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Biomedical subjects

M H Allen

Publications and source records attributed to M H Allen.

At least 37 records · Page 2Linked to original sources
PubMed2000

Association of TNFA gene polymorphism at position -308 with susceptibility to irritant contact dermatitis.

Mechanisms underlying susceptibility to skin irritants are not clearly understood. Cytokines play a key role in inflammation, and functional polymorphisms in cytokine genes may affect responses to irritants. We investigated the relationship between polymorphism in the tumor necrosis factor (TNF) alpha-chain gene and responses to irritants. Volunteers (n=221) tested with sodium dodecyl sulfate (SDS) and benzalkonium chloride (BKC) were divided into responders and nonresponders and high and low irritant-threshold groups. DNA was assayed for the TNF-308 polymorphism by a polymerase chain reaction-restriction fragment length polymorphism method. There was a significant increase in the A allele (P=0.030) and AA genotype (P=0.023) in both the SDS low irritant-threshold group and in SDS responders (A allele P=0.022, AA genotype P=0.048). In the BKC low irritant-threshold group, we found a significant increase in the A allele (P=0.002) and AA genotype (P=0.016). Individuals with a low threshold to both irritants demonstrated a significant increase (P=0.002) in the A allele. This is the first description of a nonatopic genetic marker for irritant susceptibility in normal individuals. Genotyping for the TNF-308 polymorphism may thus contribute to screening of individuals deemed at risk of developing irritant contact dermatitis.

Adolescent↗
PubMed2000

Minimally invasive treatment of twin-to-twin transfusion syndrome.

Selective laser photocoagulation of communicating vessels (SLPCV) is an application of minimally invasive endoscopic fetal surgery (i.e., surgical fetoscopy) performed for severe cases of twin-to-twin transfusion syndrome (TTTS), a complication of monochorionic twin pregnancies. Advances in ultrasound and endoscopy have aided the identification and treatment of this potentially lethal or fatal condition. Surgical fetoscopy, an innovation in the field of surgery and maternal-fetal medicine, benefits patients by reducing the morbidity and mortality associated with TTTS, with minimal risks to the mother.

Amniocentesis↗
PubMed2000

Selective versus non-selective laser photocoagulation of placental vessels in twin-to-twin transfusion syndrome.

OBJECTIVE: We have recently described a surgical technique for the treatment of twin-to-twin transfusion syndrome (TTTS) that allows precise identification of vascular anastomoses (selective laser photocoagulation of communicating vessels, or S-LPCV). The purpose of this study was to compare S-LPCV with the previous non-selective technique (NS-LPCV) that targeted all vessels crossing the dividing membrane. MATERIALS AND METHODS: Patients with TTTS were treated with NS-LPCV from May 1994 to June 1997 and with S-LPCV from July 1997 to December 1999. TTTS was defined as polyhydramnios of > or = 8 cm maximum vertical pocket (MVP) in the recipient twin and oligohydramnios of < or = 2 cm MVP in the donor twin. Outcome was measured as survival per number of pregnancies and per number of fetuses together with limited morbidity data. RESULTS: NS-LPCV was used in 18 patients and 74 were treated with S-LPCV. Three patients interrupted their pregnancies electively after surgery (S-LPCV) and were removed from further analysis. Survival of at least one fetus was higher in S-LPCV (83.1%) than in NS-LPCV (61.1%) (P = 0.04), mostly due to a lower rate of dual intra-uterine fetal demise in S-LPCV (5.6%) than in NS-LPCV (22%) (P = 0.05). There were more hydropic fetuses in the NS-LPCV group (27%) than in the S-LPCV group (5.4%), but this difference did not account for the results. There was no difference in the survival per number of fetuses between the two groups. CONCLUSIONS: S-LPCV represents an important evolution in the surgical treatment of TTTS. The use of this technique by all centers should allow better comparison of fetal survival and morbidity rates. S-LPCV should be the standard technique in trials comparing amniocentesis versus laser for the treatment of severe TTTS.

Arteriovenous Anastomosis↗
PubMed2000

Fetal hydrolaparoscopy and endoscopic cystotomy in complicated cases of lower urinary tract obstruction.

OBJECTIVE: Vesicoamniotic shunting may be difficult or impossible in selected cases of fetal lower obstructive uropathy. The purpose of this article is to describe the performance of fetal hydrolaparoscopy and endoscopic fetal cystotomy in two fetuses with complicated lower obstructive uropathy. STUDY DESIGN: Fetal hydrolaparoscopy-endoscopic fetal cystotomy was performed in a patient with a markedly thickened bladder that could not be entered percutaneously. A peritoneoamniotic (bridge) shunt was also placed. Fetal hydrolaparoscopy-endoscopic fetal cystotomy was performed in a second patient with a collapsed bladder from a previous vesicocentesis, because vesicoinfusion resulted in further ascites. Fetal cystoscopy was performed after endoscopic fetal cystotomy, and posterior urethral valves were ablated with neodymium:yttrium-aluminum-garnet laser energy. A vesicoamniotic shunt was left in place. RESULTS: Adequate bladder drainage was obtained in both cases. The first baby required bilateral nephrotomy and a permanent cystotomy at birth and is scheduled for a bladder expansion procedure at the age of year. The second patient had premature rupture of membranes and fetal death from treatment of this complication 5 days after the original procedure. CONCLUSION: Fetal hydrolaparoscopy-endoscopic fetal cystotomy can be performed in complicated cases of lower obstructive uropathy. The procedure involves the creation of a defect in the bladder dome under direct endoscopic visualization within a spontaneous or intentional hydroperitoneum. Peritoneoamniotic shunting, vesicoamniotic shunting, or ablation of posterior urethral valves may then be performed. Fetal hydrolaparoscopy-endoscopic fetal cystotomy should be reserved only for complicated cases of lower obstructive uropathy in which conventional vesicoamniotic shunting is not safely possible. Further experience with fetal hydrolaparoscopy-endoscopic fetal cystotomy is necessary to establish its risks and benefits.

Adult↗
PubMed2000

Managing the agitated psychotic patient: a reappraisal of the evidence.

Under intense public pressure, regulatory agencies have recently defined circumstances in which medications will be considered a form of restraint, so-called "chemical restraint." This article proposes that the emergency management of the agitated patient be viewed as a brief departure from the usual physician-patient collaboration. Viewed in this way, the goal is simply to terminate the emergency in the manner most likely to be acceptable to patients and conducive to a more typical dialogue. To that end, the author reviews all controlled studies of medication treatment of agitation that have appeared in English since the advent of the neuroleptic medications. Issues of diagnosis, relative efficacy, dosage, route, onset, offset, safety, tolerability, and consumer preference are considered.

Administration, Oral↗
PubMed1999

Medical assessment in the psychiatric emergency service.

This chapter examines the frequency and consequences of medical morbidity in psychiatric presentations and reviews the factors that should influence policy decisions surrounding "medical clearance" in PES settings.

Diagnosis, Differential↗
PubMed1999

Level 1 psychiatric emergency services. The tools of the crisis sector.

Psychiatric emergency services have become an increasingly important element in the mental health system. Many approaches to delivering these services have been described but no unifying constructs have emerged. This article reviews the range of psychiatric emergency settings including their structure and functions, the evidence of their benefits to the system, and the controversies surrounding their use. Categorization by capability is proposed as a means of improving the quality and consistency of assessment and treatment. Regional consolidation is proposed as a means of accomplishing these improvements while containing costs.

Community Mental Health Services↗
PubMed1999

Staging of twin-twin transfusion syndrome.

OBJECTIVE: The purpose of this study was to evaluate the prognostic value of sonographic and clinical parameters to develop a staging classification of twin-twin transfusion syndrome (TTTS). STUDY DESIGN: Severe TTTS was defined as the presence of polyhydramnios (maximum vertical pocket of > or = 8 cm) and oligohydramnios (maximum vertical pocket of < or = 2 cm). Nonvisualization of the bladder in the donor twin (-BDT) and absence of presence of hydrops was also noted. The middle cerebral artery, umbilical artery, ductus venosus, and umbilical vein in both fetuses were assessed with pulsed Doppler. Critically abnormal Doppler studies (CADs) were defined as absent/reverse end-diastolic velocity in the umbilical artery, reverse flow in the ductus venosus, or pulsatile flow in the umbilical vein. TTTS was staged as follows: stage I, BDT still visible; stage II, BDT no longer visible, no CADs; stage III, CADs; stage IV, hydrops; stage V, demise of one or both twins. Laser photocoagulation of communicating vessels (LPCV) or umbilical cord ligation was performed depending on the severity of the condition. The study was approved by the Institutional Review Board of St. Joseph's Hospital in Tampa and by the Fetal Therapy Board at Hutzel Hospital, Detroit, and all patients gave informed consent. RESULTS: A total of 80 of 108 referred patients met criteria for surgery, but only 65 were treated surgically: 48 with LPCV and 17 with umbilical cord ligation. Complete Doppler data were obtainable in 41 of 48 LPCV patients. Survival rates by stage for one or two fetuses were statistically different (chi-squared analysis = 12.9, df = 6, p = 0.044). Neither percent size discordance nor gestational age at diagnosis were predictive of outcome. CONCLUSION: Staging of TTTS using the proposed criteria has prognostic significance. This staging system may allow comparison of outcome data of TTTS with different treatment modalities.

Amniocentesis↗
PubMed1999

Symptomatic overlap of cocaine intoxication and acute schizophrenia at emergency presentation.

Cocaine intoxication and acute abstinence alter brain dopaminergic functioning, resulting in behavioral changes closely mimicking the positive and negative symptoms of schizophrenia. In emergency room settings, recent cocaine abuse can be mistaken for schizophrenia and may cause inappropriate diagnosis and in some instances medical mismanagement. Schizophrenia patients presenting with recent cocaine abuse may also present with significant diagnostic and treatment dilemmas. This study attempts to distinguish between cocaine and schizophrenic psychosis by examining patients who present with both recent cocaine abuse and acute schizophrenia (CA+SZ), cocaine intoxication without schizophrenic illness (CA), and acute schizophrenia with no comorbid substance abuse (SZ) within the first 24 hours after arrival at the Bellevue psychiatric emergency service. Clinical assessment included the Brief Psychiatric Rating Scale, the Schedule for the Assessment of Positive Symptoms, and the Schedule for the Assessment of Negative Symptoms. Both cocaine abusing groups were required to have positive urine toxicology screens for inclusion in the study. Multivariate analysis of variance showed the CA+SZ patients present with a clinical profile that overlaps with CA patients on mood and negative symptom dimensions and overlaps with SZ patients on most positive symptoms. CA+SZ patients differed from both groups, however, by presenting with significantly more hallucinatory experiences than cocaine abusing or schizophrenia patient counterparts. Despite considerable overlap, each group of patients presented with a discernible cross-sectional symptom pattern.

Acute Disease↗
PubMed1999

Acute mania: haloperidol dose and augmentation with lithium or lorazepam.

Antipsychotic dosing for acute mania has not been well studied. Combined treatment with lithium and an antipsychotic is the most common treatment, but additional antimanic efficacy of a lithium-antipsychotic combination beyond that of an antipsychotic alone has not been well demonstrated. Furthermore, the possibility that lithium could affect antipsychotic dose requirement is believed to have never been studied. In this study, 63 acutely psychotic bipolar manic inpatients were randomly assigned to receive double-blind treatment with 1 of 2 haloperidol doses, 25 mg/day or 5 mg/day, for 21 days. In addition to haloperidol, subjects were randomly assigned to receive concomitant treatment with placebo, standard lithium, or lorazepam 4 mg/day. The high haloperidol dose produced greater improvement and more side effects than did the low dose. Lithium added to the low dose produced a markedly greater clinical response than did the low dose alone. Lorazepam did not improve the outcome for the patients receiving low-dose haloperidol. The clinical response produced by high-dose haloperidol was not enhanced by adding either lithium or lorazepam. All treatment effects emerged by the fourth day of treatment and persisted. Used alone, a haloperidol dose of 5 mg/day is too low for most manic patients, but concomitant lithium produces a dose-dependent enhancement of haloperidol response. Lorazepam 4 mg/day was insufficient to produce an advantage when added to low-dose haloperidol.

Adult↗
PubMed1999

Production of specific monoclonal antibodies to Aspergillus species and their use in immunohistochemical identification of aspergillosis.

Two anti-Aspergillus murine monoclonal antibodies (MAbs), designated 164G and 611F, have been produced; both specifically recognize cytoplasmic antigens of A. fumigatus, A. flavus, and A. niger by enzyme-linked immunosorbent assay. The MAbs can identify Aspergillus spp. both in frozen sections by immunofluorescence and in paraffin-embedded clinical specimens by immunofluorescence and immunoperoxidase staining.

Animals↗
PubMed1999

Safety and tolerability of oral loading divalproex sodium in acutely manic bipolar patients.

BACKGROUND: Achieving therapeutic blood levels of a mood stabilizer as quickly as possible is desirable in patients with acute mania. We examined the feasibility and safety of an accelerated oral loading strategy (divalproex, 30 mg/kg/day, on days 1 and 2, followed by 20 mg/kg/day on days 3-10) designed to bring serum valproate concentrations to therapeutic levels (i.e., above 50 microg/mL). METHOD: Fifty-nine patients who met DSM-IV diagnostic criteria for current manic episode and who had a Mania Rating Scale score > or = 14 were randomly assigned on a double-blind basis to receive divalproex oral loading (N = 20); divalproex nonloading (N = 20) at a starting dose of 250 mg t.i.d. on days 1 and 2, followed by standard dose titration for days 3 to 10; or lithium carbonate (N = 19) at a starting dose of 300 mg t.i.d., followed by standard dose titration for days 3 to 10. RESULTS: Eighty-four percent of the divalproex-loading patients, but only 30% of the divalproex-nonloading patients, had valproate serum levels above 50 microg/mL at day 3 of the study. None of the lithium-treated patients had serum lithium levels above 0.8 mEq/L at study day 3. No patient was removed from the study because of an adverse event. There were no significant differences between the groups in the frequencies or types of adverse events. CONCLUSION: Accelerated oral loading with divalproex sodium is a feasible and safe method to bring serum valproate concentrations to effective levels rapidly.

Acute Disease↗
PubMed1998

Ultraviolet B induced suppression of induction of contact sensitivity in human skin is not associated with tumour necrosis factor-alpha-308 or interleukin-10 genetic polymorphisms.

Low doses of ultraviolet B (UVB) can induce localized immunosuppression in skin. This effect may be important in the induction of skin cancers and is thought to be mediated by tumour necrosis factor (TNF) alpha and interleukin (IL) 10 in conjunction with other factors. In humans a transition polymorphism in the TNF-alpha gene may affect TNF-alpha secretion and the promoter region of the IL-10 gene contains a CA repeat polymorphism which may affect gene function. We have therefore investigated the association of these polymorphisms with UVB-induced immunosuppression in humans. Volunteers (n = 42) were irradiated with UVB then sensitized on irradiated skin with diphenylcyclopropanone (DPCP) and subsequently antigen challenged with DPCP. DNA was extracted from blood samples and volunteers genotyped for the TNF-alpha polymorphism by polymerase chain reaction (PCR) and restriction digestion. The CA repeat polymorphism was amplified by PCR and sized by gel electrophoresis. Twenty-four volunteers were susceptible to UVB-induced immunosuppression and 18 were resistant. The association of allele frequencies and phenotype was statistically tested using a chi2-test. For both the TNF-alpha and IL-10 polymorphisms, there was no statistically significant association between allele types and response to UVB. These results indicate that variation in the immune response to UVB in humans is not associated with the TNF-alpha-308 transition or IL-10 CA repeat polymorphisms, although other as yet undetected DNA sequence variants of these genes may be involved.

Alleles↗
PubMed1998

Effect of granulocyte macrophage-colony stimulating factor on Langerhans cells in normal and healthy atopic subjects.

Granulocyte macrophage-colony stimulating factor (GM-CSF) is a multipotent cytokine produced by many cutaneous cell types including keratinocytes. Langerhans cells (LC) represent the major antigen-presenting cells in skin, and in vitro studies demonstrate that GM-CSF is of pivotal importance in LC. Healthy volunteers (n = 3 non-atopic, n = 3 with atopy) received recombinant human GM-CSF (0. 05 microg/mL) by intradermal injection for 3 days to the same site. Diluent was injected in a similar manner as control. Biopsies were taken 24 h after the final injection and examined immunohistochemically for LC and inflammatory cell markers. Compared with control sites, intradermal GM-CSF resulted in shortening of dendritic cell processes and redistribution of LC in the epidermis; numbers of CD1a + cells in the epidermis were significantly decreased (P < 0.005), while those in the dermis were significantly increased (P < 0.05) following intradermal GM-CSF when compared with controls. Double labelling studies on epidermal CD1a + cells indicated de novo expression of intercellular adhesion molecule (ICAM)-1 and increased expression of HLA-DR following GM-CSF (P < 0. 005, P < 0.005, respectively). Additional findings included a marked mixed inflammatory cell infiltrate in the dermis and increased expression of the endothelial cell adhesion molecules E-selectin and ICAM-1. These data indicate that in normal human skin, GM-CSF induces changes in the phenotype and distribution of CD1a + cells consistent with LC functional maturation and exit from the epidermis to the dermis. As these events are central to the initiation of cutaneous inflammation, GM-CSF may potentially play a critical role in the pathogenesis of inflammatory dermatoses.

Adolescent↗
PubMed1998

Reliability of telemedicine in evaluating skin tumors.

OBJECTIVES: To determine the reliability of videoconferencing technology in evaluating skin tumors, the impact of the technology on the clinicians' degree of suspicion that a skin tumor is malignant, and the recommendation to do a biopsy. MATERIALS AND METHODS: Four skin cancer screenings were conducted at rural health care facilities in eastern North Carolina that were connected to East Carolina University School of Medicine. A dermatologist saw the patients in person at the local facility, and the same patient was seen by a dermatologist via a T-1 connection to Greenville, North Carolina. RESULTS: The two physicians were in absolute agreement on 59% of the 107 skin tumors evaluated. There were five lesions identified by the on-site dermatologist as a probable or definite malignancy. The degree of concern about a lesion being malignant and the decision whether to do a biopsy were not significantly different, as shown by kappa analysis. CONCLUSION: The concern about the malignancy of a particular skin lesion and the recommendation whether to do a biopsy were not significantly affected by telemedicine technology.

Adult↗
PubMed1998

Interrater agreement among psychiatrist in psychiatric emergency assessments.

OBJECTIVE: The authors' purpose in this study was to investigate the interrater agreement among psychiatrists in psychiatric emergency service settings. The interrater reliability of many of the key concepts in psychiatric emergency service settings has not been studied. METHOD: Videotapes of 30 psychiatric emergency service patient assessment interviews conducted by psychiatrists were shown to eight experienced psychiatric emergency service psychiatrists. The eight psychiatrists rated each videotape on dimensions such as severity of depression and psychosis and recommended a disposition for each patient. Interrater reliability was then explored. RESULTS: The level of agreement (intraclass correlation coefficient) among the reviewing psychiatrists was higher for psychosis and substance abuse but lower for psychopathology, impulse control problems, danger to self, and disposition. The reviewers' disposition recommendations did not match well with the assessing psychiatrist's actual disposition, but comparisons with actual practice should be considered only suggestive. CONCLUSIONS: Psychiatric emergency service assessments need improvement. This may be accomplished by exploring the underlying structure of psychiatric emergency service concepts, the creation and validation of structured assessment tools, and the creation of practice guidelines.

Adult↗