A genomic clone encoding the alpha chain of the OKM1, LFA-1, and platelet glycoprotein IIb-IIIa molecules.

LFA-1, an antigen involved in cytolytic T lymphocyte-mediated killing, and Mac-1, the receptor for complement component C3bi, constitute a family of structurally and functionally related cell surface glycoproteins involved in cellular interactions. In both mouse and man, Mac-1 (OKM1) and LFA-1 share a common 95-kDa beta subunit but are distinguished by their alpha chains, which have different cellular distributions, apparent molecular masses (165 and 177 kDa, respectively), and peptide maps. We report the isolation of a genomic clone from a human genomic library that on transfection into mouse fibroblasts produced a molecule(s) reactive with monoclonal antibodies to OKM1, to LFA-1, and to platelet glycoprotein IIb-IIIa. This gene was cloned by several cycles of transfection of L cells with a human genomic library cloned in lambda phage Charon 4A and subsequent "rescue" of the lambda phage. Transfection with the purified recombinant lambda DNA yielded a transfectant that expressed the three human alpha chains of OKM1, LFA-1, and glycoprotein IIb-IIIa, presumably in association with the murine beta chain.     

Comparison of benign and malignant insulinoma

BackgroundHow malignant insulinomas present relative to benign insulinomas is unknown.MethodsA single-institution retrospective study identified patients with insulinoma. Malignancy was defined by distant metastases, positive lymph node(s), T stage of 4, direct invasion into surrounding peripancreatic tissue, or presence of lymphovascular invasion. Wilcoxon Rank Sum tests and Kaplan-Meier analysis were used.ResultsA total of 311 patients were identified: 51 malignant and 260 benign. Patients with malignant insulinoma presented with higher levels of insulin, proinsulin, and c-peptide. Malignant lesions were larger: 4.2 ± 3.2 vs 1.8 ± 0.8 cm in benign lesions, p < 0.01. Overall survival at 5 years was 66.8% vs 95.4% for malignant and benign insulinoma respectively, p < 0.01.ConclusionsLarger size of insulinoma and increased serum β-cell polypeptide concentrations were associated with malignancy. Malignant insulinoma has poorer survival. Further work-up to rule out malignancy may be indicated for larger pancreatic lesions and for patients with higher pre-operative insulin and pro-insulin.     

Is same-day discharge associated with increased 30-day postoperative complications and readmissions in patients undergoing laparoscopic adrenalectomy?

BackgroundAdvances in minimally invasive surgery and perioperative care have decreased substantially the duration of time that patients spend recovering in hospital, with many laparoscopic procedures now being performed on an ambulatory basis. There are limited studies, however, on same-day discharge after laparoscopic adrenalectomy. The objectives of this study were to investigate the outcomes and trends of ambulatory laparoscopic adrenalectomy in a multicenter cohort of patients.MethodsAdult patients who underwent elective laparoscopic adrenalectomy between 2005 and 2016 were identified in the database of the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP). Baseline demographics and 30-day outcomes were compared between patients who underwent ambulatory laparoscopic adrenalectomy and those who were discharged after an inpatient stay. Multivariable logistic regression and Cox proportional hazards modelling were used to investigate the association between same-day discharge and 30-day complications and unplanned readmissions.ResultsOf the 4,807 patients included in the study, 88 (1.8%) underwent ambulatory laparoscopic adrenalectomy and 4,719 (98.2%) were admitted after the adrenalectomy. The same-day discharge group contained fewer obese patients (37.2% vs 50%; P = .04), a lesser proportion of American Society of Anesthesiologists class III patients (45.5% vs 61%; P = .003), and more patients with primary aldosteronism (14.8% vs 6%; P = .002) compared with the inpatient group. After adjustment for confounders, same-day discharge was not associated with 30-day overall complications (OR 1.17, 95% CI 0.35–3.85; P = .80) or unplanned readmissions (HR 2.77, 95% CI 0.86–8.96; P = .09). The percentage of laparoscopic adrenalectomies performed on an ambulatory basis at hospitals participating in the ACS NSQIP remained low throughout the study period (0–3.1% per year) with no evidence of an increasing trend over time (P = .21).ConclusionAmbulatory laparoscopic adrenalectomy is a safe and feasible alternative to inpatient hospitalization in selected patients. Further study is needed to determine the cost savings, barriers to uptake, and optimal selection criteria for this approach.     

A three-zone model of soft-tissue damage by a CO2 laser

CO2 laser damage to soft tissue may be divided into three zones--an outer layer of carbonised material, a zone of vacuolation where cavities have been formed by the explosive conversion of water to steam and a coagulated zone which has been formed at temperatures below 100 degrees C. A model is proposed which predicts the maximum (i.e. dynamic equilibrium) depths of each of these layers. The maximum effective thickness of the vacuolated zone is shown to depend upon the absorption coefficient of the tissue for CO2 laser radiation, but not on the incident irradiance. The thickness of the carbonised zone is shown to decrease with increasing irradiance, and the depth of the sub-boiling coagulated zone also decreases with increasing irradiance, but depends to some extent on the penetration of laser radiation through the soft tissue. Redistribution of heat within these zones after extinction of the laser radiation is considered, as is the effect of pulsed laser radiation. The predictions of the model could be tested by suitable experiments.     

Process management: two control charts

It is not at all surprising that many persons avoid involvement in statistical process control. The statistical procedures developed in industry to monitor production processes are somewhat different from those employed in biostatistics and social science applications. Many find it difficult to adjust to these procedures and to apply statistical process control techniques to situations in health care settings. Not everyone involved in a QI process, however, needs to become versed in statistical process control techniques. At the Indiana University Medical Center several persons from different hospital departments have volunteered to form a cadre of internal statistical process control consultants. The group has come to be known by some as the statistical process control "think tank." No doubt a small group of individuals who are interested in statistics, quality control, and computers can be found in most hospitals. While it is necessary that the large majority of managers and supervisors in any health care organization are knowledgeable about process management and control charts at the concept level of understanding, it takes a relatively few to understand and use such control charts. As internal consultants, these few persons can provide technical assistance when such aid is needed.     

AIDS at the beginning of the second decade

Though at times tumultuous, the 6th International Conference on AIDS, hosted by in San Francisco, avoided the polarization of previous conferences and achieved a political success. Conference participants vehemently objected to the Immigration and Naturalization Service's policy of barring homosexuals and HIV carriers from entering the country, a practice that remained unchanged for the conference. Over 80 organizations boycotted the conference. Displeasure with US government policies was also evident when AIDS activists drowned out the speech by Secretary of Health and Human Services Louis Sullivan. While paper presentations by notable researchers appeared to be mostly a formality, since most of the information had already been published, useful exchanges did occur when scientists were, for a day, allowed to display abstracts on their latest research. But perhaps the most popular printed item on the conference was ACT UP's Research Agenda, a handout prepared by the AIDS activist group listing a series of drugs that should be tested and treatments that should be tried. Participants heard the disturbing news of the spread of the epidemic, of how 3.5 million Africans are infected, and of how Brazilian teenagers are at great risk of infection. Furthermore, participants discussed the high cost of AIDS care in the US (estimated at $85,000/patient) and the reluctance of insurance companies to cover AIDS-stricken patients. Aside from the exchange of information, the conference's real success came in the political arena, establishing itself as policymaker and champion of the affected.