Exposure of operating room personnel to nitrous oxide during paediatric anaesthesia

This study was undertaken to quantify the exposure of operating room staff to nitrous oxide during routine paediatric otolaryngeal surgery and to determine the influence of the method of induction of anaesthesia on this exposure. The nitrous oxide exposure of the anaesthetist, the surgeon and the circulating nurse were measured, using body-worn passive atmospheric samplers, during twelve routine paediatric otolaryngeal surgical lists. During six of the lists an inhalational technique, with nitrous oxide, oxygen and halothane, was used for the induction of anaesthesia. During the other six lists anaesthesia was induced using intravenous thiopentone. In all cases, anaesthesia was maintained using nitrous oxide, oxygen and halothane. Regardless of the induction technique used, the mean nitrous oxide exposures of the anaesthetist, the surgeon and the nurse all exceeded the maximum level of 25 ppm.hr-1 recommended by the United States National Institute for Occupational Safety and Health (NIOSH). The use of an intravenous technique for the induction of anaesthesia reduced the nitrous oxide exposure of the anaesthetist and the circulating nurse. This suggests that, although the use of an intravenous induction may reduce exposure to nitrous oxide, the NIOSH recommendations for maximum exposure of operating room personnel to nitrous oxide are currently unattainable in practice.

Loss of heterozygosity on chromosomes 1 and 11 in carcinoma of the pancreas

Little is known of the molecular-genetic changes in carcinoma of the pancreas (CaP). In order to investigate the allele loss, or loss of heterozygosity (LOH), in CaP, we studied 13 patients with exocrine CaP and two with endocrine CaP using restriction fragment length polymorphism analysis. Twenty probes assigned to chromosomes 1, 5, 7, 9, 11, 12, 13, 14, 16, 17 and 18 were used. The frequency of LOH, or fractional allele loss (FAL), was found in two endocrine tumours to be 0.333 and 0.455 respectively; and FAL in 13 oxocrine tumours ranged from 0 to 0.25. Allele loss was shown in both exocrine and endocrine tumours by the probes Lambda MS1 at 1p33-35, and pMS51 at 11q13. Probes for other chromosomes have as yet shown no consistent LOH. In conclusion, the study showed LOH on chromosomes 1 and 11 in both exocrine and endocrine CaP.

Identification and characterization of the bovine immunodeficiency-like virus tat gene

A cDNA clone of the bovine immunodeficiency-like virus (BIV) trans-activator gene (tat) was identified and characterized. The tat cDNA clone was generated by splicing, and on the basis of sequence analysis, the Tat protein was found to be encoded entirely by the first exon. It is 103 amino acids in size and shares sequence homology with the human immunodeficiency virus (HIV) Tat. The BIV tat clone can trans activate the BIV promoter effectively, as measured by the expression of the bacterial chloramphenicol acetyltransferase gene, when transfected into bovine cells. Besides activating the BIV promoter, the BIV Tat can also trans activate the HIV promoter effectively. It is possible that BIV Tat and HIV Tat employ similar mechanisms in trans activation of the viral long terminal repeat-directed gene expression.

Vicariance biogeography in the Pleistocene and speciation in North American wood warblers: a test of Mengel's model

It is widely believed that habitat fragmentation during the Pleistocene initiated speciation events in many songbird genera. One such vicariance model for avian speciation in the Pleistocene was developed by R. M. Mengel for North American birds. This model suggests that the first Pleistocene glacial advance reduced the area of an extensive, eastern North American deciduous forest, forcing adaptation by some species to boreal forest. This, in turn, facilitated the development of transcontinental range expansions during interglacials. Subsequent glacial advances repeatedly fragmented the ranges of these species into eastern and western populations; western isolates speciated to form the multispecies groups observed among various North American birds. We used mtDNA restriction site data to reconstruct the phylogeny of the black-throated green warbler complex-the group that Mengel considered the best fit to his model. Contrary to Mengel's model, the phylogeny indicates that not all western endemics were derived from an eastern ancestor. Instead, our results imply a mix, wherein some western endemics were budded off an eastern source, as Mengel posits, while others probably resulted from intermontane isolations in the west.

Differences in the tumor DNA analysis of a hepatocellular-carcinoma and a synchronous fibrolamellar variant

A 60 year old man had two tumours resected from his liver which were shown histologically to be a well differentiated hepatocellular carcinoma and the fibrolamellar variant. Both are considered clinically distinct and of different pathogenesis and have not been previously reported occurring synchronously. DNA analysis revealed allele loss on chromosome 12 in the hepatocellular carcinoma which was not found in the fibrolamellar variant. This finding may suggest that hepatocellular carcinoma and fibrolamellar variant may have different molecular-genetic mechanisms for the development, in addition to their clinico-pathological difference.

Signs and symptoms of temporomandibular joint dysfunction in a Saudi Arabian population

The signs and symptoms of temporomandibular joint dysfunction present in 219 Saudi Arabians attending a dental clinic for routine dental treatment are described. Joint sounds (36%) and muscle tenderness to palpation (34%) were common findings. Of the subjects examined, 31% reported suffering from frequent headaches. The study demonstrated a high incidence of signs and symptoms of temporomandibular joint dysfunction. Findings were similar to those of a previous study of an investigation in a bedouin community in Western Egypt (Abdel-Hakim, 1983).

Molecular characterization of two bacteriophages isolated from Desulfovibrio vulgaris NCIMB 8303 (Hildenborough)

A preliminary endonuclease restriction map of a bacteriophage isolated from Desulfovibrio vulgaris has been established. BamHI cleaved whole phage DNA into four fragments while HindIII cut the same DNA into seven fragments. Mapping studies succeeded in linking the four BamHI fragments into two DNA segments; however, no linkage between the two segments was detected. These data imply that two phages were induced from cultures of D. vulgaris and that the two segments represented the DNA from these phages. Support for this hypothesis came from size approximation of restriction enzyme fragments, electron micrographs, and density gradients.

Geriatric acute myocardial infarction: a challenge to recognition, prompt diagnosis, and appropriate care

The presentation of an AMI in the older person is often atypical, with a lower incidence of classic chest discomfort but increasing incidence of dyspnea, syncope, stroke, and acute confusion. Atypical presentation is especially common in those 85 years and older. The altered pattern of symptoms predisposes the elderly to a delayed or missed diagnosis. Delay in diagnosis may also occur when the ECG is nondiagnostic. In addition, enzyme elevations may be lower and fail to reflect the extent of myocardial damage. Thus, among the greatest challenges confronting critical care nurses is that of caring for elderly patients presenting with atypical AMI and concomitant polypathology. Nurses who are well informed about the normal age-related changes in the cardiovascular system contribute to more accurate and timely diagnosis and treatment of AMI in the elderly.

Minimally invasive gynaecological surgery

Most gynaecological operations can now be performed laparoscopically. The results for patients are a reduction in pain, less time spent in hospital and in convalescence and cost savings. For some procedures the risk of infection and adhesion formation is also reduced. This pelviscopic surgery requires extra training in special surgical skills to overcome the risks that include incomplete surgery resulting from poor access to a pelvic lesion or trauma to organs as a result of poor technique. Most patients with ectopic pregnancy, pelvic adhesions, endometriosis, ovarian cysts and fibromyomata can be treated by this advanced laparoscopic surgery. Hysteroscopic endometrial resection can replace hysterectomy for most patients with menorrhagia who have a normal size uterus.

Comparison of pain, motion, and edema after modified radical mastectomy vs. local excision with axillary dissection and radiation

Recent data suggest that prognosis is similar for women with primary breast cancer whether they receive modified radical mastectomy (MRM) or local excision and axillary dissection with radiation (XRT). The effects of either of these treatments on arm mobility, pain, or edema have not been compared. To assess the impact of MRM or XRT on mobility, pain, or edema, we evaluated patients treated in a prospective randomized trial designed to assess prognosis following MRM or XRT. All were provided a standardized physical therapy program including arm mobilization, shoulder strengthening, prevention and treatment of upper extremity edema, and education about arm function. Patients were evaluated for chest wall pain, arm motion, muscle strength, and edema as determined by circumferential measurements at the wrist, forearm, and arm. Evaluations were performed preoperatively and at yearly anniversaries of their surgery. Women receiving XRT had more chest wall tenderness at 1 and 2 years after surgery than those receiving MRM (p2 less than 0.0001 and p2 = 0.0007 respectively). Those receiving MRM were slower to reach their preoperative range of motion (ROM) (p2 = 0.043). Incidence of muscle weakness was similar in both groups. The few patients with local recurrence of tumor had more upper extremity edema than those who did not recur (p2 = 0.085) at 1 year and (p2 = 0.02) at 2 years. In patients who did not develop local recurrence, those who had received XRT had greater but nonsignificant increases in upper extremity circumferential measures compared with those receiving MRM at any anniversary evaluation. Patients receiving MRM and XRT are likely to have some differences in functional outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Generalized elastophagocytic granuloma

The case of an eighty-three-year-old woman with the sudden onset of a generalized pruritic eruption is reported. The skin lesions resembled disseminated subacute lupus erythematosus on clinical examination, but actinic granuloma or annular elastolytic giant cell granuloma was seen in biopsy specimens of the lesions. Our case was differentiated from generalized granuloma annulare by the distinct zoning of elastolysis and the distribution of giant cells.

Diagnosis and surgical management of endometriomas

Fifty two patients with endometriomas greater than 1 cm were treated by surgical excision either with or without ovarian closure. Diagnosis is reliable when clinical features of the pain, vaginal ultrasound, and laparoscopy, including ovarian mobilization and needling, are considered. Fifty of 52 patients were free of pain after 1 year and 26 (50%) became pregnant within 1 year. A second laparoscopy is justified if pain persists or pregnancy does not occur. Adhesive disease was the most common complication (40%), and persistent or recurrent endometriosis occurred in 15%. Surgery by laparoscopy with drainage and excision of the endometrioma without ovarian sutures may be more effective than excision of the endometrioma and ovarian suture.

Diurnal Changes in Perceptions of Energy and Mood

Data from five separate groups of volunteers show that diurnal variation in perceptions of physical and mental energy (‘vigour’) can be simply measured by the use of visual analogue scales. In all five groups, perceptions of vigour were significantly higher in the morning than at other times of day. In three groups where energy levels were measured six times daily the values achieved between 10.00 h and 12.00 h were significantly higher (P< 0.05) than those recorded on rising or retiring.

Some evidence was also found for the existence of high energy levels in the evening (particularly among the undergraduates) and for an ‘afternoon dip’ in energy in about 20% of subjects. Higher levels of positive affect were also found in the morning and levels recorded between 10.00 h and 12.00 h were significantly greater than those on rising or retiring, (P< 0.01). However, no similar diurnal variation was observed for negative affect. The difference may be due to the fact that positive affect has a distinct ‘biological’ component contributing to perceptions of energy, whilst negative affbct depends more on features in the individual's environment, which show no consistent diurnal pattern.

Fluctuations in perceived energy and mood among patients with chronic fatigue syndrome

Patients currently suffering or recently recovered from chronic fatigue syndrome (CFS) were compared with each other and with a group of well-matched controls in a study of diurnal variation in levels of perceived mental and physical energy and positive and negative affect. Patients who were currently ill showed diurnal variation in patterns of energy, with maximum levels being recorded between 10.00 h and 12.00 h which were significantly higher (P < 0.05) than energy levels recorded on rising or retiring. This pattern was similar to the controls but average energy levels at each time point were lower (P < 0.05) among the ill patients. Recovered patients showed the same pattern, with mean energy levels falling between those of the ill patients and controls. Similar diurnal patterns were found for perceptions of positive, though not negative affect. Correlations between physical and mental energy and between both of these energy variables and positive affect were high (r = 0.75 to 0.85) in both controls and CFS patients. However, correlations with negative affect were low (eg r = -0.10) and non-significant. Total scores on the Hospital Anxiety and Depression Scale (HAD) were significantly higher (P < 0.05) among patients who were still ill than those who had recovered. Scores on the HAD Depression (but not Anxiety) subscale were also significantly higher among those who were still ill (P < 0.01). These findings may be of value in facilitating programmes of cognitive-behavioural modification intended to aid the recovery of patients with CFS.

Fibrous mastocytoma in a patient with generalized cutaneous mastocytosis

A 57-year-old woman with cutaneous mastocytosis of 23 years duration developed a hyperpigmented abdominal plaque composed of confluent indurated papules that enlarged for a period of 1 year to 12 x 8 cm. Biopsy showed dermal infiltration by closely packed spindle-shaped mast cells, fibroblasts, collagen, and scattered lymphocytes, predominantly T-suppressor cells. Electron microscopy showed close contact between mast cells, fibroblasts, and lymphocytes. Piecemeal mast cell degranulation and extrusion of mast cell granules was seen, with rare mast cell granules in fibroblasts, and collagen fibers in peripheral and perinuclear endoplasmic reticulum of mast cells. the term Fibrous mastocytoma is suggested for this tumor-like dermal fibrosis, possibly induced by lymphokines.

Activation of bovine immunodeficiency-like virus expression by bovine herpesvirus type 1

Bovine immunodeficiency-like virus (BIV) is a recently identified lentivirus that infects cattle. The virus has structural and genetic similarities to human HIV. The present study demonstrates that BIV can be activated by bovine herpesvirus type 1 (BHV-1), a pathogen frequently associated with cattle diseases. Activation of BIV expression can be detected as increased BIV reverse transcriptase activity, increased in the number of syncytia induced by BIV, and increased in the steady state level of BIV-specific RNA upon BHV-1 super-infection. Additional transactivation studies using the BIV-LTR (long terminal repeat) were conducted. The BIV-LTR was linked to the chloramphenicol acetyl transferase gene (CAT) and transfected into bovine cell cultures in order to quantitate the levels of BIV-LTR expression. When the transfected cells were infected by BHV-1, there was an increase in CAT expression, indicating transactivation of the BIV-LTR by BHV-1. Most of the transactivation activities were abolished with an LTR construct that has deleted the NF-kappa B-like sequence located in the U3 region of the LTR. In order to further demonstrate that activation of the BIV-LTR involves factors that may bind to the LTR sequences, gel retardation assays were carried out using the BIV-LTR U3 region as probe. Our results showed that BHV-1 infection resulted in an induction of factor(s) that binds to the NF-kappa B-like sequence on the BIV-LTR. This suggests that transactivation of BIV by BHV-1 may be mediated by a bovine NF-kappa B-like protein that binds to the target sequence in the BIV promoter region.

The human prohibitin gene located on chromosome 17q21 is mutated in sporadic breast cancer

A gene called "prohibitin" was isolated as a candidate antiproliferating gene in rat liver cells. We have isolated the human homologue of the rat prohibitin gene and mapped it to chromosome 17q12-21 where a gene responsible for hereditary breast cancer was localized. DNA sequence analysis of 2 exons in this gene in 23 sporadic breast cancers, which showed loss of heterozygosity on the long arm of chromosome 17 or developed in patients 35 years old or younger, identified 4 cases of somatic mutation; 2 of these were missense mutations; 1 showed a 2-base deletion resulting in truncation of the gene product due to a frame shift; the other had a C to T transition in an intron adjacent to an intron-exon boundary. These results suggest that this gene may be a tumor suppressor gene and is associated with tumor development and/or progression of at least some breast cancers.

Identification and characterization of a human herpesvirus 6 gene segment that trans activates the human immunodeficiency virus type 1 promoter

Human herpesvirus 6 (HHV-6) is a lymphotropic herpesvirus, and in vitro, HHV-6 can productively infect many of the same cell types as can human immunodeficiency virus (HIV). Coinfection by both viruses in vitro can lead to both activation of the HIV promoter and acceleration of cytopathic effects. We have previously demonstrated that a large, 22.25-kb cloned HHV-6 fragment, pZVB70, can trans activate HIV promoter expression in vitro. In this study, we show that the pZVB70 fragment can trans activate the HIV promoter in human T-cell lines as well as in the monkey kidney cell line CV-1. The pZVB70 insert was digested with various restriction enzymes, and individual fragments were transfected into cells to test for their ability to trans activate the HIV promoter. By this method, we have identified a 1.8-kb subfragment, B701, that is involved in trans activation. Sequence analyses show that B701 potentially encodes a 143-amino-acid protein. This protein shares no homology with other herpesvirus proteins, such as ICP0 and ICP4, that have been shown to trans activate the HIV promoter. However, it shows weak sequence homology with the gene products encoded by the cytomegalovirus early US22 gene family, suggesting that the putative B701 protein may be an HHV-6 early regulatory protein. The 143-amino-acid coding sequence of B701 was cloned by polymerase chain reaction, and transfection of this construct into cells activated HIV promoter expression. The target site on the HIV promoter for the putative B701 protein is mapped to the NF-kappa B binding site. Our results suggest that the putative B701 protein may function by directly binding to the NF-kappa B site or may involve cellular factors, such as NF-kappa B, either directly or indirectly.

An intrachromosomal insertion causing 5q22 deletion and familial adenomatous polyposis coli in two generations

We report familial adenomatous polyposis coli (FAPC) with epidermoid cysts, osteomata, and areas of congenital hypertrophy of the retinal pigment epithelium (CHRPEs) in a male patient and his maternal aunt, both of whom suffered a mild to moderate degree of mental handicap. Both had an interstitial deletion of the long arm of chromosome 5 (del(5)(q22q23.2)). Two other normal family members had the underlying direct insertion of chromosome 5(dir ins(5)(q31.3q22q23.2)). Molecular genetic and fluorescent hybridisation studies have shown that loci D5S37 and D5S98 are outside the deletion whereas loci detected by probes EF5.44 and YN5.48 are lost. As expected, the molecular analyses indicate loss of one allele at the MCC and APC loci. The APC gene is located within band 5q22. Familial direct insertions should be considered as a cause of recurrent microdeletion syndromes.

Indications for endometrial resection

OBJECTIVE

To demonstrate that endometrial resection may be used to control abnormal uterine bleeding in a wide variety of clinical conditions.

DESIGN/SETTING

Sixty-one patients were referred to a private gynaecological practice with abnormal uterine bleeding between January and December 1990. The clinical conditions associated with abnormal uterine bleeding were fibromyomata, adenomyosis, hormone replacement therapy and anticoagulant therapy. Twenty of the patients were referred for consideration of endometrial resection and twelve for consideration of hysterectomy. The advantages and disadvantages of drug therapy, uterine curettage, endometrial resection and hysterectomy were discussed. Forty-two elected to have endometrial resection, thirteen continued with drug therapy after curettage and six proceeded to hysterectomy.

RESULTS

Thirty-five of 42 patients were satisfied with the results of endometrial resection, and 39 of the 42 patients reduced their use of pads or tampons by more than 50%. Three of the failures proceeded to hysterectomy.

CONCLUSIONS

The majority of patients with abnormal uterine bleeding not controlled by drug therapy may be suitable for endometrial resection. This includes patients with intramural fibromyomata and adenomyosis. The patient needs to accept a small chance of failure, the risk of complications (particularly uterine perforation) and the fact that the risk of death from the procedure, while small, has not been established.

Use of bacterial trpE fusion vectors to express and characterize the bovine immunodeficiency-like virus core protein

The gag coding region from Bovine Immunodeficiency-like Virus (BIV) was cloned into E. coli and expressed as a bacterial fusion protein. Six different clones spanning various regions of the gag open reading frame were generated. The resulting fusion proteins were expressed at high concentrations and readily purified. A panel of bovine immune sera specifically recognized the recombinant Gag proteins, as did immune sera from animals infected or immunized with lentiviruses related to BIV, such as Equine Infectious Anemia Virus (EIAV) and Human Immunodeficiency Virus (HIV). Analysis of the deletion clones, using the bovine immune sera panel, enabled us to identify at least one major epitope which was specifically recognized by all bovine sera examined. The ease of expression, purification, and specificity of these fusion proteins should enable a thorough study of the epidemiology of BIV infection.