Energy-temperature uncertainty relation in quantum thermodynamics.

It is known that temperature estimates of macroscopic systems in equilibrium are most precise when their energy fluctuations are large. However, for nanoscale systems deviations from standard thermodynamics arise due to their interactions with the environment. Here we include such interactions and, using quantum estimation theory, derive a generalised thermodynamic uncertainty relation valid for classical and quantum systems at all coupling strengths. We show that the non-commutativity between the system's state and its effective energy operator gives rise to quantum fluctuations that increase the temperature uncertainty. Surprisingly, these additional fluctuations are described by the average Wigner-Yanase-Dyson skew information. We demonstrate that the temperature's signal-to-noise ratio is constrained by the heat capacity plus a dissipative term arising from the non-negligible interactions. These findings shed light on the interplay between classical and non-classical fluctuations in quantum thermodynamics and will inform the design of optimal nanoscale thermometers.

Assessment of myofascial medialization following posterior component separation via transversus abdominis muscle release in a cadaveric model.

PURPOSE: Posterior component separation (PCS) via the transversus abdominis release (TAR) procedure continues to gain popularity. However, neither the physiologic basis nor the extent of myofascial medialization after TAR is established. We aimed to assess both anterior and posterior rectus fascia (AF and PF) medialization following each step of the TAR procedure. METHODS: Ten fresh cadavers underwent PCS via TAR. Steps included midline laparotomy (MLL), retrorectus dissection (RRD), incision of the posterior rectus sheath (IPL), transversus abdominis muscle division (TAD), and retromuscular dissection (RMD). Medial advancement of AF and PF was measured following application of 2.5, 5.0 lb, and maximal tension to the fascial edge. Values are represented as mean advancement past midline in centimeters. RESULTS: MLL allowed advancement of 2.5, 3.7, and 4.9 cm. RRD provided advancement of 4.1, 5.9, and 7.6 cm for AF and 4.4, 6.2, and 7.5 cm for PF. IPL provided advancement of 4.2, 6.1, and 8.0 cm for AF and 4.6, 6.6, and 8.3 cm for PF. TAD provided advancement of 4.5, 6.6, and 8.6 cm for AF and 5.3, 7.5, and 9.5 cm for PF. RMD provided advancement of 5.5, 7.9, and 9.9 cm for AF and 6.9, 9.6, and 11.2 cm for PF. Overall, the complete TAR procedure provided AF advancement of 102% and PF advancement of 129%, over baseline. CONCLUSIONS: The TAR procedure provides for substantial medial advancement of both anterior and posterior myofascial components of the abdominal wall. Retromuscular dissection deep to the divided transversus abdominis muscle appears to be the key step of the procedure, allowing for effective reconstruction of very wide (≈ 20 cm) defects.

Entropy production and time asymmetry in the presence of strong interactions.

It is known that the equilibrium properties of open classical systems that are strongly coupled to a heat bath are described by a set of thermodynamic potentials related to the system's Hamiltonian of mean force. By adapting this framework to a more general class of nonequilibrium states, we show that the equilibrium properties of the bath can be well defined, even when the system is arbitrarily far from equilibrium and correlated with the bath. These states, which retain a notion of temperature, take the form of conditional equilibrium distributions. For out-of-equilibrium processes we show that the average entropy production quantifies the extent to which the system and bath state is driven away from the conditional equilibrium distribution. In addition, we show that the stochastic entropy production satisfies a generalized Crooks relation and can be used to quantify time asymmetry of correlated nonequilibrium processes. These results naturally extend the familiar properties of entropy production in weakly coupled systems to the strong coupling regime. Experimental measurements of the entropy production at strong coupling could be pursued using optomechanics or trapped-ion systems, which allow strong coupling to be engineered.

Previous cesarean section. A contraindication to vaginal hysterectomy?

OBJECTIVE: To compare surgical outcomes of vaginal hysterectomy between women who have had one or more cesarean deliveries and those who have not. STUDY DESIGN: A retrospective, chart review study was performed on women undergoing vaginal hysterectomy during a four-year period. Of 275 women who met the study criteria, 104 had a history of previous cesarean deliveries, and 171 did not. The groups were compared for indications for surgery, operative time, length of hospitalization and surgical complications. RESULTS: Previous cesarean delivery did not affect hemoglobin loss, hospital stay or operative time among women undergoing vaginal hysterectomy. The complication rate (either operative or postoperative) was 12.3% among women without a history of cesarean section, 6.8% among those with one, 3.7% among those with two and 11.1% among those with three or more (chi 2 = 2.8, P = .4). The odds for surgical complications were not significantly different between women with one or more prior cesarean deliveries as compared to those without after adjustment for possible confounders. CONCLUSION: Surgical complications with vaginal hysterectomy do not appear to be higher among women with a prior cesarean section as compared to those without a history of such operation.

Timing of subsequent pregnancy following treatment of molar pregnancy.

OBJECTIVE: To assess the practice habits and recommendations of members of American Society of Gynecologic Oncologists (ASGO) dealing with follow-up management of molar pregnancy. MATERIALS AND METHODS: A questionnaire was mailed to ASGO members requesting their recommended waiting period for subsequent pregnancy following treatment of molar pregnancy. Year of Fellowship completion was determined for each respondent. RESULTS: Only 36.8% still recommended the traditionally accepted 12-month waiting period, and 31.3% recommended 6 months. The trend was toward shorter waiting periods among younger, more recently trained oncologists, although differences were not statistically significant. CONCLUSION: It appears time to review the recommendation of a 12-month waiting period. A reduction of at least down to 6 months may be appropriate, but needs further investigation.

Identification of imprinted loci by methylation-sensitive representational difference analysis: application to mouse distal chromosome 2.

Imprinted genes are distinguished by different patterns of methylation on their parental alleles, a property by which imprinted loci could be identified systematically. Here, representational difference analysis (RDA) is used to clone HpaII fragments with methylation differences on the maternal and paternal copies of distal chromosome (Chr) 2 in the mouse. Uniparental inheritance for this region causes imprinting phenotypes whose molecular basis is only partially understood. RDA led to the recovery of multiple differentially methylated HpaII fragments at two major sites of imprinted methylation: paternal-specific methylation at the Nesp locus and maternal-specific methylation at the Gnasxl locus. Nesp and Gnasxl represent oppositely imprinted promoters of the Gnas gene, which encodes the G-protein subunit, Gsalpha. The organization of the Nesp-Gnasxl-Gnas region was determined: Nesp and Gnasxl were found to be 15 kb apart, and Gnasxl was found to be 30 kb upstream of Gnas. Sites of imprinted methylation were also detected at the loci for neuronatin on Chr 2 and for M-cadherin on Chr 8. RDA was highly effective at identifying imprinted methylation, and its potential applications to imprinting studies are discussed.

A cluster of oppositely imprinted transcripts at the Gnas locus in the distal imprinting region of mouse chromosome 2.

Imprinted genes tend to occur in clusters. We have identified a cluster in distal mouse chromosome (Chr) 2, known from early genetic studies to contain both maternally and paternally imprinted, but unspecified, genes. Subsequently, one was identified as Gnas, which encodes a G protein alpha subunit, and there is clinical and biochemical evidence that the human homologue GNAS1, mutated in patients with Albright hereditary osteodystrophy, is also imprinted. We have used representational difference analysis, based on parent-of-origin methylation differences, to isolate candidate imprinted genes in distal Chr 2 and found two oppositely imprinted genes, Gnasxl and Nesp. Gnasxl determines a variant G protein alpha subunit associated with the trans-Golgi network and Nesp encodes a secreted protein of neuroendocrine tissues. Gnasxl is maternally methylated in genomic DNA and encodes a paternal-specific transcript, whereas Nesp is paternally methylated with maternal-specific expression. Their reciprocal imprinting may offer insight into the distal Chr 2 imprinting phenotypes. Remarkably, Gnasxl, Nesp, and Gnas are all part of the same transcription unit; transcripts for Gnasxl and Nesp are alternatively spliced onto exon 2 of Gnas. This demonstrates an imprinting mechanism in which two oppositely imprinted genes share the same downstream exons.

Paclitaxel as the initial treatment of multiple myeloma: an Eastern Cooperative Oncology Group Study (E1A93).

The authors assess the activity and toxicity of paclitaxel in previously untreated patients with multiple myeloma. Eighteen patients with previously untreated multiple myeloma were enrolled. Paclitaxel was given in a dose of 250 mg/m2 by a continuous intravenous infusion for 24 hours every 21 days for four cycles. All patients received granulocyte colony stimulating factor in a dose of 5 microg/kg each day until the absolute neutrophil count was 10,000/mm3. All patients were evaluated after four cycles. Four (29%) objective responses were observed in the 14 eligible patients. No complete responses occurred. Three lethal toxicities were observed, two were the result of neutropenic sepsis. Sixty-one percent of patients experienced some type of severe nonhematologic toxicity. Patients who received four cycles of paclitaxel were given further treatment at the discretion of the investigator. The median survival of all eligible patients was 2.8 years, which is comparable with the median survival with melphalan and prednisone of 2.3 years or vincristine, carmustine, melphalan, cylophosphamide, and prednisone of 2.4 years. Paclitaxel in the dosage used in this study has prohibitive toxicity. The four (29%) responses in 14 evaluable untreated patients indicates that paclitaxel is active in the treatment of multiple myeloma. No complete remissions were recorded. Further studies using paclitaxel in a smaller dose, in combination with other agents, or using one of the paclitaxel analogs may be useful in the treatment of multiple myeloma.

Problem focused knowledge navigation: implementing the problem focused medical record and the O-HEAP note.

The current organization of most Computerized Medical Records (CMR) is based on the Problem Oriented Medical Record (POMR) and the SOAP (Subjective, Objective, Assessment and Plan) note. The organizational structure of the POMR and especially the SOAP note, does not allow for optimal use of computer capabilities in the follow up note. Since follow up visits are the most common office visit by far, this is a major flaw in the CMR. The authors propose a Problem Focused Medical Record and the OHEAP (Orientation, History, Exam, Assessment and Plan) note to resolve this problem. OHEAP starts with a powerful orientation structure that brings forward the timeline, last Assessment and Plan, and Plan Results for each problem along with the patient's historical tables as the starting point of every follow up visit. The Assessment and Plan portion brings problem specific differential diagnoses and their workups along with other relevant tables such as expert systems, treatments, instructions, medical literature or pathways. This leads to Problem Focused Knowledge Navigation that brings powerful efficiencies to the CMR. By recognizing the true workflow in the longitudinal diagnosis and management of any medical problem, the efficiency of the CMR is maximized. OHEAP allows for optimal use of both personal and external data elements in the medical record. Its powerful orientation attributes minimize the time spent in analyzing the current status of the problem while its connections to problem specific databases help resolve the problem.

The treatment of older adult patients with acute myeloid leukemia by triple infusion chemotherapy.

Adult patients (> or = 56 years old) with acute myeloid leukemia (AML) received induction therapy consisting of daunorubicin (60 mg/m2), etoposide (80 mg/m2), and cytarabine (200 mg/m2) daily for 5 days by continuous i.v. infusion (120 hours). The initial protocol was modified so that patients who were not hypoplastic after the first cycle of chemotherapy received a second cycle of treatment, utilizing 30 mg/m2 of daunorubicin/24 hours for 5 days plus etoposide and cytarabine as used in the first cycle. Two courses of consolidation with etoposide and cytarabine at the same dose and schedule were given. Patients were then maintained on cytarabine monthly. Twelve of 29 previously untreated patients (41%) achieved complete remission (CR). Excluding patients with secondary AML, 48% of all patients (11/23) achieved CR, including 56% > or = 70 years old. The median duration of CR was 41 weeks and median survival of CR patients was 54 weeks. Six of 13 patients (46%) with relapsed AML achieved CR. Toxicity in these older adult patients has been mild. Two patients (8%) had severe mucositis and one had severe (bloody) diarrhea. Most patients developed a mild transient asymptomatic rash. Triple infusion chemotherapy (TIC) may be as effective as other chemotherapy regimens for AML in older adults and has acceptable toxicity.

POEMS syndrome presenting with cardiomegaly and cardiomyopathy.

A rare association of multisystemic manifestations with plasma cell dyscrasia has been termed POEMS syndrome, which includes polyneuropathy, organomegaly, endocrinopathy. M-protein, and skin changes. From literature reports, organomegaly consists of hepatosplenomegaly and/or lymphadenopathy. We here present a case of POEMS syndrome that had most of the typical features of POEMS, except that organomegaly only involved the heart. The patient's multiple clinical manifestations, including cardiomyopathy, improved with chemotherapy, which is characteristic of POEMS syndrome. However, cardiomegaly or cardiomyopathy have not previously been described with POEMS. The present case suggests that cardiomegaly and cardiomyopathy may be added to the organomegaly in POEMS.

Pneumobelt use among high quadriplegic population.

This study reviews pneumobelt use in an acute rehabilitation facility. All pneumobelt users between 1976 and 1986 were identified. Their age, sex, diagnosis, and time required to adjust to the pneumobelt were studied, as were patterns of use at discharge. Information was collected about use after discharge and about reported advantages and disadvantages. Twenty-three subjects were identified: 21 had spinal cord injuries (SCI), two had had poliomyelitis. The average pneumobelt fitting was three to six months after injury. Twelve SCI patients attained four or more hours of continuous, generally all-day use; another patient achieved this after discharge. Of the remaining eight SCI subjects, all achieved a minimum of two hours of continuous use. The two poliomyelitis patients also achieved all-day use. The survey revealed a high level of satisfaction and continued pneumobelt use after discharge. Major reported advantages were cosmesis, improved speech, independence and mobility, comfort, safety, and health. The pneumobelt is recommended as a leading choice for interim or permanent ventilation of the high quadriplegic population without severe brainstem involvement.

Pediatric human immunodeficiency virus infection and its cutaneous manifestations.

Acquired immunodeficiency syndrome was first observed in children in 1982. Human immunodeficiency virus (HIV) is now known to be the etiologic agent of this disease complex. Children acquire the viral infection in utero or perinatally, or by receiving contaminated blood products. The cutaneous manifestations include persistent oral thrush, herpes simplex, herpes zoster, molluscum contagiosum, and a variety of fungal and bacterial skin infections. Vasculitis, unusual drug eruptions, and cutaneous manifestations of nutritional deficiencies are also seen.

Non-Hodgkin's lymphoma, HTLV-III/LAV, and HTLV-III/LAV antibody in the wife of a man with transfusion-acquired AIDS.

Non-Hodgkin's lymphoma of the small intestine developed in a 66-year-old woman who was the wife of a man with transfusion-related acquired immune deficiency syndrome (AIDS). Antibody to the human T lymphotrophic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV) was present in her serum, and the virus was isolated from her peripheral lymphocytes. The possibility that the non-Hodgkin's lymphoma in this patient was a manifestation of HTLV-III/LAV infection is discussed. This is believed to be the first reported case of lymphoma occurring in a patient with documented HTLV-III/LAV infection outside the male homosexual risk group.

Neurologic involvement in glucagonoma syndrome: response to combination chemotherapy with 5-fluorouracil and streptozotocin.

A 34-year-old man presented with classic glucagonoma syndrome manifested by weight loss, dermatitis, stomatitis, anemia, and mild diabetes mellitus. The diagnosis of glucagonoma was made by light and electron microscopic demonstration of a metastatic alpha cell carcinoma in a liver biopsy specimen. Plasma glucagon concentration was abnormally high. The patient also had symptoms and signs of involvement of the central nervous system. Radionuclide and CAT scans of the brain, negative CSF cytology and myelography excluded the possibility of metastases or other space-occupying lesions. Glucagon was demonstrated in the CSF. We postulate that the neurologic symptoms were due to direct or indirect effect of this hormone on the brain. Following therapy with streptozotocin and 5-fluorouracil, the patient had a subjective and objective clinical and hormonal remission of his disease including amelioration of his neurological impairment.

World PCBs map: storage and effects in man and his biologic environment in the 1970s.

PCB residues are found in biota all over the world. A biologic magnification of PCBs has been demonstrated in the food chain: plankton-fish-fish eating birds. A world map of the PCBs residues in biota and some of their biologic effects are given in this study. The biologic effects of PCBs are varied and may generally be explained by the induction or inhibition of the activity of a large number of enzymes, which upsets quantitatively, normal biochemical processes. Harm to reproduction, growth, development, defense systems, tissues, and organs appeared in susceptible organisms as a result of such changes or as a chain reaction to heterostases. The adverse health effects, observed in persons occupationally exposed and in those accidentally poisoned, point to the risk for the general population of an ever-increasing environmental pollution by PCBs. There is need for an integrated approach, consisting of epidemiologic studies on high risk groups in the general population and in persons occupationally exposed, as well as periodic assessment of PCB residues in man, his food, and feed supplies.