Co-hydrothermal carbonization with process water recirculation as a valuable strategy to enhance hydrochar recovery with high energy efficiency

This study aims at valorizing the residual aqueous phase from hydrothermal carbonization (HTC) of Sicilian agro-wastes in order to enhance the hydrochar recovery, positively affecting the process energy balance. Process waters (PW) obtained from HTC and co-HTC using orange peel waste and fennel plant residues were used as recycled solvent in experiments carried out at the temperatures of 180 and 230 °C. The results showed that an additional hydrochar formation was promoted during recirculation of solvent, leading to average increments of solid mass yield of 10.5 wt% for tests conducted at 180 °C and 3.9 wt% for 230 °C. After five consecutive recirculation phases in co-HTC runs, the hydrochar yield increased up to 18.2 wt%. The low H/C and O/C atomic ratios values, found after recirculation, indicate that organic acids, accumulated in the PW, may catalyze the process and promote the biomass deoxygenation by boosting dehydration and decarboxylation. The recovered PWs from conversion steps with deionized water were also carbonized in absence of the solid feedstock in order to quantify their contribution in hydrochar formation during recirculation and thus the synergistic interactions. After recirculation, energy recovery averagely augmented by more than threefold, showing that the proposed strategy could significantly improve the sustainability of HTC.

Robotic-Assisted Rehabilitation for Post-Stroke Shoulder Pain: A Systematic Review

Post-stroke shoulder pain (PSSP) is a debilitating consequence of hemiplegia, often hindering rehabilitation efforts and further limiting motor recovery. With the advent of robotic-assisted therapies in neurorehabilitation, there is potential for innovative interventions for PSSP. This study systematically reviewed the current literature to determine the effectiveness of robotic-assisted rehabilitation in addressing PSSP in stroke patients. A comprehensive search of databases was conducted, targeting articles published up to August 2023. Studies were included if they investigated the impact of robotic-assisted rehabilitation on PSSP. The outcome of interest was pain reduction. The risk of bias was assessed using the Cochrane database. Of the 187 initially identified articles, 3 studies met the inclusion criteria, encompassing 174 patients. The reviewed studies indicated a potential benefit of robotic-assisted rehabilitation in reducing PSSP, with some studies also noting improvements in the range of motion and overall motor function. However, the results varied across studies, with some showing more significant benefits than others, because these use different protocols and robotic equipment.

Coexpression of ΔNp63/p40 and TTF1 Within Most of the Same Individual Cells Identifies Life-Threatening NSCLC Featuring Squamous and Glandular Biphenotypic Differentiation: Clinicopathologic Correlations

Introduction

Double occurrence of TTF1 and ΔNp63/p40 (henceforth, p40) within the same individual cells is exceedingly rare in lung cancer. Little is known on their biological and clinical implications.

Methods

Two index cases immunoreactive for both p40 and TTF1 and nine tumors selected from The Cancer Genome Atlas (TCGA) according to the mRNA levels of the two relevant genes entered the study.

Results

The two index cases were peripherally located, poorly differentiated, and behaviorally unfavorable carcinomas, which shared widespread p40 and TTF1 decoration within the same individual tumor cells. They also retained SMARCA2 and SMARCA4 expression, while variably stained for p53, cytokeratin 5, and programmed death-ligand 1. A subset of basal cells p40+/TTF1+ could be found in normal distal airways. Biphenotypic glandular and squamous differentiation was unveiled by electron microscopy, along with EGFR, RAD51B, CCND3, or NF1 mutations and IGF1R, MYC, CCND1, or CDK2 copy number variations on next-generation sequencing analysis. The nine tumors from TCGA (0.88% of 1018 tumors) shared the same poor prognosis, clinical presentation, and challenging histology and had activated pathways of enhanced angiogenesis and epithelial-mesenchymal transition. Mutation and copy number variation profiles did not differ from the other TCGA tumors.

Conclusions

Double p40+/TTF1+ lung carcinomas are aggressive and likely underrecognized non-small cell carcinomas, whose origin could reside in double-positive distal airway stem-like basal cells through either de novo-basal-like or differentiating cell mechanisms according to a model of epithelial renewal.

Reply to Fusco et al. Is Medication-Related Osteonecrosis of the Jaws (MRONJ) Associated to Cyclin-Dependent Kinase (CDK) 4/6 Inhibitors? A Word of Cautiousness. Comment on "Marcianò et al. Medication-Related Osteonecrosis of the Jaws and CDK4/6 Inhibitors: A Recent Association. Int. J. Environ. Res. Public Health 2020, 17, 9509"

We read the letter from Dr. Fusco and colleagues with great interest, and we would like to thank them for the stimulating comments regarding our paper "Medication-Related Osteonecrosis of the Jaws and CDK4/6 Inhibitors: A Recent Association" [...].

Reversible metamorphosis from Fe3O4 to FeO of epitaxial iron oxide films grown on the Fe-p(1 × 1)O surface

The reduction and oxidation of epitaxial Fe₃O₄ films grown by reactive deposition on a Fe-p(1 × 1)O surface have been investigated by means of Auger electron spectroscopy (AES), low energy electron diffraction (LEED) and scanning tunneling microcopy (STM). The as-grown iron oxide samples display a square LEED pattern with a lattice constant compatible with a p(1 × 1) bulk terminated Fe₃O₄(001) surface. STM topographic images of Fe₃O₄ are characterized by atomically flat terraces separated by highly oriented steps running along the (010) and (100) crystallographic directions of the substrate. Upon annealing at 800 K in an ultra-high vacuum, AES reveals that magnetite transforms to FeO. The sample exposes the (001) surface of the rock salt structure, with a lattice parameter close to that of bulk wüstite. The Fe₃O₄ phase can be recovered by oxidation at 10⁻⁶ mbar of molecular oxygen.

The reduction and oxidation of epitaxial Fe₃O₄ films grown by reactive deposition on a Fe-p(1 × 1)O surface have been investigated by means of surface science techniques.

New potential therapeutic-sequence strategies of TDM1 in the revolutionary era of metastatic HER2-positive breast cancer treatment: A monocentric retrospective experience

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Background: EMILIA study showed benefits in terms of both progression free survival (PFS) and overall survival (OS) administering Ado-trastuzumab emtansine (T-DM1) vs lapatinib-capecitabine in HER2+ mBC patients (pts) treated at least with a previous trastuzumab-taxane-based therapy. However a paucity of data is available on TDM1 efficacy after dual anti HER2 blockade with pertuzumab and trastuzumab (PT). Instead TH3RESA trial revealed the positive impact on OS of T-DM1 also in heavily pre-treated (at least 2 lines of T, lapatinib and taxanes regimens) pts. We conducted a retrospective analysis reporting innovative findings on the sequence of anti-HER2 treatments and how it could be potentially optimized. Methods: Between June 15, 2014 and January 31, 2020 we identified HER2+ (IHC: 3+ or 2+/FISH amplified) mBC pts treated with T-DM1, either as second-line after progression on dual blockade PT (Cohort PT) or after ≤ 3 anti her2-combined regimens (trastuzumab o lapatinib plus chemotherapy) (Cohort T). 74 pts received T-DM1: Cohort T n = 34 (all females, median age = 52,7), Cohort PT n = 40 (39 females, 1 male, median age = 52,2). Within Cohort T: 64,7 % of pts (n = 22) received T-DM1 after 1 previous anti her2-combined regimen, 20,6 % (n = 7) and 14,7 % (n = 5) in third and fourth lines, respectively. Instead, the whole Cohort PT received second line T-DM1 after pertuzumab/trastuzumab. Results: Median progression- free survival was 10,2 in Cohort T and 3,7 months in Cohort PT. As regards the best response rate, 8,8 % (n = 3/34) and 52,5 % (n = 21/40) of pts reported a progressive disease (PD) into the Cohorts T and PT, respectively: stable disease (SD) 38,2 % (n = 13/34) versus 15 % (n = 6/40); partial response (PR) 23,5 % (n = 8/34) vs 15 % (n = 6/40); complete response (CR) 23,5 % (n = 8/34) vs 12,5 % (n = 5/40). Almost 2/3 (n = 21/34) of Cohort T and half (n = 20/40) of Cohort PT pts had a 3+ IHC status. Conclusions: Our data suggest a lower efficacy of T-DM1 after progression on dual HER2-blockade PT. After all, EMILIA trial did not robustly evaluate the role of T-DM1 in this specific subset of pts. Obviously, larger prospective studies are necessary in order to optimize the best sequence strategy in the treatment of metastatic HER2+ BC, in light of the increasingly innovative anti-HER2 agents.

First case of 18F-choline uptake in acoustic schwannoma after stereotactic radiotherapy

A 69-year-old male patient, with bilateral hypoacusia and tinnitus, had a diagnosis of left vestibular schwannoma with synchronous meningioma on the left frontal lobe. After partial surgical resection of the acoustic schwannoma, this was followed by stereotactic radiosurgery on the residual lesion. The patient had a metachronous prostate cancer treated with conformal radiotherapy associated to 6 months of hormone therapy with luteinizing hormone/releasing hormone analog. During follow-up, prostate-specific antigen value increased to 0.27 ng/mL and the patient underwent 18F-methylcholine positron emission tomography/computed tomography (18F-choline PET/CT). The whole-body scan demonstrated a focus of increased uptake at level of the left cerebellopontine angle and at the left frontal lobe, corresponding to the known vestibular schwannoma and meningioma. A subsequent brain contrast-enhanced magnetic resonance imaging (MRI) showed an increased dimension of the left cerebellopontine neuroma and dimensional stability of the left frontal meningioma compared with previous MRI of 6 months earlier. To the best of our knowledge, we describe the first case of a 18F-choline PET/CT demonstrating a relapse of a vestibular schwannoma after stereotactic radiotherapy.

PCNA/Cyclin and P-Glycoprotein as Prognostic Factors in Locally Advanced Breast Cancer. An Immunohistochemical, Retrospective Study

Aims and Background

The aim of the present study was to determine, retrospectively, whether the immunohistochemical expression of two biologic markers of aggressivity, P-glycoprotein (P-gp) and PCNA/cyclin (PCNA), could be related to response to chemotherapy and prognosis in locally advanced breast cancer.

Methods

PC 10 Mab was used to determine the proliferation index (PCNA) and C-219 Mab to determine P-gp in 25 locally advanced breast carcinomas subjected to preoperative chemotherapy with MDR-related drugs.

Results

P-gp and PCNA were expressed in 76 % and 100 % of the tumors, respectively. No case of high P-gp expression was associated with good chemosensitivity, and all P-gp-negative cases showed the best chemotherapeutic response. P-gp and PCNA were both highly expressed in patients who developed local-regional or distant metastases. No recurrence was associated with a negative or low P-gp score.

Conclusions

Statistical analysis showed that high P-gp expression was related to a poor response to chemotherapy and a short disease-free survival. A high PCNA score was not found to be significant for predicting chemosensitivity or survival.

Clinical-statistical Correlation in 286 Cases of Diffuse and Intestinal Carcinoma of the Stomach

286 gastric carcinoma cases have been classified according to Lauren's system. The intestinal and diffuse histotypes are compared, and correlated with the epidemiologic data, type of operation and follow-up. The results show that total gastrectomy is indicated in diffuse carcinoma.

The comparison of outcomes from tyrosine kinase inhibitor monotherapy in second- or third-line for advanced non-small-cell lung cancer patients with wild-type or unknown EGFR status

BACKGROUND

Second-line treatment for advanced non-small-cell lung cancer (NSCLC) patients includes monotherapy with a third-generation cytotoxic drug (CT) or a tyrosine kinase inhibitor (TKI). These options are the actual standard for EGFR wild-type (WT) status, as patients with EGFR mutations achieve greater benefit by the use of TKI in first-line treatment. Some clinical trials and meta-analyses investigated the comparison between CT and TKI in second-line, but data are conflicting.

METHODS

We designed a retrospective trial to gather information about TKI sensitivity in comparison with CT. We selected from clinical records patients treated with at least 1 line of CT and at least 1 line of TKI. We collected data about age, sex, performance status, comorbidity, smoking status, histotype, metastatic sites, EGFR status, treatment schedule, better response and time-to-progression (TTP) for each line of treatment and overall survival (OS).

RESULTS

93 patients met selection criteria. Mean age 66,7 (range: 46-84). M/F ratio is 3:1. 39 EGFR-WT and 54 EGFR-UK. All patients received erlotinib or gefitinib as second-line treatment or erlotinib as third-line treatment. No TTP differences were observed for both second-line (HR:0,91; p = 0,6333) and third-line (HR:1.1; p = 0,6951) treatment (TKI vs CT). A trend of a benefit in OS in favor of 3rd-line TKI (HR:0,68; p = 0,11).

CONCLUSIONS

This study explores the role of TKIs in EGFR non-mutated NSCLC patients. OS analysis highlights a trend to a benefit in patients who received TKI in third-line, even if this result is statistically non-significant. Further analysis are needed to find an explanation for this observation.

Cervical dystonia patients display subclinical gait changes

INTRODUCTION

Gait disorders in cervical dystonia (CD) are reported in patients under DBS or in severe cases complicated with spinal deformities.

OBJECTIVE

to assess walking motor pattern in CD patients without DBS and not presenting scoliosis.

METHODS

Computerized gait analysis (CGA) was performed in CD patients, before and after botulinum toxin (BoNT) injections, and in healthy controls (HC). Spatiotemporal (ST) parameters were compared between CD and HC groups. Correlation analysis was conducted between ST parameters and clinical features of CD patients.

RESULTS

CD patients demonstrated a significant reduction of velocity, stride length, % of swing phase, and dynamic stability index while stride and swing time were increased. No significant effect of BoNT was detected. A significant inverse correlation was found between TWSTRS and stride length.

CONCLUSION

CD patients may have a slow gait with subclinical evidence. Our data suggest this alteration might be an endophenotipic feature of CD.

Salivary miRNA-210 involvement in medication-related osteonecrosis of the jaws

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Background: Improved survival rates from cancer have increased the need to understand the health related problems of cancer treatment. Persistent oral health related problems significantly affect patient's quality of life. Medication-related osteonecrosis of the jaws (MR-ONJ) is an oral complication of antiresorptive medications, denosumab and other medications that target angiogenesis for the management of metastatic bone cancer. The purpose of this pilot study, is to investigate, for the first time, microRNAs expression in MR-ONJ. Recent studies reported the miRNA-210 (a specific angiogenic-related miRNA) demethylation in the Osteonecrosis of the Femoral Head. We hypothesized that MiRNA-210 could also be involved in MR-ONJ development. Primary objective of the study is to investigate the role of miRNA-210 in MR-ONJ pathogenesis. Secondary objective is to investigate the feasibility of salivary miRNAs detection as potential non invasive biomarkers for MR-ONJ. Methods: A case-and-control study has been designed. Inclusion criteria are malignant tumors with ongoing treatment or previous history of anti-resorptive or anti-angiogenic medications. The predictor variable is the presence or absence of MR-ONJ. Oral examination and dental x-ray examinations suggestive of MR-ONJ will be performed. Saliva sample will be collected according to the protocol by Navazesh. The methylation status of miRNA-210 will be investigated using quantitative PCR (Q-PCR). Values will be compared between case and control group. Results: The main expected results are to enroll approximatively twenty patients in case group and sixty patients in control group within a one year recruitment period, validate that saliva is a medium for the identification of biomarkers associated with MR-ONJ and confirm the hypothesis that miRNA-210 is involved in MR-ONJ development. Conclusions: Results acquired within this project would represent a contribute to the understanding of the molecular mechanisms driving to the development of MR-ONJ lesions. MiRNA-210 demethylation could serve as a potential therapeutic target for the treatment of MR-ONJ through stimulation of angiogenesis.

A decade of EGFR inhibition in EGFR-mutated non small cell lung cancer (NSCLC): Old successes and future perspectives

The discovery of Epidermal Growth Factor Receptor (EGFR) mutations in Non Small Cell Lung Cancer (NSCLC) launched the era of personalized medicine in advanced NSCLC, leading to a dramatic shift in the therapeutic landscape of this disease. After ten years from the individuation of activating mutations in the tyrosine kinase domain of the EGFR in NSCLC patients responding to the EGFR tyrosine kinase inhibitor (TKI) Gefitinib, several progresses have been done and first line treatment with EGFR TKIs is a firmly established option in advanced EGFR-mutated NSCLC patients. During the last decade, different EGFR TKIs have been developed and three inhibitors have been approved so far in these selected patients. However, despite great breakthroughs have been made, treatment of these molecularly selected patients poses novel therapeutic challenges, such as emerging of acquired resistance, brain metastases development or the need to translate these treatments in earlier clinical settings, such as adjuvant therapy.

The aim of this paper is to provide a comprehensive review of the major progresses reported so far in the EGFR inhibition in this molecularly-selected subgroup of NSCLC patients, from the early successes with first generation EGFR TKIs, Erlotinib and Gefitinib, to the novel irreversible and mutant-selective inhibitors and ultimately the emerging challenges that we, in the next future, are called to deal with.

Electron spectroscopy investigation of the oxidation of ultra-thin films of Ni and Cr on Fe(0 0 1)

We investigated the room temperature oxidation of ultra-thin Ni and Cr films grown on Fe(0 0 1). In particular, we characterized the degree of crystallinity and the stoichiometry of the oxide layers and addressed the chemical stability of the interface with the highly reactive Fe substrate by means of low-energy electron diffraction and x-ray and UV photoemission spectroscopy. In the Ni case we detected, upon oxidation, the formation of a Fe(3)O(4) layer covering the Ni oxide, due to the diffusion of Fe cations towards the surface. At high temperature and in ultra-high vacuum conditions, the Ni oxide dissolved and the Fe oxide layer was reduced to FeO. In the Cr case, we observed the formation of a thin Cr(2)O(3) oxide layer, showing a diffraction pattern compatible with a defective γ-Cr(2)O(3) phase. A thicker Cr oxide layer could be produced by oxidizing the sample at 300 °C, at the expense of the incorporation of trace amounts of Fe cations.

Enhanced atom mobility on the surface of a metastable film

A remarkable enhancement of atomic diffusion is highlighted by scanning tunneling microscopy performed on ultrathin metastable body-centered tetragonal Co films grown on Fe(001). The films follow a nearly perfect layer-by-layer growth mode with a saturation island density strongly dependent on the layer on which the nucleation occurs, indicating a lowering of the diffusion barrier. Density functional theory calculations reveal that this phenomenon is driven by the increasing capability of the film to accommodate large deformations as the thickness approaches the limit at which a structural transition occurs. These results disclose the possibility of tuning surface diffusion dynamics and controlling cluster nucleation and self-organization.

Apelin beyond kidney failure and hyponatremia: a useful biomarker for cancer disease progression evaluation

Apelin regulates angiogenesis, stimulating endothelial cell proliferation and migration. It is upregulated during tumor angiogenesis, and its overexpression was reported to increase tumor growth. Furthermore, apelin controls vasopressin release and body fluid homeostasis. The aim of this study was to examine the correlations between apelin expression and clinical outcomes in oncologic patients, such as cancer disease progression and patient's survival. Apelin levels were evaluated in a cohort of 95 patients affected by different varieties of cancer. Partial remission and stable disease were assigned to the 'no progression' group, comparing it with the progressor group. Patients were followed up for 2 years. Receiver operating characteristics analysis was employed for identifying the progression of the oncologic disease and Kaplan-Meier curves assessed the survival. Adjusted risk estimates for progression endpoint were calculated using Cox proportional hazard regression analysis. Oncologic patients had higher apelin levels compared with healthy subjects, and apelin was closely related to the stages of the disease. In the hyponatremia group, apelin values were significantly higher than patients with eunatremia. After the follow-up of 24 months, 41 patients (43%) reached the endpoint. Progressor subjects presented significantly increased apelin values at baseline compared with non-progressor. Univariate followed by multivariate Cox proportional hazard regression analysis showed that apelin predicted cancer progression independently of other potential confounders. In patients with cancer, apelin closely reflects the stage of the disease and represents a strong and independent risk marker for cancer progression.

A static diagnostic biopsy in patients with mutated EGFR lung adenocarcinom to guide therapeutic decisions

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Background: Approximately 70% of the pts. whose lung cancers harbor EGFR mutations acquire drug resistence after a response to EGFR tyrosine kinase inhibitors (TKIs) treatment; this acquired resistance is mainly due to a secondary mutation in EGFR (T790 M) in about 50% of patients, amplification of MET in 15%, PIK3CA mutations in 5%, an unknown mechanism in almost 30%, and SCLC transformation in some patients. Furthermore, clinical experience revealed that cancers with acquired resistance can respond again to TKIs, after a drug-free interval. To aid in identification and treatment of these patients we examined a cohort of patients whose cancers were assessed with tumor biopsies at multiple times before and after their treatment with TKIs. Methods: 21 lung adenocarcinomas pts. (10 male, 11 female, median age 53 years) with EGFR mutations at 19 or 21 exons received TKIs, as first line of treatment. All showed a clinical response and all relapsed ( mTTP 10 months). At the time of relapse a new biopsy was performed, histologic samples were reviewed to re-confirm the diagnosis, EGFR and MET amplification were identified by FISH, while EGFR mutations have been tested by DNA sequencing. Results: At the time that drug resistence was acquired all pts. retained their original activating EGFR mutations, 9 pts. developed EGFR T790M resistance mutation with pronunced EGFR amplification in 3, 2 pts. developed MET amplification, 8 biopsies did not reveal any new mutations, two pts. were found to have a diagnosis of small cell lung cancer in their drug resistant tumor biopsies and responded well to conventional chemotherapy regimen.15 of 19 confirmed lung adenocarcinoma patient underwent to a cisplatin - pemetrexed chemotherapy regimen and at the time of progression 10 of them accepted to undergo a new biopsy. Three pts. ( after 4, 5 and 6 months break from treatment with TKIs ) lost T790M mutation and their disease responded to a second-line course of erlotinib. Conclusions: In our cohort of pts. with acquired EGFR resistence some patients lost acquired T790M mutation and become sensitive to EGFR inhibitor, in addition, two pts. underwent the histologic transformation from NSCLC to SCLC at the time of TKI resistence.

High-intensity focused ultrasound as an alternative to the surgical approach in primary hyperparathyroidism: a preliminary experience

BACKGROUND

Surgery is the therapy of choice in primary hyperparathyroidism (PHPT), although other less invasive techniques have been used in the attempt to cure the disease. Recently, high-intensity focused ultrasound (HIFU), a totally non-invasive technique, has become available to cure solid tumors.

AIM

The aim of this pilot study has been to assess the safety and efficacy of HIFU in symptomatic patients with PHPT.

MATERIAL AND METHODS

Four out of 31 patients with surgical indications within a cohort of 47-screened patients with PHPT were considered eligible for the study. All patients accepted to participate and were submitted to HIFU treatment in a single session. One patient was submitted to surgery after HIFU treatment. Patients were followed-up for 12 months after the procedure.

RESULTS

A persistent or a partial remission of the disease, respectively, were obtained in 2 patients (50%), including the one who underwent surgery after HIFU treatment. Safety was assessed performing laryngoscopy in all patients after HIFU procedure. A transient vocal cord paralysis was observed in all patients treated by HIFU only. No permanent side effects were observed in the long term.

CONCLUSIONS

HIFU might be a promising technique in treating PHPT, provided that further development of the software decreases the rate of side effects and improves the short- and long-term efficacy.

The impact of thyroidectomy on parathyroid glands: a biochemical and clinical profile

INTRODUCTION

An evaluation of PTH levels during thyroid surgery may reflect the functional status of the parathyroids and be useful in identifying patients at risk for hypocalcemia. This study aims to monitor the parathyroid function during total thyroidectomy through intra-operative serial samples for calcium and PTH.

MATERIALS AND METHODS

Forty-seven patients undergoing total thyroidectomy for different diseases were selected for the study. Patients underwent serum PTH and calcium sampling at the induction of anesthesia (T0) and after the first (T1) and the second (T2) lobectomy. Serum calcium was also drafted 24 h after the operation.

RESULTS

Mean PTH at T0, T1, and T2 was, respectively: 32.1 pg/ml, 19.6 pg/ml, and 11.5 pg/ml. PTH was significantly higher at T0 when compared to T1 (p<0.0001). It was also significantly higher at T1 than at T2 (p<0.0001). At T1 PTH levels were below the normal range in 20/47 cases (42.5%) and at T2 in 31/47 cases (66%). Twenty-four h after surgery, 8 patients (17%) demonstrated a biochemical hypocalcemia. A PTH value at T0 in the upper (>70 pg/ml) or in the lower (<20 pg/ml) limits of the normal range was statistically related to post-operative hypocalcemia (p=0.017).

DISCUSSION

The study seems to confirm that serum PTH during thyroidectomy does not represent a sensitive tool in precociously identifying hypocalcemic patients. Nevertheless, before surgery, a PTH concentration at the higher or lower normal limit may help to identify patients "at risk" of developing hypocalcemia.

Limits and drawbacks of video-assisted parathyroidectomy

BACKGROUND

Minimally invasive video-assisted parathyroidectomy (MIVAP) is a novel minimally invasive approach to primary hyperparathyroidism (PHPT). It is a gasless operation characterized by a single central incision and external retraction. This paper describes the drawbacks and limitations of this procedure based on a 5-year experience and 260 operations.

METHODS

Of 364 patients with PHTP, 260 were selected for MIVAP. In most patients a unilateral minimally invasive exploration was performed.

RESULTS

MIVAP was carried out successfully in 239 patients with a mean operating time of 40 (range 20-180) min. Conversion to cervicotomy was required in 21 patients (8.1 per cent). Complications included recurrent nerve palsy in two patients (0.8 per cent), haemorrhage that required reoperation 6 h after parathyroidectomy in one patient (0.4 per cent) and transient hypoparathyroidism in six patients (2.5 per cent). In five patients (2.1 per cent) persistent PHPT developed shortly after surgery.

CONCLUSION

After 5 years of experience, MIVAP appears to be feasible, safe and applicable to the majority of patients with PHPT.

Calcium-sensing receptor gene polymorphisms in primary hyperparathyroidism

The calcium-sensing receptor (CaR) polymorphism A986S has been found to be associated with higher serum calcium levels in normal subjects, suggesting that this amino acid change might decrease the inhibitory activity of the mutated receptor, render the parathyroid cells more prone to proliferate, and eventually increase the risk of developing primary hyperparathyroidism (PHPT). The aim of the present study was to investigate the frequency of this and other 2 known CaR polymorphisms (R990G and Q1011 E) in patients with PHPT and their effect on its phenotype. We studied 103 Italian patients with PHPT and 148 healthy Italian subjects and we compared the results in 50 pairs matched for sex, age and geographic provenience. A fragment of exon 7 of the CaR gene, containing the 3 polymorphic loci of interest (A986S, R990G, and Q1011E), was amplified by PCR and sequenced. Serum calcium and PTH levels, BMD and other biochemical and clinical parameters were evaluated. The frequency distribution of the A9865, R990G, and Q1011 E polymorphisms in the 103 PHPT patients was 39.8%, 5.8%, and 2.0%, respectively. There was no difference in the frequency of the 3 CaR polymorphisms in the 50 matched pairs of patients and controls. We found no significant difference in several clinical and biochemical parameters between PHPT patients carrying or not the 986S allele. Finally, no relationship was observed between the 986S genotype and total and ionized serum calcium in control subjects. The A986S CaR polymorphism is the most common in Italian PHPT patients and the allotype AS does not appear to play a relevant role in the pathogenesis of PHPT and its severity. The A986S polymorphism does not correlate with serum calcium levels in normal Italian subjects.

A quick intraoperative parathyroid hormone assay in the surgical management of patients with primary hyperparathyroidism: a study of 206 consecutive cases

OBJECTIVE

The traditional surgical approach for patients with primary hyperparathyroidism (PHPT) consists of the identification of at least four glands and in the removal of all hyperfunctioning parathyroid tissue.

DESIGN

To evaluate whether intraoperative parathyroid hormone (PTH) monitoring will allow a more limited surgical procedure by confirming complete removal of all hyperfunctioning tissue.

METHODS

Plasma samples were obtained from 206 consecutive patients with sporadic PHPT before skin incision, during manipulation of a suspected adenoma, and 5 min (T-5) and 10 min after removal of abnormal parathyroid tissue. PTH was measured by a quick immunochemiluminescent assay (QPTH). The operative success was defined by a decrease of PTH greater than 50% of the highest pre-excision value.

RESULTS

A >50% decrease of PTH occurred in 203 patients and was evident at T-5 in the majority of cases. All but three had normal serum calcium the day after surgery and afterwards. PTH concentration did not show a >50% decrease in the remaining three cases after completion of surgery. One patients had negative neck exploration and remained hypercalcemic; the other two had normal serum calcium at follow-up. Thus, the intraoperative QPTH correctly predicted the outcome of surgery in 201 patients (97.5%) (200 true positive and 1 true negative), and provided three false positive and two false negative results.

CONCLUSIONS

The intraoperative QPTH measurement represents a useful tool to assist the surgeon during parathyroidectomy. It indicates whether all hyperfunctioning parathyroid tissue has been removed, limiting the procedure to a unilateral neck exploration in most cases.

MEN1 gene alterations do not correlate with the phenotype of sporadic primary hyperparathyroidism

Loss of heterozygosity (LOH) in the MEN1 region on chromosome 11q13 and MEN1 gene mutations have been found in a subset of sporadic parathyroid tumors. The question of whether these genetic abnormalities in the parathyroid tumors might influence the clinical and biochemical characteristics of primary hyperparathyroidism (PHPT) remains to be elucidated. The aim of the present study was to correlate the presence of MEN1 gene alterations in PHPT tumors with the clinical phenotype. Using microsatellite analysis for LOH at 11q13 and DNA sequencing of the coding exons, the MEN1 gene was studied in 38 parathyroid tumors of patients with sporadic PHPT. Fourteen tumors showed LOH at 11q13, and mutations of MEN1 gene were detected in 7 cases. The clinical and biochemical characteristics of patients were unrelated to the presence or absence of LOH and/or MEN1 gene mutations. In conclusion, MEN1 gene alterations are rather common in sporadic PHPT and their presence does not correlate with the clinical manifestations of the disease.

Evidence of increased matrix metalloproteinase-9 concentration in patients following cardiopulmonary bypass

Cardiopulmonary bypass (CPB) is associated with a systemic inflammatory response, which can result in acute lung injury known as "postperfusion syndrome." Neutrophil activation with concomitant serine protease release has been implicated in the pathogenesis of "postperfusion syndrome." Increased plasma levels of neutrophil elastase (NE) have been demonstrated in patients undergoing CPB, and it is well documented that both NE and matrix metalloproteinase-9 (MMP-9) have a synergistic role in pulmonary injury. We, therefore, hypothesized that plasma levels of MMP-9 would be elevated in patients after CPB. Human plasma was obtained after informed consent from eight patients undergoing CPB. Plasma was collected at the start of CPB, 5 minutes after the initiation of CPB, and at the termination of CPB (156 +/- 17 min). All samples were analyzed by both standard enzyme-linked immunosorbent assay (ELISA) and gelatin zymography for MMP-9 (free and total enzyme) concentration. Data were expressed as means +/-SE and assessed by analysis of variance (ANOVA). Plasma MMP-9 concentration was significantly increased at the end of CPB (191 +/- 30.4 ng/mL; p <.05) as compared to both the start of CPB (28.3 +/- 13.2 ng/mL) and 5 minutes after the initiation of CPB (44.3 +/- 15.4 ng/mL). Patients undergoing CPB show an increase in serum MMP-9 levels. Prior studies utilizing an animal model of "postperfusion syndrome" have shown that inhibition of MMP-9 and NE prevented pulmonary injury following CPB. The results of the current study suggest that such an approach may also have merit in the clinical setting of cardiopulmonary bypass.

Parathyroid expression of calcium-sensing receptor protein and in vivo parathyroid hormone-Ca(2+) set-point in patients with primary hyperparathyroidism

A reduced expression of calcium-sensing receptor (CaR) messenger ribonucleic acid and protein accompanied by abnormalities in parathyroid cell proliferation and PTH secretion are present in primary hyperparathyroidism. We studied the expression of CaR protein by immunohistochemistry in 36 sporadic parathyroid adenomas and investigated the relationship between CaR expression and several preoperative clinical parameters, including the set-point of Ca(2+)-regulated PTH secretion (measured in vivo). The adenomas were classified in 4 categories according to the intensity of immunohistochemical staining: 5 (14%) showed a CaR staining intensity similar to that of normal parathyroid ( ), 10 (27%) showed moderate staining (++), 16 (45%) showed weak staining (+), and 5 (14%) were negative (-). The intensity of CaR staining was not related to preoperative serum Ca(2+), PTH levels or adenoma volume. Twenty-nine patients underwent preoperatively the calcium infusion test to evaluate the PTH-Ca(2+) set-point. Individual values of PTH-Ca(2+) set-point ranged from 1.38-1.93 mmol/L and were significantly correlated with basal Ca(2+) levels (r = 0.96; P: = 0. 0001) and adenoma volume (r = 0.5; P: = 0.01). The mean PTH-Ca(2+) set-point values were significantly different in the 4 groups of patients classified according to immunohistochemical staining intensity of their adenoma (P: = 0.025; F = 3.78); the mean PTH-Ca(2+) set-point was significantly higher in the groups classified as negative than in those classified as weak or moderate. No correlation was observed between the PTH-Ca(2+) set-point and basal PTH levels or between the percent maximal PTH inhibition and adenoma volume and basal PTH or Ca(2+) levels. In summary, our data suggest that there is a relationship between apparent CaR protein expression and PTH-Ca(2+) set-point abnormality, suggesting that a reduced receptor content might have an important role in the pathogenesis of primary hyperparathyroidism.

Six novel MEN1 gene mutations in sporadic parathyroid tumors

We report nine mutations of the multiple endocrine neoplasia type 1 (MEN1) gene in sporadic parathyroid adenomas. Six of them have not previously been described: E60X, P32R, 261delA, 934+2T-->G, S443P, and 1593insC. The tissue samples were initially submitted to LOH analysis at 11q13 followed by SSCP screening of LOH-positive samples. Mutations were identified by direct sequencing and subcloning. Three (E60X, P32R, and 261delA) were in exon 2, one (934+2bp) in the splice junction of exon 5, one (S443P) in exon 9, and one (1593insC) in exon 10. The 3 mutations in exon 2 were associated with loss and/or creation of a restriction site. The corresponding germline sequence of the MEN1 gene was normal. Most mutations would likely result in a nonfunctional menin protein, and therefore in the loss of a tumor suppressor protein.

Systemic inflammation induced by cardiopulmonary bypass: a review of pathogenesis and treatment

The acute respiratory distress syndrome (ARDS) is a severe alteration in lung structure and function that develops secondary to a traumatic stimulus. When ARDS develops following cardiopulmonary bypass (CPB) it is know as postpump syndrome (PPS). ARDS can be caused by a single massive insult ("hit"); however, sequential minor insults ("hits") are more common clinically. The concept of multiple sequential insults causing ARDS has been termed the "two-hit" model of ARDS. The purpose of this article is to summarize our studies testing the hypothesis that PPS is caused by multiple sequential insults. To confirm our hypothesis, we developed a porcine model of "two-hit" PPS. Our model was composed of sequential benign insults, with CPB as the "first hit" and low dose of endotoxin as the "second-hit." It is our hypothesis that the mechanism of PPS is CPB-induced priming of polymorphonuclear leukocytes (PMNs) ("first-hit") with subsequent PMN activation by a second insult ("second-hit") such as endotoxin. Our model confirms this clinically relevant postulate, and we provide strategies to disrupt the inflammatory cascade leading to PPS.

[Video-assisted parathyroidectomy: a series of 85 cases]

AIM OF THE STUDY

To verify the feasibility of video-assisted parathyroidectomy, set up the indications and report the results in a series of 85 patients.

MATERIAL AND METHODS

From 1997 to 1999, 85 patients affected by primary hyperparathyroidism due to single gland disease, with an adenoma smaller than 35 mm as demonstrated by preoperative imaging, were referred for video-assisted parathyroidectomy. There were 62 females and 23 males. Mean age was 53 years, (range 23-82). Video-assisted parathyroidectomy was associated with intra-operative PTH quick-assay. Calcium testing was controlled before leaving the hospital, 1 month and 3 months later, and postoperative laryngoscopy was performed in all patients.

RESULTS

There were five conversions to open cervicotomy: three due to a contra-lateral second adenoma, two because of an intrathyroidal adenoma. The mean operative time for video-assisted procedure was 59 minutes (range: 25-180). Circulating PTH levels 10 minutes after the removal of the affected gland(s) always dropped significantly, and pathological report confirmed the parathyroid nature of the specimens (mean diameter 13 mm, range 7-35). Morbidity consisted of five cases of transient hypocalcemia and one permanent laryngeal nerve paralysis. We registered no persistent or recurrent disease (mean follow-up 12.8 months, range 1-28).

CONCLUSIONS

Video-assisted parathyroidectomy is feasible, and its results are similar to those of traditional procedure, while it seems superior as regards postoperative course and aesthetic results. It also allows different strategical decisions even during operation (i.e. bilateral exploration or thyroid lobectomy) by the same approach.

Investigations into the sterility of manually assembled extracorporeal circuits with vented reservoirs

This study was designed to investigate the ability of an extracorporeal circuit (ECC) with a vented hard shell reservoir to remain sterile for a period of 72 h under dry conditions. The study was conducted in three phases. In Phase One: Two previously published methods for detecting contamination of the ECC were compared. A group of positive controls was collected by contaminating identical circuits with a known level of Enterobacter cloacae (ATTC: 13047) before initiating a regimen of "sample-dilute-sample" culturing. Negative controls for this phase were conducted by randomly sampling 1 L per manufacturer's lot of lactated ringers with each detection method. Culture results suggest that large volume filtration, but not small aliquot sampling, is sensitive to extremely low levels of contamination. No growth was detected in any negative control samples. In Phase Two: 19 ECC consisting of a membrane oxygenator, vented hardshell reservoir, arterial filter, and PVC tubing were removed from their sterile packages, assembled, and left unprotected in the moderate traffic environment of a research laboratory. The circuits were then primed with Lactated Ringer's solution. The prime solution was sampled for aerobic contamination by large volume filtration. None of the 19 samples detected contamination. In Phase Three: 43 ECC identical to the Phase Two circuits were assembled and left unprotected in the substerile pump room. The circuits were then primed, circulated, and cultured as in Phase Two. One of the 43 samples was discarded because of a recognized break in aseptic technique during sample collection. None of the remaining samples detected contamination. Mathematical calculations of binomial probabilities suggest that the chance of an open ECC developing a detectable level of contamination within 72 h of its dry assembly is insignificant.

Multicenter study on hepatitis C virus infection in patients with dilated cardiomyopathy. North Italy Transplant Program (NITP)

Preliminary epidemiological and histological studies from Japan suggested that hepatitis C virus (HCV) infection has a role in the development of dilated cardiomyopathy (DCM). This multicenter study was conducted to verify this hypothesis on a large cohort of Italian patients with end-stage heart failure. Antibodies to HCV were determined in the 752 consecutive patients (608 males and 144 females; age, 53 +/- 13 years) who entered the waiting list for cardiac transplantation from 1995 to 1997 at the six cardiac surgery centers participating in the North Italy Transplant program. Three hundred and nine patients (41%) had dilated, 9 (1%) restrictive, and 4 (0.5%) hypertrophic cardiomyopathy; 284 patients (38%) had ischemic, 65 (9%) valvular, and 22 (3%) congenital heart disease; 5 patients (0.5%) had primary pulmonary hypertension; 54 patients (7%) had other or nonspecified heart disease. Overall, 41 of 752 patients (5.4%) resulted anti-HCV-reactive. Serological evidence of HCV infection was found in 12 of 309 patients with DCM (3.9%; 95% CI, 1.7-6.0), and in 29 of 443 without DCM (6.5%; 95% CI, 4.2-8.8), without statistical difference (difference of prevalence rate: 2.6%; 95% CI, -4.9 to 5.8). In conclusion, HCV does not seem to have a primary role in the pathogenesis of DCM. However, since our findings are in disagreement with those obtained in smaller series of patients of other ethnicity, large studies from different countries should be conducted.

No evidence for mutations in the calcium-sensing receptor gene in sporadic parathyroid adenomas

Inactivating mutations of the calcium-sensing receptor gene (CaR) might explain abnormalities in the regulation of both parathyroid cell proliferation and parathyroid hormone secretion. In a previous study, using RNAse A protection assay, no mutations were identified in a series of parathyroid specimens from patients with primary and secondary hyperparathyroidism, but the analysis was incomplete, since part of exon 6 could not be analyzed. In the present study, we examined the presence of mutations in the CaR gene in 20 parathyroid adenomas using direct sequencing. The entire coding region of the CaR gene was successfully amplified by polymerase chain reaction and directly sequenced. This analysis did not identify CaR gene mutations in any tumors studied. A polymorphism that encoded a single amino acid change (Ala826Thr) was identified in 4 parathyroid adenomas and in 8 of 50 normal unrelated subjects. Loss of heterozygosity studies were also performed on adenomas using markers for the locus of the CaR gene on chromosome 3q. No allelic loss was demonstrated. In conclusion, our results extend previous observation and suggest that clonal somatic mutations of the CaR gene and allelic loss at the CaR locus on chromosome 3q do not play a major role in the pathogenesis of sporadic parathyroid tumors.

A new mutation of the MEN1 gene in an italian kindred with multiple endocrine neoplasia type 1

OBJECTIVE

To report a new mutation of the multiple endocrine neoplasia type 1 (MEN1) gene in an Italian kindred.

DESIGN

The study included the female proband, aged 50 years, affected by primary hyperparathyroidism, insulinoma and prolactinoma, and ten relatives. Blood samples were obtained for biochemical and genetic analyses. Clinical screening tests included serum glucose, ionized calcium, intact parathyroid hormone, GH, insulin and prolactin. The coding sequence, including nine coding exons and 16 splice sites, was amplified by PCR and directly sequenced.

RESULTS

Two additional cases of primary hyperparathyroidism were identified among the paternal family members. The sequence analysis showed a heterozygous T to C transition at codon 444 in exon 9, resulting in a leucine to proline substitution (L444P) in the patient and in the two paternal family members with primary hyperparathyroidism. The L444P amino acid change was absent in 50 normal subjects. The mutation determined the loss of a BlnI restriction site of the wild-type sequence and the creation of a new restriction EcoRII site. The patient, but not her paternal affected relatives, also had a common heterozygous polymorphism (D418D) in exon 9.

CONCLUSIONS

A new MEN1 mutation (L444P) in exon 9 has been identified; this substitution caused the loss of a BlnI restriction site and the creation of a new EcoRII site.

A multicenter prospective study on the risk of acquiring liver disease in anti-hepatitis C virus negative patients affected from homozygous beta-thalassemia

Although the risk of transfusion-transmitted hepatitis has been recently reduced, transfusion-dependent beta-thalassemia patients may still develop liver disease due to viral infection or iron overload. We assessed the frequency and causes of liver dysfunction in a cohort of anti-hepatitis C virus (HCV) negative thalassemics. Of 1,481 thalassemics enrolled in 31 centers, 219 (14.8%) tested anti-HCV- by second-generation assays; 181 completed a 3-year follow-up program consisting of alanine-aminotransferase (ALT) measurement at each transfusion and anti-HCV determination by third-generation enzyme-immunoassay (EIA-3) at the end of study. Serum ferritin levels were determined at baseline and at the end of follow-up. Ten patients were anti-HCV+ by EIA-3 at the end of follow-up. Of them, seven were already positive in 1992 to 1993 when the initial sera were retested by EIA-3, one tested indeterminate by confirmatory assay, and two had true seroconversion (incidence, 4. 27/1,000 person years; risk of infection, 1/7,100 blood units, 95% confidence interval [CI], 1 in 2,000-1 in 71,000 units). At baseline, 67 of 174 thalassemics had abnormal ALT. Of those with normal ALT, seven subsequently developed at least one episode of moderate ALT increase (incidence, 24.6/1,000 person-years). All of the 20 patients with ferritin values >/=3,000 ng/mL had clinically relevant ALT abnormalities, as compared with 53 of 151 with <3,000 ng/mL (P < .005). Hepatic dysfunction is still frequent in thalassemics. Although it is mainly attributable to siderosis and primary HCV infection, the role of undiscovered transmissible agents cannot be excluded.

Aerosolized surfactant improves pulmonary function in endotoxin-induced lung injury

Surfactant dysfunction is a primary pathophysiologic component in patients with adult respiratory distress syndrome (ARDS). In this study we tested the efficacy of aerosolized surfactant (Sf ) replacement in a severe lung injury model of endotoxin-induced ARDS. Twenty-one certified healthy pigs were anesthetized, surgically prepared for measurement of hemodynamic and lung function, then randomized into one of four groups: (1) control (n = 5), surgical instrumentation only; (2) lipopolysaccharide (LPS) (n = 6), infused with Escherichia coli LPS (100 microgram/kg) without positive end- expiratory pressure (PEEP) and ventilated with a nonhumidified gas mixture of 50% N2O and 50% O2; (3) LPS + PEEP (n = 4), infused with LPS, placed on PEEP (7.5 cm H2O), and ventilated with a humidified gas mixture; and (4) LPS + PEEP + Sf (n = 6), infused with LPS, placed on PEEP, and ventilated with aerosolized Sf (Infasurf, ONY, Inc.). All animals were studied for 6 h. Arterial PO2 significantly decreased in both the LPS and LPS + PEEP groups (LPS + PEEP = 74 +/- 19 mm Hg; LPS = 74 +/- 19 mm Hg, p < 0.05) while venous admixture (Q S/Q T) increased in these groups (LPS + PEEP = 43.3 +/- 3.9%; LPS = 47.7 +/- 11%, p < 0.05) as compared with the control group. PEEP + Sf reduced the fall in PO2 (142 +/- 20 mm Hg) and rise in Q S/Q T (15.1 +/- 3.6%) caused by LPS. Delayed induction of PEEP (2 h following LPS) did not significantly improve any parameter over the LPS group without PEEP in this ARDS model. LPS without PEEP (3.4 +/- 0.2 cells/6,400 micrometer2) caused a marked increase in the total number of sequestered leukocytes in the pulmonary parenchyma as compared with the control group (1.3 +/- 0.1 cells/6,400 micrometer2). LPS + PEEP + Sf (2.3 +/- 0.2 cells/6,400 micrometer2) significantly decreased while LPS + PEEP significantly increased (4.0 +/- 0.2 cells/6,400 micrometer2) the total number of sequestered leukocytes as compared with the LPS without PEEP group. In summary, aerosolized surfactant replacement decreased leukocyte sequestration and improved oxygenation in our porcine model of endotoxin-induced lung injury.

Exogenous surfactant and positive end-expiratory pressure in the treatment of endotoxin-induced lung injury

OBJECTIVE

To evaluate the efficacy of treating endotoxin-induced lung injury with single dose exogenous surfactant and positive end-expiratory pressure (PEEP).

DESIGN

Prospective trial.

SETTING

Laboratory at a university medical center.

SUBJECTS

Nineteen certified healthy pigs, weighing 15 to 20 kg.

INTERVENTIONS

Pigs were anesthetized and surgically prepared for hemodynamic and lung function measurements. Animals were randomized into four groups: a) Control pigs (n = 4) received an intravenous infusion of saline without Escherichia colilipopolysaccharide (LPS); b) the LPS group (n = 5) received an intravenous infusion of saline containing LPS (100 microg/kg); c) the PEEP plus saline group (n = 5) received an intravenous infusion of saline containing LPS. Two hours after LPS infusion, saline was instilled into the lung as a control for surfactant instillation, and the animals were placed on 7.5 cm H2O of PEEP; d) the PEEP plus surfactant group (n = 5) received an intravenous infusion of saline containing LPS. Two hours following LPS infusion, surfactant (50 mg/kg) was instilled into the lung and the animals were placed on 7.5 cm H2O of PEEP. PEEP was applied first and surfactant or saline was instilled into the lung while maintaining positive pressure ventilation. All groups were studied for 6 hrs after the start of LPS injection. At necropsy, bronchoalveolar lavage was performed and the right middle lung lobe was fixed for histologic analysis.

MEASUREMENTS AND MAIN RESULTS

Compared with LPS without treatment, PEEP plus surfactant significantly increased PaO2 (PEEP plus surfactant = 156.6 +/- 18.6 [SEM] torr [20.8 +/- 2.5 kPa]; LPS = 79.2 +/- 21.9 torr [10.5 +/- 2.9 kPa]; p<.05), and decreased venous admixture (PEEP plus surfactant = 12.5 +/- 2.0%; LPS = 46.9 +/- 14.2%; p< .05) 5 hrs after LPS infusion. These changes were not significant 6 hrs after LPS infusion. PEEP plus surfactant did not alter ventilatory efficiency index (VEI = 3800/[peak airway pressure - PEEP] x respiratory rate x PacO2), or static compliance as compared with LPS without treatment at any time point. Cytologic analysis of bronchoalveolar lavage fluid showed that surfactant treatment significantly increased the percentage of alveolar neutrophils as compared with LPS without treatment (PEEP plus surfactant = 39.1 +/- 5.5%; LPS = 17.4 +/- 6.6%; p< .05). Histologic analysis showed that LPS caused edema accumulation around the airways and pulmonary vessels, and a significant increase in the number of sequestered leukocytes (LPS group = 3.4 +/- 0.2 cells/6400 micro2; control group = 1.3 +/- 0.1 cells/6400 micro2; p < .05). PEEP plus saline and PEEP plus surfactant significantly increased the total number of sequestered leukocytes in the pulmonary parenchyma (PEEP plus surfactant = 8.2 +/- 0.7 cells/6400 micro2; PEEP plus saline = 3.9 +/- 0.2 cells/6400 micro2; p <.05) compared with the control and LPS groups.

CONCLUSIONS

We conclude that PEEP plus surfactant treatment of endotoxin-induced lung injury transiently improves oxygenation, but is unable to maintain this salutary effect indefinitely. Thus, repeat bolus dosing of surfactant or bolus treatment followed by continuous aerosol delivery may be necessary for a continuous beneficial effect.

Preoperative localization of suspicious parathyroid adenomas by assay of parathyroid hormone in needle aspirates

OBJECTIVE

To determine the usefulness of parathyroid hormone (PTH) measurement in needle aspirates of a suspicious neck mass to confirm its parathyroid nature in patients with primary hyperparathyroidism.

METHODS

Thirty-three patients with surgically proved primary hyperparathyroidism were submitted to neck ultrasound (US), parathyroid scintigraphy, and assay of PTH in the aspirate (PTHa) of the suspicious cervical mass.

RESULTS

Based on the results of neck US and parathyroid scintigraphy, patients were divided into two groups. Group 1: 16 patients (seven with nodular goiter) with concordant positive US and scintigraphic results. In all but one patient, PTHa was detectable and often markedly elevated (> 1000 pg in 12 patients, between 292 pg and 803 pg in three patients and 53 pg in one patient). The patient with undetectable PTHa had a small lower left parathyroid adenoma (8x8x10 mm). Group 2: 17 patients (12 with nodular goiter) with discordant US and scintigraphic results. PTHa established the parathyroid nature of the mass in 13 cases (> 1000 pg in 8 patients, between 501 pg and 953 pg in three patients and 90 and 79 pg in two patients): 11 of these had a suspected lesion by US examination but the scintigraphy results were negative; two had a mass that gave positive scintigraphy results but was of uncertain origin according to US: in both cases an intrathyroidal parathyroid adenoma was found. PTHa was undetectable in four cases (three with nodular goiter): all of these had equivocal US results, and three had positive scans and one a negative scan.

CONCLUSIONS

Assay of PTHa is a simple method and should be useful for confirming the parathyroid nature of a cervical mass in patients with discordant or non-diagnostic US and scintigraphic results.

Minimally invasive, video-assisted parathyroid surgery for primary hyperparathyroidism

A new video-assisted surgical procedure for treatment of primary hyperparathyroidism combined with intraoperative quick PTH measurement was developed. This procedure was successfully used in 6 patients with a single parathyroid adenoma preoperatively localized by neck ultrasound examination.

Defibrillator twiddler's syndrome: a rare cause of implantable cardioverter-defibrillator failure

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Effect of morphine and naloxone on motor response of the human esophagus to swallowing and distension

The effect of morphine on esophageal motility has been little explored. In eight healthy volunteers, we studied the effect of intravenous morphine (100 micrograms/kg) followed 60 min later by intravenous naloxone (80 micrograms/kg) and of intravenous naloxone alone (80 micrograms/kg) on the esophageal motor response to swallowing and 30-s intraluminal distensions(4, 6, 8, and 10 ml) during two separate experiments. Morphine increased (P < 0.01) the velocity but did not alter the amplitude or duration of primary peristalsis, and it decreased the duration and magnitude of swallow-induced lower esophageal sphincter (LES) relaxation (P < 0.01). It also markedly increased contractile activity below the balloon at high distending volumes (P < 0.05) and decreased the magnitude of distension-induced LES relaxation (P < 0.05) but did not affect contractile activity above the balloon. All effects were reversed by naloxone. The latter alone did not influence the esophageal response to swallowing or distension. The conclusions are that 1) morphine exerts effects on the response of the human esophagus to swallowing and intraluminal distension that are consistent with an action at the level of the inhibitory neural pathways, 2) these effects occur through opioid receptors, and 3) endogenous opioids do not seem to control esophageal motility, at least through mu-receptors.

Quantification of the oesophageal peristaltic reflex in man

The peristaltic reflex represents the basis of peristalsis and has two components, ascending contraction above and descending relaxation below the site of distension. Studies of the two components of the reflex in the human oesophagus performed by concurrent monitoring of oesophageal body and lower oesophageal sphincter (LOS) motility are lacking. We investigated the peristaltic reflex in eight healthy volunteers (aged 19-25 years; five male, three female) by two series of eight graded (3-10 mL) balloon distensions performed 11 cm above the LOS, monitoring motor activity in the oesophageal body both above and below the balloon and in the LOS (sleeve sensor). During balloon distension both ascending contraction, as assessed by contractile activity above the balloon, and descending relaxation, as assessed by LOS relaxation, increased linearly with increasing inflation volumes (r = 0.6 and r = 0.8, respectively, both P < 0.0001). The threshold for descending relaxation was lower than that for ascending contraction. The contractile response of the body below the balloon was always lower than above the balloon and occurred with a higher (P < 0.05) frequency at 6 and 7 mL compared to 3, 4 and 10 mL. After balloon deflation an oesophageal contraction, usually accompanied by an LOS contraction, occurred with increasing frequency as the balloon volume increased. Our experimental model allows detailed assessment of the two components of the peristaltic reflex in the human oesophagus in vivo and should prove useful in future studies on the physiology and pathophysiology of this reflex.