Individuals with JAK1 variants are affected by syndromic features encompassing autoimmunity, atopy, colitis, and dermatitis

Inborn errors of immunity lead to autoimmunity, inflammation, allergy, infection, and/or malignancy. Disease-causing JAK1 gain-of-function (GoF) mutations are considered exceedingly rare and have been identified in only four families. Here, we use forward and reverse genetics to identify 59 individuals harboring one of four heterozygous JAK1 variants. In vitro and ex vivo analysis of these variants revealed hyperactive baseline and cytokine-induced STAT phosphorylation and interferon-stimulated gene (ISG) levels compared with wild-type JAK1. A systematic review of electronic health records from the BioME Biobank revealed increased likelihood of clinical presentation with autoimmunity, atopy, colitis, and/or dermatitis in JAK1 variant-positive individuals. Finally, treatment of one affected patient with severe atopic dermatitis using the JAK1/JAK2-selective inhibitor, baricitinib, resulted in clinically significant improvement. These findings suggest that individually rare JAK1 GoF variants may underlie an emerging syndrome with more common presentations of autoimmune and inflammatory disease (JAACD syndrome). More broadly, individuals who present with such conditions may benefit from genetic testing for the presence of JAK1 GoF variants.

Transmission prevention behaviors in US households with SARS-CoV-2 cases in 2020

Background

SARS-CoV-2 transmission frequently occurs within households, yet few studies describe which household contacts and household units are most likely to engage in transmission-interrupting behaviors.

Methods

We analyzed a COVID-19 prospective household transmission cohort in North Carolina (April-Oct 2020) to quantify changes in physical distancing behaviors among household contacts over 14 days. We evaluated which household contacts were most likely to ever mask at home and to ever share a bedroom with the index case between Days 7-14.

Results

In the presence of a household COVID-19 infection, 24% of household contacts reported ever masking at home during the week before study entry. Masking in the home between Days 7-14 was reported by 26% of household contacts, and was more likely for participants who observed their household index case wearing a mask. Participants of color and participants in high-density households were more likely to mask at home. After adjusting for race/ethnicity, living density was not as clearly associated with masking. Symptomatic household contacts were more likely to share a bedroom with the index case. Working individuals and those with comorbidities avoided sharing a bedroom with the index case.

Conclusion

In-home masking during household exposure to COVID-19 was infrequent in 2020. In light of ongoing transmission of SARS-CoV-2, these findings underscore a need for health campaigns to increase the feasibility and social desirability of in-home masking among exposed household members. Joint messaging on social responsibility and prevention of breakthrough infections, reinfections, and long COVID-19 may help motivate transmission-interruption behaviors.

Household Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 in the United States: Living Density, Viral Load, and Disproportionate Impact on Communities of Color

BACKGROUND

Households are hot spots for severe acute respiratory syndrome coronavirus 2 transmission.

METHODS

This prospective study enrolled 100 coronavirus disease 2019 (COVID-19) cases and 208 of their household members in North Carolina though October 2020, including 44% who identified as Hispanic or non-White. Households were enrolled a median of 6 days from symptom onset in the index case. Incident secondary cases within the household were detected using quantitative polymerase chain reaction of weekly nasal swabs (days 7, 14, 21) or by seroconversion at day 28.

RESULTS

Excluding 73 household contacts who were PCR-positive at baseline, the secondary attack rate (SAR) among household contacts was 32% (33 of 103; 95% confidence interval [CI], 22%-44%). The majority of cases occurred by day 7, with later cases confirmed as household-acquired by viral sequencing. Infected persons in the same household had similar nasopharyngeal viral loads (intraclass correlation coefficient = 0.45; 95% CI, .23-.62). Households with secondary transmission had index cases with a median viral load that was 1.4 log10 higher than those without transmission (P = .03), as well as higher living density (more than 3 persons occupying fewer than 6 rooms; odds ratio, 3.3; 95% CI, 1.02-10.9). Minority households were more likely to experience high living density and had a higher risk of incident infection than did White households (SAR, 51% vs 19%; P = .01).

CONCLUSIONS

Household crowding in the context of high-inoculum infections may amplify the spread of COVID-19, potentially contributing to disproportionate impact on communities of color.

Seasonality and transmissibility of Plasmodium ovale in Bagamoyo District, Tanzania

Background

Plasmodium ovale is a neglected malarial parasite that can form latent hypnozoites in the human liver. Over the last decade, molecular surveillance studies of non-falciparum malaria in Africa have highlighted that P. ovale is circulating below the radar, including areas where Plasmodium falciparum is in decline. To eliminate malaria where P. ovale is endemic, a better understanding of its epidemiology, asymptomatic carriage, and transmission biology is needed.

Methods

We performed a pilot study on P. ovale transmission as part of an ongoing study of human-to-mosquito transmission of P. falciparum from asymptomatic carriers. To characterize the malaria asymptomatic reservoir, cross-sectional qPCR surveys were conducted in Bagamoyo, Tanzania, over three transmission seasons. Positive individuals were enrolled in transmission studies of P. falciparum using direct skin feeding assays (DFAs) with Anopheles gambiae s.s. (IFAKARA strain) mosquitoes. For a subset of participants who screened positive for P. ovale on the day of DFA, we incubated blood-fed mosquitoes for 14 days to assess sporozoite development.

Results

Molecular surveillance of asymptomatic individuals revealed a P. ovale prevalence of 11% (300/2718), compared to 29% (780/2718) for P. falciparum. Prevalence for P. ovale was highest at the beginning of the long rainy season (15.5%, 128/826) in contrast to P. falciparum, which peaked later in both the long and short rainy seasons. Considering that these early-season P. ovale infections were low-density mono-infections (127/128), we speculate many were due to hypnozoite-induced relapse. Six of eight P. ovale-infected asymptomatic individuals who underwent DFAs successfully transmitted P. ovale parasites to A. gambiae.

Conclusions

Plasmodium ovale is circulating at 4–15% prevalence among asymptomatic individuals in coastal Tanzania, largely invisible to field diagnostics. A different seasonal peak from co-endemic P. falciparum, the capacity to relapse, and efficient transmission to Anopheles vectors likely contribute to its persistence amid control efforts focused on P. falciparum.

Graphical Abstract

Perceived Social Support and Latent Herpesvirus Reactivation: Testing Main and Stress-Buffering Effects in an Ethnically Diverse Sample of Adults

OBJECTIVE

Perceived social support is consistently associated with physical health outcomes, and one potential physiological mechanism underlying this association is immune function. In this study, we tested both the main and stress-buffering effects of perceived social support on cellular immunity measured via latent herpesvirus reactivation.

METHODS

Data were collected from a community-based sample of 1443 ethnically diverse adults between the ages of 25 and 90 years. Participants self-reported measures of perceived social support, stressful life events, daily hassles, and perceived stress, and provided a blood sample to assess antibody titers to the herpes simplex virus type 1 and Epstein-Barr virus (EBV).

RESULTS

In accordance with the main effect hypothesis, results indicated that perceived social support was directly associated with EBV viral capsid antigen antibody titers (β = -0.06, 95% confidence interval = -0.12 to -0.01, p = .029). Perceived social support, however, did not interact with stressful life events, daily hassles, or perceived stress to influence latent herpesvirus reactivation (p values > .05). Neither race/ethnicity nor age moderated any of the interactions between perceived social support and the stress measures on latent herpesvirus reactivation (p values > .10).

CONCLUSIONS

Overall, the current study supports the main effect hypothesis, according to which higher levels of perceived social support were associated with lower levels of herpesvirus antibody titers.

Clinical and Epidemiological Features of Acute Zika Virus Infections in León, Nicaragua

The American Zika virus (ZIKV) epidemic has highlighted the need to gain a better understanding of this emerging virus. The goal of this study was to describe the clinical symptoms, laboratory findings, and risk factors for symptomatic ZIKV infection in an area with ongoing transmission of other arboviral infections. We recruited patients at least 2 years of age seeking care at public health centers in León, Nicaragua, between January 2016 and August 2017, for fever, maculopapular rash, and/or nonsuppurative conjunctivitis with a duration of less than 1 week. A laboratory diagnosis of ZIKV was established using a combination of molecular and serological tests. Clinical and laboratory findings and potential risk factors were compared between participants with and without acute ZIKV infection. Fifty-eight (26%) of the 225 participants included in the analysis were found to have acute ZIKV infection. Pregnancy and reports of previous arboviral infection were associated with a higher risk of ZIKV infection. Rash, conjunctivitis, sore throat, and lower absolute neutrophil counts were associated with acute ZIKV infection. The clinical characteristics and risk factors identified were consistent with those identified by previous studies; however, we found sore throat to be a feature of ZIKV infection. We also found that neutrophil counts were lower in ZIKV-infected subjects. These clinical symptoms and laboratory data may help clinicians suspect ZIKV infection during future outbreaks.

High household transmission of SARS-CoV-2 in the United States: living density, viral load, and disproportionate impact on communities of color

Background

Few prospective studies of SARS-CoV-2 transmission within households have been reported from the United States, where COVID-19 cases are the highest in the world and the pandemic has had disproportionate impact on communities of color.

Methods and Findings

This is a prospective observational study. Between April-October 2020, the UNC CO-HOST study enrolled 102 COVID-positive persons and 213 of their household members across the Piedmont region of North Carolina, including 45% who identified as Hispanic/Latinx or non-white. Households were enrolled a median of 6 days from onset of symptoms in the index case. Secondary cases within the household were detected either by PCR of a nasopharyngeal (NP) swab on study day 1 and weekly nasal swabs (days 7, 14, 21) thereafter, or based on seroconversion by day 28. After excluding household contacts exposed at the same time as the index case, the secondary attack rate (SAR) among susceptible household contacts was 60% (106/176, 95% CI 53%-67%). The majority of secondary cases were already infected at study enrollment (73/106), while 33 were observed during study follow-up. Despite the potential for continuous exposure and sequential transmission over time, 93% (84/90, 95% CI 86%-97%) of PCR-positive secondary cases were detected within 14 days of symptom onset in the index case, while 83% were detected within 10 days. Index cases with high NP viral load (>10^6 viral copies/ul) at enrollment were more likely to transmit virus to household contacts during the study (OR 4.9, 95% CI 1.3-18 p=0.02). Furthermore, NP viral load was correlated within families (ICC=0.44, 95% CI 0.26-0.60), meaning persons in the same household were more likely to have similar viral loads, suggesting an inoculum effect. High household living density was associated with a higher risk of secondary household transmission (OR 5.8, 95% CI 1.3-55) for households with >3 persons occupying <6 rooms (SAR=91%, 95% CI 71-98%). Index cases who self-identified as Hispanic/Latinx or non-white were more likely to experience a high living density and transmit virus to a household member, translating into an SAR in minority households of 70%, versus 52% in white households (p=0.05).

Conclusions

SARS-CoV-2 transmits early and often among household members. Risk for spread and subsequent disease is elevated in high-inoculum households with limited living space. Very high infection rates due to household crowding likely contribute to the increased incidence of SARS-CoV-2 infection and morbidity observed among racial and ethnic minorities in the US. Quarantine for 14 days from symptom onset of the first case in the household is appropriate to prevent onward transmission from the household. Ultimately, primary prevention through equitable distribution of effective vaccines is of paramount importance.

Seroepidemiology of SARS-CoV-2 infections in an urban Nicaraguan population

In a Nicaraguan population-based cohort, SARS-CoV-2 seroprevalence was 34%, with higher prevalence in children compared to adults. Having a seropositive household member was associated with a two-fold probability of individual seropositivity, suggesting a role for household transmission. Co-morbidities and preventive behaviors were not associated with SARS-CoV-2 seroprevalence.

Impaired immune responses in streptozotocin-induced type I diabetes in mice. Involvement of high glucose

Diabetes is widely believed to predispose to serious infections. However, the mechanisms linking diabetes and immunosuppression are not well defined. One potential mediator of the altered defence mechanisms is hyperglycaemia. It has been identified as the main factor contributing to the development of diseases associated with diabetes mellitus. In this study we analyse the immune response in diabetes and the direct effect of hyperglycaemia on T and B lymphocyte reactivity. Diabetes induced an early decrease in IgG levels in the secondary response. However, both primary responses against a T-cell-dependent or independent antigen were affected after 6 months of diabetes induction. T- and B- cell proliferation was only decreased at this time. To gain insight into the potential mechanisms involved, we evaluated the influence of hyperglycaemia over the immune response. Pre-incubation of lymph node and spleen cells in a high glucose (HG) containing medium led to a significant time- and dose-dependent decrease in T- and B-cell proliferation. This effect was associated with the presence of HG-derived supernatants. Still viable cells after HG exposition were able to improve their proliferative response when cultured with the mitogen in a fresh standard medium. HG diminished cell viability, increased apoptosis and induced oxidative stress in lymphocytes. These results indicate that HG concentrations can directly affect lymphoid cell growth. An increase in oxidative stress would be implicated in this deleterious effect. The possibility that prolonged exposure to pathologically HG concentrations would result in the immunosuppressive state observed in diabetes is also discussed.

Shell model for rotating turbulence

A modified shell model for rotating turbulence is proposed. The effect of rotation is introduced by a randomized linear term. Randomization is shown to be important in correctly modeling the rotation effect. Numerical simulation shows that the exponent of the energy spectrum in the inertial range changes from -5/3 to -2 as rotation rate increases. The mechanism behind this change is explained by weak turbulence theory and supported by numerical results.

Loss of a single N-linked glycan allows CD4-independent human immunodeficiency virus type 1 infection by altering the position of the gp120 V1/V2 variable loops

The gp120 envelope glycoprotein of primary human immunodeficiency virus type 1 (HIV-1) promotes virus entry by sequentially binding CD4 and the CCR5 chemokine receptor on the target cell. Previously, we adapted a primary HIV-1 isolate, ADA, to replicate in CD4-negative canine cells expressing human CCR5. The gp120 changes responsible for CD4-independent replication were limited to the V2 loop-V1/V2 stem. Here we show that elimination of a single glycosylation site at asparagine 197 in the V1/V2 stem is sufficient for CD4-independent gp120 binding to CCR5 and for HIV-1 entry into CD4-negative cells expressing CCR5. Deletion of the V1/V2 loops also allowed CD4-independent viral entry and gp120 binding to CCR5. The binding of the wild-type ADA gp120 to CCR5 was less dependent upon CD4 at 4 degrees C than at 37 degrees C. In the absence of the V1/V2 loops, neither removal of the N-linked carbohydrate at asparagine 197 nor lowering of the temperature increased the CD4-independent phenotypes. A CCR5-binding conformation of gp120, achieved by CD4 interaction or by modification of temperature, glycosylation, or variable loops, was preferentially recognized by the monoclonal antibody 48d. These results suggest that the CCR5-binding region of gp120 is occluded by the V1/V2 variable loops, the position of which can be modulated by temperature, CD4 binding, or an N-linked glycan in the V1/V2 stem.

Enoxaparin and abciximab adjunctive pharmacotherapy during percutaneous coronary intervention

Randomized controlled trials of patients with non-ST segment elevation acute coronary syndromes have established the superiority of enoxaparin (versus unfractionated heparin) for reducing adverse ischemic outcomes. Furthermore, adjunctive abciximab therapy during percutaneous coronary intervention (PCI) is associated with improved clinical outcomes. Since algorithms for integrating these pharmacotherapies have not been determined, patients undergoing elective PCI were enrolled into 2 distinct and separate studies conducted by the National Investigators Collaborating on Enoxaparin (NICE) study groups (NICE 1 and NICE 4 studies). Patients in NICE 1 were administered enoxaparin 1.0 mg/kg intravenously (without abciximab) and those enrolled in NICE 4 were administered a reduced dose (0.75 mg/kg) of enoxaparin in combination with standard-dose abciximab intravenously during PCI. Bleeding events and ischemic outcomes assessed in-hospital and at 30-days post-PCI were infrequent with either pharmacologic regimen. In the dose regimens studied, enoxaparin with or without abciximab appears to provide safe and effective anticoagulation during PCI. The combination of reduced-dose enoxaparin and abciximab was associated with a low incidence of adverse outcomes (bleeding or ischemic events). Additional studies may be required to establish the relative safety and efficacy of this new adjunctive pharmacologic strategy when compared with the combination of low-dose, weight-adjusted unfractionated heparin and abciximab.

[Contribution of PET using FDG in the diagnosis of lung cancer--first results]

Positron emission tomography (PET), when used with F-18 fluoro-deoxyglucose (FDG), contributes to the evaluation of patients with lung cancer. This technique of imaging detects active tumor tissue by showing increased radiopharmaceutical uptake by metabolically active cells. Thus, PET assists in the early diagnosis of pulmonary malignancies that appear only as non-specific findings on CT-scan or chest X-ray. In addition, it is helpful in staging lung cancer before and after resection, chemotherapy or radiotherapy, or their combined use. We performed 135 FDG-PET studies between July '97-April '99 and present our preliminary results with examples of the main indications for PET in lung cancer.

Bone marrow transplantation depleted of T cells followed by repletion with incremental doses of donor lymphocytes for relapsing patients with chronic myeloid leukemia: a therapeutic strategy

BACKGROUND

For patients with chronic myeloid leukemia (CML), long-term survival after stem cell transplantation requires adequate control of graft-versus-host disease (GVHD) and disease recurrence. Relapsing patients respond to donor lymphocyte infusion (DLI) but develop life-threatening complications.

METHODS

Patients with CML in first chronic phase received bone marrow (n = 14) or peripheral blood progenitor cell transplants (n = 4) from HLA-identical siblings. GVHD prophylaxis was by ex vivo T-cell depletion with CAMPATH 1G. If disease recurred, donors' mononuclear cells were collected by apheresis, the CD3 samples commencing at 10(6)/kg were aliquoted at half-log increment intervals, cryopreserved, and infused until disease clearance.

RESULTS

Eighteen patients (median age: 32.5 years) received transplants. All engrafted without procedure-related mortality. Fourteen patients relapsed, and 13 entered the DLI program. Two developed extensive GVHD after single schedule infusions ranging from 89x10(6) to 670x10(6) mononuclear cells/kg, and one survives in complete remission (CR). The rest, treated with incremental dose DLI, experienced no acute toxicities. One, who had developed grade III steroid-responsive GVHD, died in CR2 from opportunistic infections. Steroids reversed limited cutaneous GVHD and elevated liver enzymes in five patients. Three others developed pancytopenia, and two restored blood counts only after donor peripheral blood progenitor cell infusions. Molecular CR2 was established in 12/13 patients, occurring in 10/11 (91%) on the incremental program at a median accumulation of 67 (range: 5-166) x10(6) CD3 cells/kg. Sixteen of 18 (89%) survive at median of 854.5 days from bone marrow transplantation, 4 in CR1 and 10 in CR2 at a median disease-free survival (for remission 2) duration of 341 days. The median combined disease-free survival of the 14 patients in CR 1+2 is 660 days, with 99% average performance status.

CONCLUSIONS

Escalating DLI leads to safe new molecular CR in most CML relapse patients. These results raise the possibility of using "safe" transplantation programs of T-cell depletion, that include graded DLI as prevention against disease recurrence.

In vivo assessment of the window of barrier opening after osmotic blood-brain barrier disruption in humans

OBJECT

Osmotic blood-brain barrier (BBB) disruption induced by intraarterial infusion of mannitol is used in conjunction with chemotherapy to treat human brain tumors. The time course to barrier closure, or the so-called therapeutic window, has been examined in animals but little information is available in humans. The authors, therefore assessed the time course to barrier closure after osmotic BBB disruption in humans.

METHODS

Disruption of the BBB was demonstrated using 99mTc-glucoheptonate (TcGH) single-photon emission computerized tomography (SPECT) scanning in 12 patients who were treated monthly with combination chemotherapy in conjunction with BBB disruption. The primary diagnosis was primary central nervous system lymphoma in seven patients and primitive neuroectodermal tumors in five. The TcGH (20 mCi) was injected at 1- to 480-minute intervals after osmotic BBB disruption, and patients underwent SPECT scanning after 4 hours. A total of 38 studies was performed. Good-to-excellent BBB disruption was obtained in 29 procedures and poor-to-moderate disruption was seen in the other nine studies. The TcGH indices correlated with the degree of BBB disruption as measured postprocedure on contrast-enhanced CT scans (r = 0.852). Mean baseline TcGH indices were 1.02+/-0.07. For the group of patients with good-to-excellent disruptions the mean indices at 1 minute postdisruption measured 2.19+/-0.18. After 40 minutes no significant change was noted (mean index 2.13+/-0.2). Then the indices declined more steeply and at 120 minutes after the disruption the index was 1.36+/-0.02. A very slow decline was noted between 120 and 240 minutes after mannitol infusion. At 240 minutes the barrier was still open for all good-to-excellent disruptions (index 1.33+/-0.08) but at 480 minutes the mean indices had returned to the baseline level.

CONCLUSIONS

Results of these in vivo human studies indicate that the time course to closure of the disrupted BBB for low-molecular-weight complexes is longer than previously estimated. The barrier is widely open during the first 40 minutes after osmotic BBB disruption and returns to baseline levels only after 6 to 8 hours following the induction of good or excellent disruption. These findings have important clinical implications for the design of therapeutic protocols.

Prevalence of human parvovirus B19 and TT virus in a group of young haemophiliacs in South Africa

A well recognized hazard of transfusion with blood or blood products is the acquisition of a viral infection. Parvovirus B19 and transfusion transmitted virus (TTV) are two of several non-enveloped viruses that may on rare occasions be present in coagulation factor concentrates. The prevalence of these viruses in the South African Haemophilia population has not previously been studied. Thirty-nine Haemophiliac children were investigated for evidence of parvovirus and TTV infection. 26 boys with Haemophilia A had been treated with cryoprecipitate or intermediate purity factor VIII, and 13 boys with Haemophilia B had received prothrombin complex concentrates. All the plasma products were prepared from South African donors and were virally inactivated by heat or solvent/detergent since 1992. A control group of 32 children who had not been transfused were also studied. IgG antibodies to B19 were present in 29 of the 39 patients (74%), 18/26 (69%) with Haemophilia A and 12 of the 13 (85%) with Haemophilia B. None of the patients was IgM antibody positive but two children were PCR positive for B19 DNA. Of the control children, 47% had IgG antibodies to B19, but none were IgM antibody or B19 DNA positive. TTV viral DNA was found in 10.2% of patients and in 9% of the control group. The results indicate that our locally produced plasma products are not a significant source of TTV transmitted infection but may contribute to infection by B19 parvovirus.

A comparison of six cypovirus isolates by cross-hybridisation of their dsRNA genome segments

Genetic relationships between the genome segments of six cypovirus (CPV) isolates were analysed by RNA cross-hybridisation. These included three type 1 viruses and single isolates of types 2, 5 and 12, which collectively are identical to those previously compared by serology and electrophoresis [Mertens et al. (1989), J Gen Virol 70: 173-185]. Since only genome segment 10 of three cypovirus types and segments 8 and 9 of a single virus strain (of type 1) have currently been sequenced, this initial study provides some additional information on sequence variation/similarity in each of the ten genome segments. The RNA of the type 1 viruses showed high levels of cross-hybridisation. Significant but much lower levels of cross-hybridisation were detected between type 1 and the related type 12 CPV. However, only very low levels of cross-hybridisation were detected between the other pairs of viruses. Apart from evidence of a slightly higher level of sequence similarity between the largest segments, the RNA sequence appeared to vary uniformly across the whole genome. There was no evidence for any type specific RNA sequences restricted to individual genome segment(s). The sequence variation, reflected in the levels of RNA sequence similarity and cross hybridisation, correlates well with serological data, showing large differences between CPV types and supports the continued use of electropherotype as one of the 'species parameters' for the classification of cypoviruses.

Effect of exogenous adenosine and its monophosphate on the contractile response to acetylcholine in the human isolated detrusor muscle strips

1. Adenosine (0.1-1 mM) or its 5'-monophosphate (5'-AMP) induced a concentration-dependent relaxation of tension caused by acetylcholine (0.2 microM) in human urinary bladder detrusor strips. 2. This effect was antagonized concentration dependently by theophylline at an apparent pA2 value of about 5. 3. Maximum relaxation by adenosine or 5'-AMP never exceeded 50% and 80%, respectively, of acetylcholine-induced tension. Relaxation by some beta2-adrenoceptor agonists (0.1-0.2 mM) or norepinephrine was limited to about 50% of maximum. 4. The responses to adenosine and terbutaline were additive, causing full relaxation, and suggesting mobilization of distinct mechanisms underlying muscle relaxation.

A novel BCR-ABL rearrangement in a Philadelphia chromosome-positive chronic myelogenous leukaemia variant with thrombocythaemia

Reverse transcription polymerase chain reaction was used to detect an unusual BCR/ABL transcript in a patient who presented with thrombocythaemia and was Philadelphia chromosome positive but weakly reactive to conventional BCR/ABL fusion probes. Sequencing revealed the presence of a 12 bp insert between BCR exon2 (b2) and ABL exon2 (a2). In such cases the use of conventional BCR/ABL probes may lead to false negative results. This is the first report of this transcript. Clinically the patient has responded well to therapy.

The anatomy of the surgical operating microscope and operating positions

This article explores the current status of magnification and illumination in endodontic surgery. The basic operations of the operating microscope are described in detail and common misconceptions regarding its operation are explained. Finally, the various operating positions used in endodontic microsurgery are described and illustrated.

Endodontic microsurgery and the surgical operating microscope

Many clinicians have benefited from using surgical telescopes and headlamps to enhance the visual access of clinical procedures. Historically, the surgical operating microscope has provided opportunities for the medical community in the development of new treatment strategies. Recently, the operating microscope has been introduced into the endodontic community, and its benefits in surgical endodontics have become widely known. Cases that once seemed impossible can now be treated with a high degree of confidence and clinical success. This article describes the advantages of the surgical operating microscope.

Histamine-evoked acetylcholine release in sensitized tracheal preparation

The contractile response to histamine of tracheal muscle was studied in preparations from BSA-sensitized and non-sensitized guinea-pigs. Sensitization did not enhance the overall response to histamine. However, this response showed evidence of acetylcholine participation. In sensitized preparations, atropine (0.1 microM) caused a significant depression of the dose response to histamine (n = 11, p = 0.028), especially in the range 2-8 microM. Physostigmine (0.1 microM) significantly potentiated the effect of histamine (n = 8, p = 0.003), especially at greater than 4 microM histamine. The response to histamine of non-sensitized preparations was not altered by atropine (n = 11) or physostigmine (n = 8). The following agents did not discriminate between sensitized and non-sensitized preparations: Famotidine, an H2 antagonist; dimaprit, an H2 agonist; thioperamide, an H3 antagonist; alpha-methylhistamine, an H3 agonist; gallamine, an M2 antagonist, suggesting that muscarinic M2 receptor dysfunction alone is not sufficient to cause bronchial hyper-responsiveness. The results show that sensitization causes a change in the components of the contractile response to histamine rather than bronchial hyper-responsiveness to this agent.

Utility of relative cerebral blood volume mapping derived from perfusion magnetic resonance imaging in the routine follow up of brain tumors

It was recently demonstrated that imaging of brain tumors by relative cerebral blood volume (CBV) maps reconstructed from dynamic magnetic resonance (MR) data provide similar diagnostic information compared to positron emission tomography (PET) or 201Tl single-photon emission computerized tomography (201Tl-SPECT) scans. The authors used relative CBV mapping for routine follow-up evaluation of patients with brain tumors and compared its sensitivity to diagnostic MR imaging, 201Tl-SPECT and clinical assessment. Fifty-nine patients were prospectively followed using 191 concomitant studies of dual section relative CBV maps, MR imaging, 201Tl-SPECT, and neurological evaluations. Studies were repeated every 2 to 3 months (median three evaluations/patient). The relative CBV maps were graded as relative CBV 0 to 4, where Grades 3 and 4 are indicative of proliferating tumors (four = rapid leak). There were 44 high-grade and 15 low-grade tumors followed during treatment. During the follow-up period a change in relative CBV grade was observed in 56% of the patients, revealing an increasing grade in 72% of them. The rapid leak phenomenon was detected in 35% of all studies and in 81% of those with a worsening relative CBV grade. Tumor progression was detected earlier by relative CBV maps as follows: earlier than MR imaging in 32% of the studies (earlier by a median of 4.5 months; p < 0.01); earlier than 201Tl-SPECT in 63% (median 4.5 months; p < 0.01), and earlier than clinical assessment in 55% (median 6 months; p < 0.01). In 82% of studies with positive MR imaging but negative 201Tl-SPECT, the lesions were smaller than 1.5 cm. The relative CBV maps clearly delineated the appearance of rapid leak in these lesions. Routine use of relative CBV maps that can be implemented on any high-field MR unit and added to the regular MR evaluation provides useful functional information in patients with brain tumors. When used as an adjunct follow-up evaluation it proved more sensitive than the other modalities for early prediction of tumor growth. It is very sensitive to small regional changes, unlike functional imaging such as PET or SPECT scans. Based on previous experience with 76 regional CBV studies, the authors conclude that regional CBV mapping correlates with active tumor and it may separate enhancing scar and radiation injury from infiltrative tumor. A new effect named the rapid leak phenomenon was also observed; this phenomenon, as identified on the regional CBV maps, correlates with high malignancy.

Use of 201Thallium brain SPECT, image registration, and semi-quantitative analysis in the follow-up of brain tumors

OBJECTIVE

To assess the use of 201Thallium SPECT and of Thallium (Tl) uptake indices in the detection and follow-up of cerebral tumors.

MATERIAL AND METHODS

Two-hundred eighty 201Tl, 135 99mTc-HMPAO scintigraphies and 280 MRI studies were acquired in 135 patients with cerebral tumors. Three types of Tl uptake indices were calculated by establishing the ratio of the lesion activity to an homologous ROI (I1), the contralateral hemisphere (I2), and the contralateral scalp (I3). Intermodal coregistration between Tl-SPECT and MRI when used, was performed using Pietrzyk visual interactive method.

RESULTS

Tl uptake indices showed mean values of 2.0 +/- 0.5 (I1); 1.77 +/- 0.57 (I2) and 1.11 +/- 0.40 (I3) in positive scans, and of 1.05 +/- 0.22 (I1), 0.88 +/- 0.22 (I2) and 0.50 +/- 0.15 (I3) in negative scans, respectively. A linear combination of the two less correlated indices lead to a more powerful discrimination between positive and negative studies. Longitudinal follow-up studies in the same patients showed good concordance between the index values and the course of the disease.

CONCLUSION

The use of Tl uptake indices improves the accuracy of Tl-SPECT in the follow-up of brain tumors.

Malignant syphilis (lues maligna) and concurrent infection with HIV

BACKGROUND

During the past 2 1/2 years we observed six patients who had a reactive serology for syphilis, of which four developed widespread noduloulcerative and two vesiculonecrotic lesions. The purpose was to report the occurrence of lues maligna, a rare form of secondary syphilis, in five patients infected with the human immunodeficiency virus (HIV) and in one patient with risk factors for infection.

METHODS

Tzanck preparations, viral cultures, and skin biopsies were performed to evaluate the etiology of the lesions.

RESULTS

Syphilis serology titers ranged from 1:32 to 1:128 and in one instance was as low as 1:8. Such titers can also be found in patients with the latent form of syphilis. Therefore, confirmation of the clinical diagnosis of lues maligna was dependent on skin biopsies that were compatible with secondary syphilis and negative viral studies that excluded varicella, disseminated varicella-zoster or herpes simplex. Lues maligna takes an aggressive course in HIV-infected patients since four of the patients required hospitalization and the two patients who refused to complete treatment, subsequently developed more severe skin and constitutional symptoms.

CONCLUSIONS

HIV-infected patients are at risk for developing lues maligna. Despite its malignant presentation, lues maligna lesions respond rapidly to treatment with penicillin. Secondary syphilis should be added to the list of diseases known to be more aggressive in HIV-infected patients.

Rapid inversion of angular deflection data for certain axisymmetric refractive index distributions

Certain functions useful for representing axisymmetric refractive-index distributions are shown to have exact solutions for Abel transformation of the resulting angular deflection data.

A procedure for RT-PCR amplification of mRNAs on histological specimens

Detection in combination with localization of low copy gene expression can be difficult to achieve. The use of reverse transcription PCR on tissue sections with a fluorescent marker provides localization of mRNA expression on a cellular level, and when combined with confocal microscopy and image analysis it also allows for an estimate of the relative intensity of fluorescence. A good example of the application of this method is the localization of nerve growth factor (NGF) mRNA expression in the inner ear. NGF through indirect tests appears to be present in this system, yet NGF mRNA could not be localized with in situ hybridization using radiolabeled riboprobes. Using fluorescent in situ RT-PCR, we can easily detect the presence of NGF mRNA and localize it to specific cell types within the maturing inner ear.

Registration and display of multimodal images: applications in the extracranial head and neck region

Image registration is a correlation procedure that allows the matching of images obtained by different imaging modalities, both structural and functional. Once registered, they can be combined in a single "fused" image. This technique can be used to improve the interpretation and the quantification of relatively low resolution images obtained in nuclear medicine or to achieve a better diagnosis and treatment planning when high resolution anatomical images are registered. Matching images obtained by different imaging modalities is a major challenge and the various registration techniques are briefly described. The extracranial head and neck region is a challenging field for image registration. A preliminary retrospective experience is presented emphasizing the technique feasibility in a routine clinical context. 2-D and 3-D approaches were used. The requirements for transferring registration technology from the image processing laboratory to clinical practice are discussed, and the contribution of this method to medical interdisciplinary communication is emphasized.

Impact of elderly mother's death on middle age daughters

Daughters' responses to an elderly mother's death are found to be multidimensional. In the first six months of bereavement many daughters experience themes of both holding on and letting go. Measured were depression, grief, somatic reactions, as well as impact on the sense of self, degree of acceptance of the death, and ways in which the tie with the mother endures. Though many of these reactions are intercorrelated, they are differentially associated with characteristics of the daughter, mother, and the quality of their relationship. Relatively sudden deaths were associated with more intense grief, less acceptance, and more thoughts of reunion than deaths that occurred in a nursing home.

Maternofetal transmission of human immunodeficiency virus-1: the role of antibodies to the V3 primary neutralizing domain

The increase in the number of human immunodeficiency virus-1 (HIV-1)-infected children is a direct consequence of the heterosexual spread of the disease to women and the growing number of HIV-positive i.v. drug users. It is not known how the majority of infants born to HIV-1-infected women escape HIV-1 infection, and, for those infected, the timing of HIV-1 transmission has yet to be determined. In addition, the role of maternal antibodies in the prevention of HIV-1 transmission to the fetus is unclear. We have previously demonstrated a correlation between vertical transmission and the absence of high-affinity/avidity antibodies to a peptide, KRI-HIGPGRAFYT, which corresponds to a region of the primary neutralizing domain of the gp120 V3 loop of HIVMN (MN-PND). The present study examines the correlation between the presence of these high affinity antibodies in women completing a pregnancy or undergoing an elective abortion and the detection of HIV-1 infection in their aborted fetuses. In several instances, transmission occurred despite high-affinity antibodies to the MN-PND. We have, therefore, evaluated the reactivity of sera to different MN-PND variants. In one infant born to a mother with high-affinity/avidity antibodies to KRI-HIGPGRAFYT (classic MN-PND), the infected baby developed antibodies to an MN-PND variant peptide against which his mother did not mount a humoral immune response during pregnancy. This finding indicates that fetal infection with MN-PND escape mutants arising during pregnancy may occur during a period when the mother is serologically negative.

Robust and inexpensive equipment design for polymerase chain reaction detection of sequence mutations. Cystic fibrosis in a mother and 2 children analysed

Every polymerase chain reaction (PCR) requires use of a temperature cycler for about 3 hours. Since there are many diagnostic tests using this technology, it is important that robust but inexpensive machinery is available. Such a stand-alone machine has been designed and used to analyse an interesting family in which a mother and her 2 children were diagnosed as having cystic fibrosis.

Lack of agonistic activity in McN-A343 may be circumstantial

1. In Tyrode (Ca++ 1.80 mM) or Krebs (Ca++ 3.36 mM) solution, McN-A343 evoked a dose-dependent contractile response in the naive guinea-pig ileum in the dose range 0.40-40 microM, or bladder in the dose range 0.8-200 microM. 2. After two full cycles of carbachol or bethanechol administration in Tyrode solution, neither preparation responded to McN-A343 for 45 to 60 min. The response in Krebs solution, however, was almost unaltered at 15-30 min. The rate of recovery of the contractile response appears to depend on the calcium content of the medium used. 3. A previous report that McN-A343 failed to evoke a contractile response in the guinea-pig ileum or bladder must be reconsidered in the light of the present findings.