on cognition: the Mediterranean diet, the anti-inflammatory diet, the Seventh Day Adventist diet, and the Ketogenic diet.

RECENT FINDINGS

Of the diets reviewed, the Mediterranean diet provides the strongest evidence for efficacy. Studies regarding the anti-inflammatory diet and Seventh Day Adventist diet are sparse, heterogeneous in quality and outcome measurements, providing limited reliable data. There is also minimal research confirming the cognitive benefits of the Ketogenic diet. Increasing evidence supports the use of the Mediterranean diet to reduce cognitive decline. The MIND-diet, a combination of the Mediterranean and DASH diets, seems especially promising, likely due to its anti-inflammatory properties. The Ketogenic diet may also have potential efficacy; however, adherence in older populations may be difficult given frequent adverse effects. Future research should focus on long-term, well-controlled studies confirming the impact of various diets, as well as the combination of diets and lifestyle modification.

Use of serum B-cell maturation antigen levels to predict outcomes for myeloma patients treated with ruxolitinib, lenalidomide and methylprednisolone

Previous retrospective studies have shown that serum B-cell maturation antigen (sBCMA) levels predict outcomes among patients with multiple myeloma (MM) undergoing new treatments. Specifically, baseline levels and changes during treatment of this protein predict both progression free survival (PFS) and overall survival. However, prospective studies are lacking evaluating sBCMA for determining outcomes among MM patients undergoing new treatments. Thus, we evaluated whether its baseline levels and changes during treatment in the amount of this serum marker predict outcomes among 38 relapsed/refractory MM patients treated with ruxolitinib, lenalidomide and methylprednisolone in a phase 1 trial. Patients with baseline sBCMA levels in the lowest three quartiles had longer PFS (median PFS 136 vs. 28 days; p < 0.0001). This was also shown for patients with baseline levels below the median (median PFS 140 vs. 77 days; p = 0.0225). PFS was shorter for patients whose sBCMA levels increased ≥25% through their first cycle (median PFS: 50 vs. 134 days, p = 0.0022), second cycle (median PFS: 50 vs. 141 days, p = 0.0273), and during the first three cycles of study treatment (median PFS: 50 vs. 220 days, p < 0.0001). No patient whose sBCMA increased ≥25% during cycle 1 responded whereas the majority (58%) of patients whose level increased <25% responded. This is the first prospective study to determine whether sBCMA levels predict outcomes for MM patients undergoing a non-BCMA directed treatment regimen and demonstrates that baseline levels and its changes during treatment predict PFS and the likelihood of responding to their treatment. These results add to the growing literature suggesting that this serum marker will be useful for determining outcomes for patients undergoing treatment for MM.

Age Is But a Number: Damage Control Surgery Outcomes in Geriatric Emergency General Surgery

BACKGROUND

Damage control surgery (DCS) with temporary abdominal closure (TAC) is increasingly utilized in emergency general surgery (EGS). As the population ages, more geriatric patients (GP) are undergoing EGS operations. Concern exists for GP's ability to tolerate DCS. We hypothesize that DCS in GP does not increase morbidity or mortality and has similar rates of primary closure compared to non-geriatric patients (NGP).

METHODS

A retrospective chart review from 2014-2020 was conducted on all non-trauma EGS patients who underwent DCS with TAC. Demographics, admission lab values, fluid amounts, length of stay (LOS), timing of closure, post-operative complications and mortality were collected. GP were compared to NGP and results were analyzed using Chi square and Wilcox signed rank test.

RESULTS

Ninety-eight patients (n = 50, <65 y; n = 48, ≥65 y) met inclusion criteria. There was no significant difference in median number of operations (3 versus 2), time to primary closure (2.5 versus 3 d), hospital LOS (19 versus 17.5 d), ICU LOS (11 versus 8 d), rate of primary closure (66% versus 56%), post op ileus (44% versus 48%), abscess (14% versus 10%), need for surgery after closure (32% versus 19%), anastomotic dehiscence (16% versus 6%), or mortality (34% versus 42%). Average time until take back after index procedure did not vary significantly between young and elderly group (45.8 versus 38.5 h; P = 0.89). GP were more likely to have hypertension (83% versus 50%; P ≤ 0.05), atrial fibrillation (25% versus 4%; P ≤ 0.05) and lower median heart rate compared to NGP (90 versus 103; P ≤ 0.05).

CONCLUSIONS

DCS with TAC in geriatric EGS patients achieves similar outcomes and mortality to younger patients. Indication, not age, should factor into the decision to perform DCS.

Surgeons in surge - the versatility of the acute care surgeon: outcomes of COVID-19 ICU patients in a community hospital where all ICU patients are managed by surgical intensivists

Background

Reported characteristics and outcomes of critically ill patients with COVID-19 admitted to the intensive care unit (ICU) are widely disparate with varying mortality rates. No literature describes outcomes in ICU patients with COVID-19 managed by an acute care surgery (ACS) division. Our ACS division manages all ICU patients at a community hospital in New Jersey. When that hospital was overwhelmed and in crisis secondary to COVID-19, we sought to describe outcomes for all patients with COVID-19 admitted to our closed ICU managed by the ACS division.

Methods

This was a prospective case series of the first 120 consecutive patients with COVID-19 admitted on March 14 to May 10, 2020. Final follow-up was May 27, 2020. Patients discharged from the ICU or who died were included. Patients still admitted to the ICU at final follow-up were excluded.

Results

One hundred and twenty patients were included (median age 64 years (range 25–89), 66.7% men). The most common comorbidities were hypertension (75; 62.5%), obesity (61; 50.8%), and diabetes (50; 41.7%). One hundred and thirteen (94%) developed acute respiratory distress syndrome, 89 (74.2%) had shock, and 76 (63.3%) experienced acute kidney injury. One hundred (83.3%) required invasive mechanical ventilation (IMV). Median ICU length of stay (LOS) was 8.5 days (IQR 9), hospital LOS was 14.5 days (IQR 13). Mortality for all ICU patients with COVID-19 was 53.3% and 62% for IMV patients.

Conclusions

This is the first report of patients with COVID-19 admitted to a community hospital ICU managed by an ACS division who also provided all surge care. Mortality of critically ill patients with COVID-19 admitted to an overwhelmed hospital in crisis may not be as high as initially thought based on prior reports. While COVID-19 is a non-surgical disease, ACS divisions have the capability of successfully caring for both surgical and medical critically ill patients, thus providing versatility in times of crisis.

Level of evidence

Level V.

A Phase I Study of Ruxolitinib, Lenalidomide, and Steroids for Patients with Relapsed/Refractory Multiple Myeloma

PURPOSE

Ruxolitinib with lenalidomide and dexamethasone shows antimyeloma effects in vitro and in vivo. MUC1 leads to lenalidomide resistance in multiple myeloma cells, and ruxolitinib blocks its expression. Thus, ruxolitinib may restore sensitivity to lenalidomide. Therefore, a phase I trial was conducted to determine the safety and efficacy of ruxolitinib with lenalidomide and methylprednisolone for patients with relapsed/refractory multiple myeloma (RRMM) who had been treated with lenalidomide/steroids and a proteasome inhibitor and showed progressive disease at study entry.

PATIENTS AND METHODS

A traditional 3+3 dose escalation design was used to enroll subjects in four cohorts with planned total enrollment of 28 patients. Subjects received ruxolitinib twice daily, lenalidomide daily on days 1-21 of a 28-day cycle, and methylprednisolone orally every other day. Primary endpoints were safety, clinical benefit rate (CBR), and overall response rate (ORR).

RESULTS

Twenty-eight patients were enrolled. The median age was 67 years and received a median of six prior treatments including lenalidomide and steroids to which 93% were refractory. No dose-limiting toxicities occurred. The CBR and ORR were 46% and 38%, respectively. All 12 responding patients were refractory to lenalidomide. Grade 3 or grade 4 adverse events (AE) included anemia (18%), thrombocytopenia (14%), and lymphopenia (14%). Most common serious AEs included sepsis (11%) and pneumonia (11%).

CONCLUSIONS

This phase I trial demonstrates that a JAK inhibitor, ruxolitinib, can overcome refractoriness to lenalidomide and steroids for patients with RRMM. These results represent a promising novel therapeutic approach for treating multiple myeloma (ClinicalTrials.gov number, NCT03110822).

A phase I trial of ruxolitinib, lenalidomide, and methylprednisolone for patients with relapsed/refractory multiple myeloma (MM)

8048

Background: Preclinical studies from our laboratory have demonstrated that ruxolitinib (RUX) in combination with lenalidomide (LEN) and dexamethasone shows marked anti-myeloma effects both in vitro and in vivo. Furthermore, MUC1 is responsible for LEN resistance in MM cells, and RUX blocks its expression in MM cells. Thus, RUX may restore sensitivity to LEN. Therefore, a phase 1 trial was conducted to determine the safety and efficacy of RUX in combination with LEN and methylprednisolone (MP) for relapsed/refractory (RR) MM patients (pts) who had previously been treated with LEN/steroids and a proteasome inhibitor (PI) and showed progressive disease at study entry. Methods: A traditional 3+3 dose escalation design was used to enroll subjects in four cohorts with planned total enrollment to be 49 pts. Subjects received RUX twice daily continuously, LEN daily on d1-21 of a 28-d cycle and MP orally every other day. In DL0, pts received RUX 5 mg, LEN 5 mg, and MP 40 mg. In DL+1 and +2, both doses of LEN and MP remained unchanged and RUX was escalated to 10 and 15 mg, respectively. DL+3 escalated LEN to 10 mg with MP unchanged and RUX at 15 mg. Primary endpoints were safety, clinical benefit rate (CBR) and overall response rate (ORR). Results: As of September 1, 2018, 36 pts were enrolled, and 32 were evaluable for efficacy. The median age was 66 years (range, 46-81), and 21 (58%) were male. Pts received a median of 6 prior treatments including LEN and steroids to which they were all refractory and a proteasome inhibitor. No DLTs occurred, and DL+3 was expanded. Among evaluable pts, the CBR and ORR were 47% and 41%, respectively (1 CR, 2 VGPR, 10 PR and 2 MR), and 14 and 3 pts showed SD and PD. All 15 responding pts were refractory to LEN. G3 AEs included anemia (17%), neutropenia (14%), sepsis (14%), lymphocytopenia (11%), thrombocytopenia (11%), and pneumonia (11%). Most common SAEs included sepsis (14%) and pneumonia (11%). Conclusions: This Ph 1 trial demonstrates for the first time that a JAK inhibitor, RUX, can overcome refractoriness to LEN and steroids for RR MM pts. These promising results are leading to expansion of the current clinical trial to 78 pts, and represents a novel therapeutic approach for treating MM. Clinical trial information: NCT03110822.

Beyond the Chief Complaint: Our Patients' Worries

Fourth-year medical students at the University of Colorado School of Medicine distributed cards to patients in the emergency department asking, "What Worries You Most?" The patients' responses provided insight about their most pressing concerns, often unrelated to their "chief complaints."

Amyand's hernia presenting as an unusual inguinal mass: a case report

Accounting for approximately 0.4-0.6% of all inguinal hernias, Amyand's hernia is a rare condition in which a vermiform appendix is found in an inguinal hernia sac. It is most commonly found in males and in the pediatric population. Since Claudius Amyand's first reported case in 1736, there have only been a total of 228 documented cases of the Amyand's hernia. Due to its rarity, the pathophysiology and risk factors of the condition are still unclear. Some theorize that it is secondary to a patent processus vaginalis or perhaps the presence of a fibrous band between the hernia sac and testes. Amyand's hernia usually presents as an incarcerated or strangulated hernia, but its presentation can be quite variable. We report an unusual case of an Amyand's hernia presenting as an enlarging painful mass on the right lateral edge of the mons pubis, resembling an abscess.

Carbohydrate epitopes are immunodominant at the surface of infectious Neoparamoeba spp

Amoebic gill disease, the main disease of concern to the salmon industry in Tasmania, is caused by the amoeba, Neoparamoeba spp. Experimental infection can only be induced by exposure to wild-type (WT) parasites isolated from the gills of infected fish, as cultured amoebae are non-infective. To characterize the surface antigens of WT parasites, we produced monoclonal antibodies (mAbs) using subtractive immunization. Mice inoculated with non-infective parasites were treated with cyclophosphamide, to deplete reactive lymphocytes, and then immunized with different antigen preparations from infective parasites. When whole parasites were used for boosting, the percentage of WT unique mAbs was very high (86%) as was the percentage of mAbs specific for carbohydrate epitopes (89%). When deglycosylated membranes were used, the numbers of mAbs specific for non-carbohydrate epitopes did not increase, but the total number of WT unique mAbs was reduced (86-40%). Using an untreated membrane preparation, the total number of mAbs to surface molecules was very high, but all recognized carbohydrate epitopes. The total number of mAbs recognizing carbohydrate epitopes on the surface of the WT parasites was 97%, suggesting that the dominant epitopes on the surface molecules unique to WT parasites are carbohydrate in nature.

Toll-like receptor ligands and CD154 stimulate microglia to produce a factor(s) that promotes excess cholinergic differentiation in the developing rat basal forebrain: implications for neurodevelopmental disorders

Maternal inflammation plays a role in the etiology of certain neurodevelopmental disorders including autism and schizophrenia. Because maternal inflammation can lead to activation of fetal microglia, we have examined effects of inflamed microglia on cultured neural progenitors from rat embryonic septal region and basal forebrain. These cells give rise to cholinergic neurons projecting to cortex and hippocampus. Microglia stimulated with lipopolysaccharide (LPS), peptidoglycan, Poly I:C and CD154 produce conditioned media (CM) that promotes excessive numbers of cholinergic neurons and levels of choline acetyltransferase (ChAT) activity 6-8 times that of untreated cultures. Expression of the neural-specific transcription factor MATH1 increases substantially within 1 h of plating in LPS-CM. Untreated cultures do not attain equivalent levels until 6 h. By contrast, expression of glial-related transcription factors in LPS-CM-treated cultures never attains the elevated levels of untreated cultures. LPS-CM-treated clones derived from individual progenitors labeled with a LacZ-expressing retrovirus showed >2.5-fold increase in the percentage of cholinergic cells compared with untreated clones. Thus, CM from activated microglia prompts excess cholinergic differentiation from undifferentiated progenitors suggesting that microglial inflammation during critical stages can lead to aberrant brain development.

Selective plasma filtration for treatment of fulminant hepatic failure induced by D-galactosamine in a pig model

BACKGROUND

Plasma exchange may be useful for treating patients with fulminant hepatic failure but during the procedure growth factors that are important for hepatic regeneration are discarded. Addition of a selective plasma filter to the plasmapheresis circuit could eliminate protein bound toxic substances and retain growth factors for hepatic regeneration. This process is called selective plasma filtration.

AIMS

To determine if selective plasma filtration could be a useful treatment modality for fulminant hepatic failure.

METHODS

The system was tested in five groups of pigs with fulminant hepatic failure induced by galactosamine: group I, diseased control group (n=5); group II, sham control, (n=6); group III, plasma exchange (n=6); group IV, treatment with AC-1770 selective plasma filter (n=7); and group V, treatment with AC-1730 selective plasma filter which had a smaller pore size than AC-1770 (n=7). Fresh pig plasma was given to replace filtered plasma in pigs of groups III, IV, and V. Treatment was initiated 48 hours after administration of 0.75 g/kg galactosamine. The efficacy of selective plasma filtration was assessed by survival rate and improvement in haematological, biochemical, and immunohistological parameters.

RESULTS

Pigs treated with AC-1770 or AC-1730 selective plasma filters survived longer than the other groups (group I: 55 (10) hours; group II: 68 (7) hours; group III: 91 (10) hours; group IV: 269 (156) hours; group V: 950 (555) hours). One pig in group IV survived for 50 days; one pig in group V survived for 77 days and another pig in group V is still alive (>150 days). After treatment, plasma levels of aspartate aminotransferase, bilirubin, bile acid, ammonia, lactate dehydrogenase, and alpha-glutathione-S-transferase decreased. Substantial amounts of tumour necrosis factor alpha (TNF-alpha) and endotoxin were found in the filtrate. The selective plasma filtration groups retained significantly higher amounts of hepatocyte growth factor than plasma exchange alone. Similar TNF-alpha clearance was observed in the selective plasma filtration groups and the plasma exchange group. On day 4, significant improvement in liver function, as measured by the indocyanine green clearance test, was observed in groups IV and V but not in the other groups. A higher regeneration index of hepatocytes was also observed in the groups treated with AC-1770 and AC-1730 selective plasma filters.

CONCLUSION

Selective plasma filtration improved survival time and expedited liver regeneration in pigs with fulminant hepatic failure.

Evaluation of neurocardiac signals in pediatric patients with cyclic vomiting syndrome through power spectral analysis of heart rate variability

OBJECTIVE

To investigate autonomic regulation of neurocardiac signals in pediatric patients with cyclic vomiting syndrome (CVS).

METHODS

Fourteen patients with CVS, ages 3 to 16 years, were screened to eliminate any underlying cause for their symptoms, although 11 of the 14 patients had a history of migraine in the immediate family. Analysis of autonomic regulation was accomplished through power spectral analysis of the beat-to-beat heart rate variability signal. Data from affected patients were compared with data from 38 control subjects, ages 5 to 16 years, by a one-way analysis of variance. A measure of sympathovagal balance was obtained by computing a ratio of power in the low-frequency band (0. 02-0.15 Hz) to the power in the high-frequency band (0.15-0.4 Hz).

RESULTS

Pediatric patients with CVS have an elevated sympathetic modulation of the sinus node as represented by the low frequency/high frequency ratio (1.45 +/- 0.42 in patients vs 0.89 +/- 0.29 in healthy control subjects, P <.001).

CONCLUSIONS

The patients with CVS we studied have an autonomic imbalance with enhanced sympathetic and diminished parasympathetic vagal modulation of the heart.

A modified method of auxiliary partial liver transplantation in the rat

BACKGROUND/AIMS

In the animal model of auxiliary partial liver transplantation in the rat, the major problem is high outflow pressure since the direction of vascular outflow of the graft was perpendicular to that of the recipient inferior vena cava (IVC) and the anastomosis was far away from the right atrium. We aimed at developing an animal model that could prevent graft congestion.

METHODOLOGY

The graft contained the right lateral lobe and triangulated lobe of rat's liver. The modification of implantation included anatomizing an oblique cuff of IVC of donor graft into the recipient's IVC so that the size of anastomosis was large with an angle of 45 degrees and the resulting vascular outflow was no longer perpendicular to that of the recipient's IVC, and the creation of double grooves on the cuff body of the donor portal vein. Bile drainage was completed by inserting the bile duct (together with a stent) into the recipient's duodenum.

RESULTS

Congestion of grafts was not seen in 25 rats undergoing auxiliary partial liver transplantation using an oblique IVC graft. The 1-week and 2-week survival rates were 88% and 80%, respectively. In the group of rats (n = 10) operated on by using a straight IVC graft, graft congestion was seen and only 1 rat could survive over 1 day.

CONCLUSIONS

Modification of vascular outflow anastomosis prevented graft congestion and improved animal survival. The model may be useful for studying liver regeneration, transplantation immunology, and gene transfer.

[Enkephalinase activity in the guinea pig model of asthma]

Enkephalinase exists in airway epithelial cells, smooth muscle, and submucosa near glands, and cleaves tachykinins to inactive metabolites, thereby reducing there effects. To study the role of enkephalinase in asthmatic response, we measured its activity in guinea pig model of asthma. When compared with the control values, the enkephalinase activity was reduced during in immediate asthmatic response (IAR) and late asthmatic response (LAR). Compared with the control values (100%), each value was 79.7%, 73.4% in the trachea and 74.3%, 55.7% in the lung respectively. Tracheal muscle preparation taken from the control, IAR, and LAR groups were made and mounted in oxygenated modified Krebs-Ringer solution. The response was monitored by isometric transducer. Concentration response curves to NKA with or without phosphoramidon were obtained. The contractile responses of the LAR groups were enhanced in potency and efficiency. Phosphoramidon potentiated the NKA induced contraction of control and the IAR groups but was less potent in enhancing the contractile response in the LAR group, showing less enkephalinase activity in the LAR. These results suggest that the enkephalinase plays an important role in LAR. In LAR, the enkephalinase activity may be inhibited and the responsiveness of the smooth muscle to some bronchoconstrictor, such as tachykinins, may be increased.

Acute thallium poisoning: an evaluation of different forms of treatment

Hemodialysis, forced potassium diuresis, chelating agents per os, and Dithiocarb given intravenously during short periods of time were used for the treatment of acute thallium poisoning (ingestion of 750 mg of thallium sulfate), and the effectiveness of these different therapeutic procedures was analyzed. Chelating agents per os (Prussian blue, Dithiocarb, and Dithiozone) were ineffective in our patient, since fecal excretion of thallium was very low and unmodified by them. Forced potassium diuresis and hemodialysis were very useful therapeutic measures, especially in the first 12 days following ingestion. Dithiocarb perfusion seems to be the most effective method for enhancing urinary thallium excretion. This method might be most useful in the treatment of thallium poisoning if its deleterious effects could be eliminated.