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M T Green

Publications and source records attributed to M T Green.

At least 19 recordsLinked to original sources
PubMed2002

Robust and sensitive nylon hybridization membrane suitable for high-throughput robotic arraying applications.

An important aspect of automated macroarraying is the suitability of the nylon membrane selected on which samples are to be arrayed. PerForma is a positively charged nylon membrane that has been developed specificallyfor automated macroarraying. Tests usingfluorescent hybridization detection methods have shown that immobilized DNA amounts as low as 0.25 pg can be detected and that positive signals are obtainable after 21 stripping cycles. This report describes the improved colony growth, improved handling characteristics, increased hybridization detection sensitivity, and increased stripping and reprobing capability obtained using PerForma.

Cells, Cultured↗
PubMed2001

Chemistry of coordinated nitroxyl. Reagent-specific protonations of trans-Re(CO)(2)(NO)(PR(3))(2) (R = Ph, Cy) that give the neutral nitroxyl complexes cis,trans-ReCl(CO)(2)(NH=O)(PR(3))(2) or the cationic hydride complex [trans,trans-ReH(CO)(2)(NO)(PPh(3))(2)(+)][SO(3)CF(3)(-)].

The reactions of hydrochloric and triflic acids with the five-coordinate nitrosyl complexes trans-Re(CO)(2)(NO)(PR(3))(2) (2a, R = Ph; 2b, R = Cy) have been investigated. Reaction of anhydrous HCl with 2 results in a formal protonation of the nitrosyl ligand and addition of chloride to the metal, giving the neutral nitroxyl complex cis,trans-ReCl(CO)(2)(NH=O)(PR(3))(2) (3a, R = Ph; 3b, R = Cy). Reaction of Brønsted bases with 3a or 3b results in clean conversion of 3 to 2 when the base is appropriately strong (pK(b) approximately 7). Addition of HOSO(2)CF(3) to solutions of 2a results in protonation at the metal and formation of the cationic rhenium hydride [trans,trans-ReH(CO)(2)(NO)(PPh(3))(2)(+)][SO(3)CF(3)(-)] (4) in 74% yield; the deuteride [trans,trans-Re((2)H)(CO)(2)(NO)(PPh(3))(2)(+)][SO(3)CF(3)(-)] (4-d) was analogously prepared from (2)HOSO(2)CF(3). 4 crystallized from CH(2)Cl(2)/Et(2)O solution in the orthorhombic space group Pnma, with a = 17.2201(2) A, b = 23.6119(3) A, c = 9.2380(2) A, and Z = 4. The least-squares refinement converged to R(F) = 0.039 and R(wF(2)()) = 0.063 for the 4330 unique data with I > 2 sigma(I). The structure of 4 shows that the hydride (Re-H = 1.74 A) occupies the position trans to the linear nitrosyl ligand (Re-N-O = 178.1(4) degrees ) in the pseudooctahedral complex cation. Complex 4 does not react with chloride to give 3a. DFT calculations carried out on free nitroxyl and its model complexes [Re(CO)(5)(NH=O)(+)] (5), [mer,trans-Re(CO)(3)(NH=O)(PH(3))(2)(+)] (6), and cis,trans-ReCl(CO)(2)(NH=O)(PH(3))(2) (7) indicate that coordinated nitroxyl acts as both a sigma-donor and pi-acceptor ligand, consistent with the observed trend for nu(NO) in free HN=O (1563 cm(-1)), [mer,trans-Re(CO)(3)(NH=O)(PPh(3))(2)(+)] (1, 1391 cm(-1)), 3a (1376 cm(-1)), and 3b (1335 cm(-1)).

Journal Article↗
PubMed1997

Unilateral keratoconus. Incidence and quantitative topographic analysis.

OBJECTIVE: This study was designed to determine the incidence of unilaterality in a population of patients with clinical keratoconus and to compare quantitative descriptors of topography between affected corneas from patients with unilateral keratoconus and corneas of patients with bilateral disease. DESIGN: Retrospective clinical study with new evaluation of some patients. PARTICIPANTS: One hundred sixty-four patients from the University of Texas South-western Medical Center and Wills Eye Hospital who were diagnosed to have moderate-to-advanced keratoconus on the basis of characteristic topographic patterns associated with corneal thinning. INTERVENTION: Corneal topography was evaluated in both eyes of each patient. MAIN OUTCOME MEASURES: Quantitative descriptors of corneal topography were compared between 5 affected corneas of patients with unilateral keratoconus (combined cases from University of Texas Southwestern, LSU Eye Center, and Wills Eye Hospital) and 15 corneas of patients with moderate-to-advanced bilateral keratoconus (1 cornea from each patient). Indices selected for statistical analysis were the Keratoconus Predication Index (KPI), Surface Asymmetry Index (SAI), and Surface Regularity Index (SRI). RESULTS: Three (1.83%) of 164 patients with moderate-to-advanced keratoconus had no topographic evidence of keratoconus in the opposite eye. There were no statistically significant differences in KPI, SRI, or SAI values between the affected corneas of patients with unilateral and bilateral keratoconus. Over a period of 4 years of observation, signs of keratoconus in the previously normal eye developed in a patient with unilateral keratoconus. CONCLUSIONS: The authors found no differences in the quantitative descriptors of corneal topography between corneas with keratoconus from unilateral and bilateral cases. The authors' results suggest that the incidence of "unilateral" keratoconus is very low. Patients initially diagnosed with unilateral keratoconus, if observed for a sufficient period, commonly had signs of keratoconus develop in the opposite eye. The possibility that all cases of unilateral keratoconus may eventually become bilateral cannot be excluded. Therefore, refractive surgical procedures should not be performed on apparently normal corneas when keratoconus is detected in the opposite eye.

Cornea↗
PubMed1996

Morphological and ultrastructural changes induced in corneal epithelial cells by HIV-1 and HHV-6 in vitro.

PURPOSE: The purpose of this study was to determine whether HIV-1 and HHV-6 are capable of infecting and inducing morphological and ultrastructural changes in corneal epithelial cells in vitro. METHODS: Primary and transformed corneal epithelial cell cultures were infected with HIV-1 or HHV-6 in vitro and analyzed for the presence or absence of viral antigens, DNA sequences, viral particles and inclusions. RESULTS: HIV-1 antigens were detected in 8% of the HIV-1 infected cells and early HHV-6 antigens were present in 12% of the HHV-6 infected cells. The presence of viral DNA sequences in the cultures confirmed these findings. Cells infected with HIV-1 morphologically were not different from uninfected cells, whereas the morphology of HHV-6 infected cells was very similar to cells infected with other human herpesviruses. Cytoplasmic tubuloreticular inclusions were detectable in corneal epithelia cells infected with HIV-1 and intact viral particles were visible only in PBMC used to recover HIV-1 from these cultures. Viral inclusions were also observed in corneal epithelial cells infected with HHV-6. CONCLUSION: These data indicate that HIV-1 and HHV-6 are capable of infecting corneal epithelial cells in vitro, but the viruses are not entering these cells via CD4 or galC receptors. This basic information is important in determining the pathogenic mechanism(s) involved in the development of AIDS-associated corneal disorders.

Antigens, Viral↗
PubMed1995

HIV-1 and HHV-6 antigens and transcripts in retinas of patients with AIDS in the absence of human cytomegalovirus.

PURPOSE: The purpose of this study was to define the agents involved in the development of acquired immune deficiency syndrome (AIDS)-associated retinitis. To achieve this goal, the authors determined the frequency and proximity of the simultaneous presence of human immunodeficiency virus (HIV)-1, human herpesvirus (HHV)-6, and human cytomegalovirus (HCMV) in retinas of patients with AIDS with and without AIDS-associated retinitis. METHODS: Retinal sections from 50 globes from patients with AIDS were analyzed for the presence of viral antigens and transcripts. Group 1 contained 13 globes from patients with HCMV infection. Group 2 contained 20 globes from patients with retinal lesions of uncertain etiology in which HCMV antigen and transcripts were not detected. Group 3 contained 17 globes from patients with no retinal lesions. RESULTS: Retinal sections from all 13 globes (group 1) were positive for HCMV antigens and HIV-1 antigens and transcripts. Six of the 13 retinas were also positive for HHV-6 antigens and transcripts. Sections from 13 of the 20 globes (group 2) were positive for HIV-1 antigens and transcripts, and 5 of these 13 were also positive for HHV-6 antigens and transcripts. Multiple areas in sections from two of the HIV-1-positive retinas showed coinfection with HHV-6. All 17 globes (group 3) were positive for HIV-1 antigens and transcripts. Ten of these 17 retinas were also positive for HHV-6 antigens. Human cytomegalovirus antigens were not detectable in retinas from groups 2 and 3. No viral antigens or transcripts were detectable in retinal sections from 10 HIV-1 negative donors. CONCLUSION: The coexistence of HIV-1 and HHV-6 activity in more than 50% of retinas without HCMV infection suggests that HIV-1 and HHV-6 alone or in combination may predispose retinal tissue to other opportunistic agents such as HCMV during the development of AIDS-associated retinitis.

AIDS-Related Opportunistic Infections↗
PubMed1992

Frequency of dual infections of corneas with HIV-1 and HHV-6.

In the current study, 35 pairs of corneas from asymptomatic carriers of HIV-1 and ten pairs from AIDS patients were analyzed for the presence of HIV-1 and HHV-6. The tissues were evaluated for viral antigens, transcripts, DNA sequences and intact and infectious virus. Three corneas from two asymptomatic carriers of HIV-1 and three corneas from two AIDS patients were culture positive for HIV-1. One of the three HIV-1 positive corneas from an asymptomatic HIV-1 carrier also was culture positive for HHV-6. Two of the tissue culture positive corneas from asymptomatic HIV-1 carriers and two from AIDS patients also tested positive for HIV-1 transcriptional activity by in situ hybridization. The label denoting the transcriptional activity was limited to stromal keratocytes. Most significantly, we were able to demonstrate the presence of HIV-1 particle(s) in sections and cultured PBMC from one of the HIV-1 culture positive corneas. PBMC from the same cornea also contained herpes virus particles. This report strengthens our earlier findings that HIV-1 and HHV-6 can invade corneal tissue, which emphasizes the importance of vigorous screening of corneal donors, specifically donors with HIV-1 exposure.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Transcriptional activity of HIV-1 and HHV-6 in retinal lesions from AIDS patients.

This study determined the frequency of multiple viral (HIV-1, HHV-6, and CMV) infections in 26 retinas from 16 AIDS patients. Of the 12 retinas of 26 that tested positive for HIV-1 DNA sequences, seven also were positive for HHV-6 DNA sequences. Four of these seven retinas were culture positive for HIV-1 and two of the four contained CMV DNA sequences and antigens. Using RNA probes, HIV-1 and HHV-6 transcriptional activity was demonstrated in two of the four HIV-1 culture positive retinas. These retinas also contained CMV DNA sequences and antigens. The results demonstrate that more than 35% of AIDS patients suffer from at least two simultaneous viral infections and 15% suffer from three viral infections. The presence of transcriptional activity of HIV-1 and HHV-6 suggests an active infection.

Acquired Immunodeficiency Syndrome↗
PubMed1991

The incidence of HIV-1 and HHV-6 in corneal buttons.

Twenty pairs of corneas from asymptomatic carriers of HIV-1 and seven pairs from AIDS patients were analyzed for the presence of HIV-1 and HHV-6 antigens, viral transcripts, DNA sequences, and intact and infectious particles. Although serum from all donors was positive for both HIV-1 and HHV-6 antibody by Western blot analysis, only one cornea from an asymptomatic carrier of HIV-1 was positive for HIV-1 and HHV-6. The cornea was positive when tested by tissue culture, PCR, in situ hybridization, and electron microscopy. There was no tear film contamination. These results suggest that HIV-1 and HHV-6 may be capable of invading corneal tissue.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Corneal compression sutures for the reduction of astigmatism after penetrating keratoplasty.

We placed interrupted 9-0 nylon sutures across the graft-host interface of ten eyes with more than 5 diopters of keratometric cylinder after penetrating keratoplasty in order to steepen the flattest corneal meridian and reduce the amount of corneal cylinder. Placement of compression sutures reduced corneal cylinder by an average of almost 6 diopters one week later. Average corneal cylinder was 5.1 diopters nine to 12 months after surgery. Best-corrected visual acuity with spectacles improved by an average of two Snellen lines (20/60 to 20/40) and uncorrected visual acuity improved by an average of one line (20/300 to 20/200). There were no complications related to placement of the sutures. This procedure provides a rapid and simple method for reducing astigmatism after penetrating keratoplasty.

Astigmatism↗
PubMed1989

Demonstration of HIV-1 and HHV-6 in AIDS-associated retinitis.

Using an immunohistochemical technique and monoclonal antisera, HIV-1 and CMV antigens were demonstrated in lesioned areas of retinal tissues from selected AIDS patients. Polymerase chain reaction (PCR) was utilized to detect HIV-1 and HHV-6 DNA sequences in total retinal tissues from these patients. In this study of six eyes from four patients, two of the retinas contained three different viruses, HIV-1, HHV-6 and CMV. To determine whether HIV-1 and HHV-6 DNA sequences were restricted to the intraretinal lesions, normal and lesioned areas were dissected from the retina, DNA was extracted and subjected to amplification using PCR. The results showed that HIV-1 and HHV-6 DNA were restricted to the lesioned areas. All four lesions (from two different patients) utilized in this study showed the presence of CMV antigens immunohistochemically. The combination of viruses present in each lesion was either HIV-1 and CMV or HHV-6 and CMV. Two of four lesions contained HIV-1 and CMV; a third lesion showed the presence of HHV-6 and CMV. The fourth lesion contained only CMV antigens.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Effect of immunization and immunosuppression on induced ocular shedding and recovery of herpes simplex virus in infected rabbits.

Immunization and immunosuppression were evaluated during latent ocular herpes simplex virus, type 1 (HSV-1) infection in the rabbit, using the following parameters: (1) ability to recover virus from preocular tearfilm cultures; (2) reactivation of latent infection by direct electrical stimulation; and (3) recovery of virus from latently infected ganglia by whole-cell co-cultivation. Immunization prior to ocular inoculation of virus significantly reduced both the titer of virus shed into the tearfilm and the duration of virus shedding during primary ocular infection. Half of the non-immunized control rabbits died secondary to virus encephalitis, whereas none of the immunized rabbits died. The immunized rabbits could not be induced to shed virus by electrically stimulating the trigeminal ganglion directly. Immunosuppression of latently infected rabbits with high-dose cyclophosphamide (300 mg kg-1) enhanced virus shedding in the tearfilm and increased mortality due to viral encephalitis. Low-dose cyclophosphamide immunosuppression (40 mg kg-1) did not increase mortality because of viral encephalitis. Tearfilm virus shedding secondary to electrical induction in high-dose and low-dose cyclophosphamide animals was higher than that of control, non-immunosuppressed animals.

Animals↗
PubMed1987

Endogenous Clostridium panophthalmitis.

Acute visual loss, pain, and redness in the left eye developed in a 61-year-old diabetic man. Results of ophthalmologic examination showed 4+ conjunctival hyperemia and chemosis, no light perception, and restricted ocular motility. Through a hazy cornea, a gas bubble was visualized filling about 50% of the anterior chamber. A vitreous tap disclosed myriad gram-positive rods with terminal and subterminal spores. Cultures of the vitreous grew Clostridium septicum, a gas-forming organism. Exploratory abdominal laparotomy showed a ruptured diverticulum of the sigmoid colon with acute peritonitis. In spite of intensive antibiotic therapy, the patient died approximately 24 hours after admission. Results of histopathologic examination of the postmortem left eye demonstrated massive necrosis of the intraocular structures with numerous gram-positive rods confined mainly to the retinal pigment epithelium (RPE), detached retina, and vitreous. To the best of the authors' knowledge, this is the second reported case of C. septicum panophthalmitis. Only 69 cases of clostridial infections with ocular involvement have been recorded previously in the literature.

Clostridium Infections↗
PubMed1987

Study of HSV-1 DNA species from trigeminal ganglia of rabbits during acute and latent infections.

Recurrent herpetic keratitis remains a major cause of corneal blindness in developed countries. A fundamental unanswered question regarding herpes simplex virus infection concerns the relationship between the virus and host cell DNA during latency. In the present study DNA was extracted from trigeminal ganglia during both acute and latent infection following ocular inoculation. Extracted, purified DNA was utilized for transfection and for hybridization studies using a 32P-labeled HSV-1 DNA probe. DNA extracted during acute infection was complete, linear and non-integrated. Autoradiographic patterns of DNA isolated during latent infection were suggestive of two separate DNA species.

Animals↗
PubMed1987

Isolation and characterization of HSV-1 DNA from trigeminal ganglion neurons during suppressed infection in vitro.

The current study analyzed the herpes simplex virus type 1 (HSV1) genome during suppressed and reactivated infection in vitro. Utilization of 3H-labeled HSV1 provided a highly specific probe for intracellular localization, isolation, and characterization of the HSV genome after infection of rabbit trigeminal ganglion neurons. Restriction enzyme analysis of viral DNA extracted during both suppressed and reactivated infection matched that of the HSV1 control DNA. Viral DNAs extracted from both cellular and nuclear fractions of host cells exhibited identical patterns. No detectable alterations in terminal fragments were observed, which suggests that the HSV1 genome is both linear and nonintegrated during suppressed infection in this system.

Animals↗
PubMed1987

Localization of 3H-thymidine-labeled HSV-1 in latently infected rabbit trigeminal ganglion cells.

Although current data favor conservation of virus in a nonreplicating form during latency, the actual host cell-virus relationship during this quiescent period remains an enigma. The purpose of this study was to develop a highly specific probe for direct localization of the HSV type 1 (HSV-1) genome in an animal model that closely mimics human disease. Tritium-labeled HSV-1 was inoculated onto trigeminal ganglion (TG) neurons in vitro and onto New Zealand white rabbit corneas in vivo. During acute infection in vivo and after establishment of latency in vivo or suppressed infection in vitro the TG neurons were processed for autoradiography. Silver grains were localized over nuclei of 8-10% of TG neuron cell bodies during suppressed infection in vitro. Acute infection in vivo resulted in the localization of label over 5-10% of neuron cell bodies and satellite cells per section. During latency the label appeared over nuclei of 1-10% of TG bodies per section. This study shows that directly labeled HSV-1 can be found in TG neuron nuclei both in vivo and in vitro. It also suggests that HSV genetic material is lost from certain neurons when latency is established.

Acute Disease↗
PubMed1984

Suppression of HSV-1 infection in trigeminal ganglion cells. An in vitro model of latency.

The goal of this experiment was to develop an in vitro model of HSV-1 infection and to characterize the virologic parameters associated with such an infection. An in vitro model of HSV-1 infection would offer a defined, efficient, and easily controlled system for studying the mechanisms associated with HSV-1 latency and reactivation. Results indicate that: (1) in the presence of 100 micrograms/ml acyclovir, acute infection is suppressed within 3 days; (2) during suppression, infectious virus was recovered only from whole cell trigeminal ganglion explants (no virus recovery from supernate or homogenized samples); immunofluorescent staining was evident with antiserum to VP175, but not with antiserum to HSV-1 and intranuclear inclusions, but no intact virions were observed in neurons by electron microscopy; (3) 72 hr after desuppression of HSV infected trigeminal ganglion cells infectious HSV-1 was recovered from supernate, homogenized, and whole cell cultures. Immunofluorescent staining was observed with antisera to VP175 and HSV-1; intranuclear inclusions as well as intact virus particles were noted in neurons via electron microscopy.

Acyclovir↗